From a67dc377bb5de542c0f213eec9957372fc14c82e Mon Sep 17 00:00:00 2001
From: Daniel Gerhardt <code@dgerhardt.net>
Date: Mon, 24 Jun 2019 12:24:53 +0200
Subject: [PATCH] Adjust imports to conform with style conventions

The following conventions have been applied:
* Import order: static packages -> other packages -> ARSnova packages
  Rule: (imports) CustomImportOrder
* New line between import package groups
  Rule: (imports) CustomImportOrder
* All packages are imported explicitly (no wildcard imports)
  Rule: (imports) AvoidStarImport
* New line between license comment and package line
  Rule: (whitespace) EmptyLineSeparator
---
 .../de/thm/arsnova/cache/CacheBuster.java     |  1 +
 .../de/thm/arsnova/cache/CacheBusterImpl.java |  8 +--
 .../arsnova/cache/ScheduledCacheBuster.java   |  1 +
 .../de/thm/arsnova/cache/package-info.java    |  1 +
 .../java/de/thm/arsnova/config/AppConfig.java | 37 +++++++-------
 .../de/thm/arsnova/config/AppInitializer.java |  6 +--
 .../thm/arsnova/config/PersistenceConfig.java | 18 ++++---
 .../de/thm/arsnova/config/SecurityConfig.java | 29 +++++------
 .../arsnova/config/SecurityInitializer.java   |  1 +
 .../thm/arsnova/config/WebSocketConfig.java   |  3 +-
 .../de/thm/arsnova/config/package-info.java   |  1 +
 .../controller/AbstractController.java        |  1 +
 .../controller/AbstractEntityController.java  | 38 ++++++++------
 .../arsnova/controller/AnswerController.java  |  6 ++-
 .../controller/AuthenticationController.java  | 10 ++--
 .../arsnova/controller/CommentController.java |  6 ++-
 .../controller/ConfigurationController.java   |  8 +--
 .../arsnova/controller/ContentController.java | 10 ++--
 .../ControllerExceptionHandler.java           | 25 +++++-----
 .../controller/ControllerExceptionHelper.java |  6 +--
 .../DefaultControllerExceptionHandler.java    |  6 +--
 .../controller/JsonViewControllerAdvice.java  |  9 ++--
 .../arsnova/controller/MotdController.java    |  6 ++-
 .../controller/PaginationController.java      |  1 +
 .../arsnova/controller/RoomController.java    |  7 +--
 .../arsnova/controller/UserController.java    | 16 +++---
 .../arsnova/controller/WelcomeController.java | 23 +++++----
 .../thm/arsnova/controller/package-info.java  |  1 +
 .../v2/AuthenticationController.java          | 37 +++++++-------
 .../controller/v2/CommentController.java      | 29 +++++------
 .../controller/v2/ContentController.java      | 49 +++++++++---------
 .../controller/v2/CourseController.java       | 25 +++++-----
 .../controller/v2/FeedbackController.java     | 20 ++++----
 .../controller/v2/LegacyController.java       | 10 ++--
 .../arsnova/controller/v2/MotdController.java | 31 ++++++------
 .../arsnova/controller/v2/RoomController.java | 47 ++++++++---------
 .../controller/v2/SocketController.java       | 17 ++++---
 .../controller/v2/StatisticsController.java   | 12 +++--
 .../arsnova/controller/v2/UserController.java | 11 ++--
 .../thm/arsnova/event/AfterCreationEvent.java |  1 +
 .../thm/arsnova/event/AfterDeletionEvent.java |  1 +
 .../arsnova/event/AfterFullUpdateEvent.java   |  1 +
 .../de/thm/arsnova/event/AfterPatchEvent.java |  5 +-
 .../thm/arsnova/event/AfterUpdateEvent.java   |  1 +
 .../de/thm/arsnova/event/ArsnovaEvent.java    |  1 +
 .../arsnova/event/BeforeCreationEvent.java    |  1 +
 .../arsnova/event/BeforeDeletionEvent.java    |  1 +
 .../arsnova/event/BeforeFullUpdateEvent.java  |  1 +
 .../thm/arsnova/event/BeforePatchEvent.java   |  5 +-
 .../thm/arsnova/event/BeforeUpdateEvent.java  |  1 +
 .../thm/arsnova/event/ChangeScoreEvent.java   |  1 +
 .../java/de/thm/arsnova/event/CrudEvent.java  |  4 +-
 .../event/DeleteFeedbackForRoomsEvent.java    |  5 +-
 .../arsnova/event/FlipFlashcardsEvent.java    |  1 +
 .../thm/arsnova/event/NewFeedbackEvent.java   |  1 +
 .../java/de/thm/arsnova/event/RoomEvent.java  |  1 +
 .../thm/arsnova/event/StateChangeEvent.java   |  5 +-
 .../arsnova/event/StateEventDispatcher.java   | 11 ++--
 .../de/thm/arsnova/event/package-info.java    |  1 +
 .../java/de/thm/arsnova/model/Answer.java     |  9 ++--
 .../thm/arsnova/model/AnswerStatistics.java   |  7 +--
 .../java/de/thm/arsnova/model/Attachment.java |  5 +-
 .../java/de/thm/arsnova/model/Authorize.java  |  2 +
 .../de/thm/arsnova/model/ChoiceAnswer.java    |  5 +-
 .../arsnova/model/ChoiceQuestionContent.java  |  7 +--
 .../arsnova/model/ClientAuthentication.java   |  4 +-
 .../java/de/thm/arsnova/model/Comment.java    |  7 +--
 .../java/de/thm/arsnova/model/Content.java    |  9 ++--
 .../java/de/thm/arsnova/model/Entity.java     |  7 +--
 .../java/de/thm/arsnova/model/Feedback.java   |  5 +-
 .../java/de/thm/arsnova/model/FindQuery.java  |  5 +-
 .../java/de/thm/arsnova/model/LogEntry.java   |  5 +-
 .../thm/arsnova/model/LoginCredentials.java   |  4 +-
 .../de/thm/arsnova/model/MigrationState.java  |  5 +-
 src/main/java/de/thm/arsnova/model/Motd.java  |  7 +--
 src/main/java/de/thm/arsnova/model/Room.java  |  7 +--
 .../de/thm/arsnova/model/RoomStatistics.java  |  4 +-
 .../de/thm/arsnova/model/ScoreOptions.java    |  5 +-
 .../thm/arsnova/model/ServiceDescription.java |  2 +
 .../java/de/thm/arsnova/model/Statistics.java |  4 +-
 .../java/de/thm/arsnova/model/TextAnswer.java |  5 +-
 .../de/thm/arsnova/model/UserProfile.java     |  7 +--
 .../model/migration/FromV2Migrator.java       | 24 ++++++---
 .../arsnova/model/migration/ToV2Migrator.java | 30 ++++++++---
 .../arsnova/model/migration/v2/Answer.java    |  4 +-
 .../model/migration/v2/AnswerOption.java      |  5 +-
 .../migration/v2/ClientAuthentication.java    | 11 ++--
 .../arsnova/model/migration/v2/Comment.java   |  4 +-
 .../migration/v2/CommentReadingCount.java     |  4 +-
 .../arsnova/model/migration/v2/Content.java   |  5 +-
 .../arsnova/model/migration/v2/DbUser.java    |  2 +
 .../arsnova/model/migration/v2/Entity.java    |  2 +
 .../arsnova/model/migration/v2/LogEntry.java  |  5 +-
 .../arsnova/model/migration/v2/LoggedIn.java  |  5 +-
 .../thm/arsnova/model/migration/v2/Motd.java  |  5 +-
 .../arsnova/model/migration/v2/MotdList.java  |  4 +-
 .../thm/arsnova/model/migration/v2/Room.java  |  6 ++-
 .../model/migration/v2/RoomFeature.java       |  5 +-
 .../arsnova/model/migration/v2/RoomInfo.java  |  5 +-
 .../model/migration/v2/VisitedRoom.java       |  4 +-
 .../de/thm/arsnova/model/package-info.java    |  1 +
 .../serialization/CouchDbDocumentMixIn.java   |  2 +
 .../serialization/CouchDbDocumentModule.java  |  2 +
 .../serialization/CouchDbDocumentV2MixIn.java |  2 +
 .../CouchDbObjectMapperFactory.java           |  1 +
 .../CouchDbTypeFieldConverter.java            |  2 +
 .../CouchDbTypeFieldV2Converter.java          |  7 +--
 .../FormatAnswerTypeIdResolver.java           |  5 +-
 .../FormatContentTypeIdResolver.java          |  5 +-
 .../thm/arsnova/model/serialization/View.java |  1 +
 .../transport/ImportExportContainer.java      | 13 ++---
 .../model/transport/ScoreStatistics.java      |  4 +-
 .../arsnova/model/transport/package-info.java |  1 +
 .../java/de/thm/arsnova/package-info.java     |  1 +
 .../arsnova/persistence/AnswerRepository.java |  5 +-
 .../persistence/CommentRepository.java        |  4 +-
 .../persistence/ContentRepository.java        |  4 +-
 .../arsnova/persistence/CrudRepository.java   |  1 +
 .../persistence/LogEntryRepository.java       |  5 +-
 .../arsnova/persistence/MotdRepository.java   |  5 +-
 .../arsnova/persistence/RoomRepository.java   |  5 +-
 .../SessionStatisticsRepository.java          |  1 +
 .../persistence/StatisticsRepository.java     |  1 +
 .../arsnova/persistence/UserRepository.java   |  5 +-
 .../couchdb/CouchDbAnswerRepository.java      | 21 ++++----
 .../couchdb/CouchDbAttachmentRepository.java  |  4 +-
 .../couchdb/CouchDbCommentRepository.java     | 11 ++--
 .../couchdb/CouchDbContentRepository.java     | 21 ++++----
 .../couchdb/CouchDbCrudRepository.java        | 17 ++++---
 .../couchdb/CouchDbInitializer.java           | 31 ++++++------
 .../couchdb/CouchDbLogEntryRepository.java    |  7 +--
 .../couchdb/CouchDbMotdRepository.java        |  9 ++--
 .../couchdb/CouchDbRoomRepository.java        | 33 ++++++------
 .../CouchDbSessionStatisticsRepository.java   |  8 +--
 .../couchdb/CouchDbStatisticsRepository.java  |  9 ++--
 .../couchdb/CouchDbUserRepository.java        |  9 ++--
 .../MigrateFromLegacyCondition.java           |  1 +
 .../couchdb/migrations/Migration.java         |  1 +
 .../couchdb/migrations/MigrationExecutor.java | 13 ++---
 .../couchdb/migrations/V2ToV3Migration.java   | 33 ++++++------
 .../support/MangoCouchDbConnector.java        | 15 +++---
 .../support/MangoQueryResultParser.java       |  8 +--
 .../couchdb/support/MangoResponseHandler.java |  4 +-
 .../couchdb/support/PagedMangoResponse.java   |  1 +
 .../ApplicationPermissionEvaluator.java       | 25 +++++-----
 .../security/CasLogoutSuccessHandler.java     | 10 ++--
 .../security/CasUserDetailsService.java       |  9 ++--
 .../security/CustomLdapUserDetailsMapper.java |  9 ++--
 .../security/GuestUserDetailsService.java     |  9 ++--
 .../LoginAuthenticationFailureHandler.java    | 12 ++---
 .../LoginAuthenticationSucessHandler.java     |  4 +-
 .../RegisteredUserDetailsService.java         | 11 ++--
 .../java/de/thm/arsnova/security/User.java    |  7 +--
 .../jwt/JwtAuthenticationProvider.java        |  4 +-
 .../thm/arsnova/security/jwt/JwtService.java  | 17 ++++---
 .../de/thm/arsnova/security/jwt/JwtToken.java |  7 +--
 .../arsnova/security/jwt/JwtTokenFilter.java  | 14 +++---
 .../arsnova/security/pac4j/OAuthToken.java    |  5 +-
 .../pac4j/OauthAuthenticationProvider.java    |  4 +-
 .../security/pac4j/OauthCallbackFilter.java   | 10 ++--
 .../pac4j/OauthUserDetailsService.java        | 11 ++--
 .../de/thm/arsnova/security/package-info.java |  1 +
 .../de/thm/arsnova/service/AnswerService.java |  7 +--
 .../arsnova/service/AnswerServiceImpl.java    | 37 +++++++-------
 .../arsnova/service/AttachmentService.java    |  4 +-
 .../service/AttachmentServiceImpl.java        |  6 ++-
 .../service/CommentFindQueryService.java      |  9 ++--
 .../thm/arsnova/service/CommentService.java   |  7 +--
 .../arsnova/service/CommentServiceImpl.java   | 25 +++++-----
 .../service/ContentFindQueryService.java      |  9 ++--
 .../thm/arsnova/service/ContentService.java   |  5 +-
 .../arsnova/service/ContentServiceImpl.java   | 39 ++++++++-------
 .../service/DefaultEntityServiceImpl.java     | 30 +++++------
 .../de/thm/arsnova/service/EntityService.java |  9 ++--
 .../thm/arsnova/service/FeedbackService.java  |  1 +
 .../arsnova/service/FeedbackServiceImpl.java  | 19 ++++---
 .../service/FeedbackStorageService.java       |  7 +--
 .../service/FeedbackStorageServiceImpl.java   | 17 ++++---
 .../thm/arsnova/service/FindQueryService.java |  5 +-
 .../de/thm/arsnova/service/MotdService.java   |  5 +-
 .../thm/arsnova/service/MotdServiceImpl.java  | 17 ++++---
 .../service/ResponseProviderService.java      |  1 +
 .../service/ResponseProviderServiceImpl.java  |  4 +-
 .../arsnova/service/RoomFindQueryService.java | 11 ++--
 .../de/thm/arsnova/service/RoomService.java   |  9 ++--
 .../thm/arsnova/service/RoomServiceImpl.java  | 47 ++++++++---------
 .../arsnova/service/StatisticsService.java    |  1 +
 .../service/StatisticsServiceImpl.java        |  6 ++-
 .../de/thm/arsnova/service/StatusService.java |  1 +
 .../arsnova/service/StatusServiceImpl.java    |  4 +-
 .../de/thm/arsnova/service/TimerService.java  |  1 +
 .../thm/arsnova/service/TimerServiceImpl.java | 17 ++++---
 .../arsnova/service/UserFindQueryService.java |  9 ++--
 .../de/thm/arsnova/service/UserService.java   | 15 +++---
 .../thm/arsnova/service/UserServiceImpl.java  | 50 +++++++++++--------
 .../de/thm/arsnova/service/package-info.java  |  1 +
 .../score/QuestionBasedScoreCalculator.java   |  1 +
 .../arsnova/service/score/QuestionScore.java  |  1 +
 .../de/thm/arsnova/service/score/Score.java   |  1 +
 .../score/ScoreBasedScoreCalculator.java      |  1 +
 .../service/score/ScoreCalculator.java        |  1 +
 .../service/score/ScoreCalculatorFactory.java |  1 +
 .../score/ScoreCalculatorFactoryImpl.java     | 14 +++---
 .../thm/arsnova/service/score/UserScore.java  |  1 +
 .../service/score/VariantScoreCalculator.java |  4 +-
 .../java/de/thm/arsnova/util/ImageUtils.java  | 19 +++----
 .../arsnova/util/PaginationListDecorator.java |  1 +
 .../java/de/thm/arsnova/web/CacheControl.java |  1 +
 .../web/CacheControlInterceptorHandler.java   |  6 +--
 .../java/de/thm/arsnova/web/CorsFilter.java   |  4 +-
 .../de/thm/arsnova/web/DeprecatedApi.java     |  1 +
 .../web/DeprecatedApiInterceptorHandler.java  |  6 +--
 .../thm/arsnova/web/InternalEntityAspect.java |  4 +-
 .../arsnova/web/MaintenanceModeFilter.java    | 11 ++--
 .../java/de/thm/arsnova/web/Pagination.java   |  1 +
 ...hApiVersionContentNegotiationStrategy.java | 13 ++---
 .../java/de/thm/arsnova/web/RangeAspect.java  | 17 ++++---
 .../web/ResponseInterceptorHandler.java       |  7 +--
 .../web/V2ContentTypeOverrideFilter.java      | 23 +++++----
 .../arsnova/web/exceptions/package-info.java  |  1 +
 .../java/de/thm/arsnova/web/package-info.java |  1 +
 .../websocket/ArsnovaSocketioServer.java      |  1 +
 .../websocket/ArsnovaSocketioServerImpl.java  | 43 ++++++++--------
 .../WebsocketAuthenticationAspect.java        | 11 ++--
 .../AuthChannelInterceptorAdapter.java        |  8 +--
 .../handler/FeedbackCommandHandler.java       | 10 ++--
 .../websocket/handler/FeedbackHandler.java    |  5 +-
 .../arsnova/websocket/message/Content.java    |  1 +
 .../arsnova/websocket/message/Feedback.java   |  1 +
 .../thm/arsnova/websocket/message/Room.java   |  1 +
 .../websocket/message/package-info.java       |  1 +
 .../thm/arsnova/websocket/package-info.java   |  1 +
 .../de/thm/arsnova/config/AppConfigTest.java  |  6 ++-
 .../de/thm/arsnova/config/TestAppConfig.java  | 10 ++--
 .../arsnova/config/TestPersistanceConfig.java | 13 ++++-
 .../arsnova/config/TestSecurityConfig.java    |  4 +-
 .../controller/AbstractControllerTest.java    | 17 ++++---
 .../v2/AuthenticationControllerTest.java      | 16 +++---
 .../controller/v2/CourseControllerTest.java   | 12 +++--
 .../event/StateEventDispatcherTest.java       | 43 ++++++++--------
 .../de/thm/arsnova/model/ContentTest.java     | 11 ++--
 .../java/de/thm/arsnova/model/EntityTest.java | 14 +++---
 .../de/thm/arsnova/model/FeedbackTest.java    |  8 +--
 .../java/de/thm/arsnova/model/TestClient.java |  7 +--
 .../model/migration/FromV2MigratorTest.java   | 25 +++++-----
 .../model/migration/ToV2MigratorTest.java     | 29 +++++------
 .../service/DefaultEntityServiceImplTest.java | 42 ++++++++--------
 .../arsnova/service/FeedbackServiceTest.java  | 32 ++++++------
 .../thm/arsnova/service/StubUserService.java  | 13 ++---
 .../thm/arsnova/service/UserServiceTest.java  | 43 ++++++++--------
 .../QuestionBasedScoreCalculatorTest.java     | 14 +++---
 .../score/ScoreBasedScoreCalculatorTest.java  | 12 +++--
 .../test/context/support/WithMockUser.java    |  7 +--
 .../WithMockUserSecurityContextFactory.java   |  9 ++--
 .../de/thm/arsnova/util/ImageUtilsTest.java   | 21 +++++---
 .../handler/FeedbackCommandHandlerTest.java   | 17 ++++---
 .../handler/FeedbackHandlerTest.java          |  9 ++--
 257 files changed, 1416 insertions(+), 1064 deletions(-)

diff --git a/src/main/java/de/thm/arsnova/cache/CacheBuster.java b/src/main/java/de/thm/arsnova/cache/CacheBuster.java
index 14ba2ec5b..78c814003 100644
--- a/src/main/java/de/thm/arsnova/cache/CacheBuster.java
+++ b/src/main/java/de/thm/arsnova/cache/CacheBuster.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.cache;
 
 /**
diff --git a/src/main/java/de/thm/arsnova/cache/CacheBusterImpl.java b/src/main/java/de/thm/arsnova/cache/CacheBusterImpl.java
index bcd69ae7a..a21e49dc6 100644
--- a/src/main/java/de/thm/arsnova/cache/CacheBusterImpl.java
+++ b/src/main/java/de/thm/arsnova/cache/CacheBusterImpl.java
@@ -15,17 +15,19 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.cache;
 
+import org.springframework.cache.annotation.CacheEvict;
+import org.springframework.context.event.EventListener;
+import org.springframework.stereotype.Component;
+
 import de.thm.arsnova.event.AfterCreationEvent;
 import de.thm.arsnova.event.AfterDeletionEvent;
 import de.thm.arsnova.event.ChangeScoreEvent;
 import de.thm.arsnova.model.Answer;
 import de.thm.arsnova.model.Comment;
 import de.thm.arsnova.model.Room;
-import org.springframework.cache.annotation.CacheEvict;
-import org.springframework.context.event.EventListener;
-import org.springframework.stereotype.Component;
 
 /**
  * This class is used to evict caches based on events. The events carry all necessary information to clear the
diff --git a/src/main/java/de/thm/arsnova/cache/ScheduledCacheBuster.java b/src/main/java/de/thm/arsnova/cache/ScheduledCacheBuster.java
index a1c82ae18..07bc7ba63 100644
--- a/src/main/java/de/thm/arsnova/cache/ScheduledCacheBuster.java
+++ b/src/main/java/de/thm/arsnova/cache/ScheduledCacheBuster.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.cache;
 
 import org.springframework.cache.annotation.CacheEvict;
diff --git a/src/main/java/de/thm/arsnova/cache/package-info.java b/src/main/java/de/thm/arsnova/cache/package-info.java
index af908a396..24a4552da 100644
--- a/src/main/java/de/thm/arsnova/cache/package-info.java
+++ b/src/main/java/de/thm/arsnova/cache/package-info.java
@@ -1,4 +1,5 @@
 /**
  * Classes and interfaces related to caching
  */
+
 package de.thm.arsnova.cache;
diff --git a/src/main/java/de/thm/arsnova/config/AppConfig.java b/src/main/java/de/thm/arsnova/config/AppConfig.java
index 42832de71..74aaf2e1e 100644
--- a/src/main/java/de/thm/arsnova/config/AppConfig.java
+++ b/src/main/java/de/thm/arsnova/config/AppConfig.java
@@ -15,25 +15,16 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.config;
 
 import com.fasterxml.jackson.annotation.JsonInclude;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.SerializationFeature;
-import de.thm.arsnova.connector.client.ConnectorClient;
-import de.thm.arsnova.connector.client.ConnectorClientImpl;
-import de.thm.arsnova.model.migration.FromV2Migrator;
-import de.thm.arsnova.model.migration.ToV2Migrator;
-import de.thm.arsnova.model.serialization.CouchDbDocumentModule;
-import de.thm.arsnova.model.serialization.View;
-import de.thm.arsnova.util.ImageUtils;
-import de.thm.arsnova.web.CacheControlInterceptorHandler;
-import de.thm.arsnova.web.CorsFilter;
-import de.thm.arsnova.web.DeprecatedApiInterceptorHandler;
-import de.thm.arsnova.web.PathApiVersionContentNegotiationStrategy;
-import de.thm.arsnova.web.ResponseInterceptorHandler;
-import de.thm.arsnova.websocket.ArsnovaSocketioServer;
-import de.thm.arsnova.websocket.ArsnovaSocketioServerImpl;
+import java.nio.charset.Charset;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.beans.factory.annotation.Value;
 import org.springframework.beans.factory.config.PropertiesFactoryBean;
@@ -67,10 +58,20 @@ import org.springframework.web.servlet.config.annotation.ViewResolverRegistry;
 import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
 import org.springframework.web.servlet.view.InternalResourceViewResolver;
 
-import java.nio.charset.Charset;
-import java.util.ArrayList;
-import java.util.Arrays;
-import java.util.List;
+import de.thm.arsnova.connector.client.ConnectorClient;
+import de.thm.arsnova.connector.client.ConnectorClientImpl;
+import de.thm.arsnova.model.migration.FromV2Migrator;
+import de.thm.arsnova.model.migration.ToV2Migrator;
+import de.thm.arsnova.model.serialization.CouchDbDocumentModule;
+import de.thm.arsnova.model.serialization.View;
+import de.thm.arsnova.util.ImageUtils;
+import de.thm.arsnova.web.CacheControlInterceptorHandler;
+import de.thm.arsnova.web.CorsFilter;
+import de.thm.arsnova.web.DeprecatedApiInterceptorHandler;
+import de.thm.arsnova.web.PathApiVersionContentNegotiationStrategy;
+import de.thm.arsnova.web.ResponseInterceptorHandler;
+import de.thm.arsnova.websocket.ArsnovaSocketioServer;
+import de.thm.arsnova.websocket.ArsnovaSocketioServerImpl;
 
 /**
  * Loads property file and configures non-security related beans and components.
diff --git a/src/main/java/de/thm/arsnova/config/AppInitializer.java b/src/main/java/de/thm/arsnova/config/AppInitializer.java
index 26aae5722..780b342f0 100644
--- a/src/main/java/de/thm/arsnova/config/AppInitializer.java
+++ b/src/main/java/de/thm/arsnova/config/AppInitializer.java
@@ -15,15 +15,15 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.config;
 
+import javax.servlet.Filter;
+import javax.servlet.ServletRegistration;
 import org.springframework.web.filter.CharacterEncodingFilter;
 import org.springframework.web.filter.DelegatingFilterProxy;
 import org.springframework.web.servlet.support.AbstractAnnotationConfigDispatcherServletInitializer;
 
-import javax.servlet.Filter;
-import javax.servlet.ServletRegistration;
-
 public class AppInitializer extends AbstractAnnotationConfigDispatcherServletInitializer {
 	@Override
 	protected Class<?>[] getRootConfigClasses() {
diff --git a/src/main/java/de/thm/arsnova/config/PersistenceConfig.java b/src/main/java/de/thm/arsnova/config/PersistenceConfig.java
index 681da8237..570e08c8c 100644
--- a/src/main/java/de/thm/arsnova/config/PersistenceConfig.java
+++ b/src/main/java/de/thm/arsnova/config/PersistenceConfig.java
@@ -15,8 +15,18 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.config;
 
+import org.ektorp.impl.StdCouchDbInstance;
+import org.ektorp.spring.HttpClientFactoryBean;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.ComponentScan;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.Primary;
+import org.springframework.context.annotation.Profile;
+
 import de.thm.arsnova.model.serialization.CouchDbObjectMapperFactory;
 import de.thm.arsnova.persistence.AnswerRepository;
 import de.thm.arsnova.persistence.CommentRepository;
@@ -37,14 +47,6 @@ import de.thm.arsnova.persistence.couchdb.CouchDbSessionStatisticsRepository;
 import de.thm.arsnova.persistence.couchdb.CouchDbStatisticsRepository;
 import de.thm.arsnova.persistence.couchdb.CouchDbUserRepository;
 import de.thm.arsnova.persistence.couchdb.support.MangoCouchDbConnector;
-import org.ektorp.impl.StdCouchDbInstance;
-import org.ektorp.spring.HttpClientFactoryBean;
-import org.springframework.beans.factory.annotation.Value;
-import org.springframework.context.annotation.Bean;
-import org.springframework.context.annotation.ComponentScan;
-import org.springframework.context.annotation.Configuration;
-import org.springframework.context.annotation.Primary;
-import org.springframework.context.annotation.Profile;
 
 @ComponentScan({
 		"de.thm.arsnova.persistence.couchdb"
diff --git a/src/main/java/de/thm/arsnova/config/SecurityConfig.java b/src/main/java/de/thm/arsnova/config/SecurityConfig.java
index 41897f22b..3ad86d54f 100644
--- a/src/main/java/de/thm/arsnova/config/SecurityConfig.java
+++ b/src/main/java/de/thm/arsnova/config/SecurityConfig.java
@@ -15,18 +15,13 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.config;
 
-import de.thm.arsnova.security.CasLogoutSuccessHandler;
-import de.thm.arsnova.security.CasUserDetailsService;
-import de.thm.arsnova.security.CustomLdapUserDetailsMapper;
-import de.thm.arsnova.security.LoginAuthenticationFailureHandler;
-import de.thm.arsnova.security.LoginAuthenticationSucessHandler;
-import de.thm.arsnova.security.RegisteredUserDetailsService;
-import de.thm.arsnova.security.jwt.JwtAuthenticationProvider;
-import de.thm.arsnova.security.jwt.JwtTokenFilter;
-import de.thm.arsnova.security.pac4j.OauthAuthenticationProvider;
-import de.thm.arsnova.security.pac4j.OauthCallbackFilter;
+import java.util.ArrayList;
+import java.util.List;
+import javax.annotation.PostConstruct;
+import javax.servlet.ServletContext;
 import org.jasig.cas.client.validation.Cas20ProxyTicketValidator;
 import org.pac4j.core.client.Client;
 import org.pac4j.core.config.Config;
@@ -85,10 +80,16 @@ import org.springframework.security.web.authentication.logout.SecurityContextLog
 import org.springframework.security.web.header.writers.HstsHeaderWriter;
 import org.springframework.security.web.util.matcher.AntPathRequestMatcher;
 
-import javax.annotation.PostConstruct;
-import javax.servlet.ServletContext;
-import java.util.ArrayList;
-import java.util.List;
+import de.thm.arsnova.security.CasLogoutSuccessHandler;
+import de.thm.arsnova.security.CasUserDetailsService;
+import de.thm.arsnova.security.CustomLdapUserDetailsMapper;
+import de.thm.arsnova.security.LoginAuthenticationFailureHandler;
+import de.thm.arsnova.security.LoginAuthenticationSucessHandler;
+import de.thm.arsnova.security.RegisteredUserDetailsService;
+import de.thm.arsnova.security.jwt.JwtAuthenticationProvider;
+import de.thm.arsnova.security.jwt.JwtTokenFilter;
+import de.thm.arsnova.security.pac4j.OauthAuthenticationProvider;
+import de.thm.arsnova.security.pac4j.OauthCallbackFilter;
 
 /**
  * Loads property file and configures components used for authentication.
diff --git a/src/main/java/de/thm/arsnova/config/SecurityInitializer.java b/src/main/java/de/thm/arsnova/config/SecurityInitializer.java
index 77f73e76c..3869e969d 100644
--- a/src/main/java/de/thm/arsnova/config/SecurityInitializer.java
+++ b/src/main/java/de/thm/arsnova/config/SecurityInitializer.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.config;
 
 import org.springframework.security.web.context.AbstractSecurityWebApplicationInitializer;
diff --git a/src/main/java/de/thm/arsnova/config/WebSocketConfig.java b/src/main/java/de/thm/arsnova/config/WebSocketConfig.java
index 7c4f2f86c..10d6a2008 100644
--- a/src/main/java/de/thm/arsnova/config/WebSocketConfig.java
+++ b/src/main/java/de/thm/arsnova/config/WebSocketConfig.java
@@ -1,6 +1,5 @@
 package de.thm.arsnova.config;
 
-import de.thm.arsnova.websocket.handler.AuthChannelInterceptorAdapter;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.beans.factory.annotation.Value;
 import org.springframework.context.annotation.Configuration;
@@ -10,6 +9,8 @@ import org.springframework.web.socket.config.annotation.EnableWebSocketMessageBr
 import org.springframework.web.socket.config.annotation.StompEndpointRegistry;
 import org.springframework.web.socket.config.annotation.WebSocketMessageBrokerConfigurer;
 
+import de.thm.arsnova.websocket.handler.AuthChannelInterceptorAdapter;
+
 @Configuration
 @EnableWebSocketMessageBroker
 public class WebSocketConfig implements WebSocketMessageBrokerConfigurer {
diff --git a/src/main/java/de/thm/arsnova/config/package-info.java b/src/main/java/de/thm/arsnova/config/package-info.java
index 817ab1d11..da30baa77 100644
--- a/src/main/java/de/thm/arsnova/config/package-info.java
+++ b/src/main/java/de/thm/arsnova/config/package-info.java
@@ -1,4 +1,5 @@
 /**
  * Configuration of Spring's and ARSnova's components
  */
+
 package de.thm.arsnova.config;
diff --git a/src/main/java/de/thm/arsnova/controller/AbstractController.java b/src/main/java/de/thm/arsnova/controller/AbstractController.java
index 46ceb22c8..c0478b538 100644
--- a/src/main/java/de/thm/arsnova/controller/AbstractController.java
+++ b/src/main/java/de/thm/arsnova/controller/AbstractController.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.controller;
 
 /**
diff --git a/src/main/java/de/thm/arsnova/controller/AbstractEntityController.java b/src/main/java/de/thm/arsnova/controller/AbstractEntityController.java
index a680bfa51..81383c637 100644
--- a/src/main/java/de/thm/arsnova/controller/AbstractEntityController.java
+++ b/src/main/java/de/thm/arsnova/controller/AbstractEntityController.java
@@ -15,29 +15,39 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.controller;
 
-import de.thm.arsnova.model.Entity;
-import de.thm.arsnova.model.FindQuery;
-import de.thm.arsnova.service.EntityService;
-import de.thm.arsnova.service.FindQueryService;
-import de.thm.arsnova.web.exceptions.NotFoundException;
+import java.io.IOException;
+import java.util.Collection;
+import java.util.Map;
+import java.util.Set;
+import javax.naming.OperationNotSupportedException;
+import javax.servlet.ServletException;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.http.HttpHeaders;
 import org.springframework.http.HttpStatus;
-import org.springframework.web.bind.annotation.*;
+import org.springframework.web.bind.annotation.DeleteMapping;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PatchMapping;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.PutMapping;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.web.bind.annotation.ResponseStatus;
 import org.springframework.web.util.UriComponentsBuilder;
 
-import javax.naming.OperationNotSupportedException;
-import javax.servlet.ServletException;
-import javax.servlet.http.HttpServletRequest;
-import javax.servlet.http.HttpServletResponse;
-import java.io.IOException;
-import java.util.Collection;
-import java.util.Map;
-import java.util.Set;
+import de.thm.arsnova.model.Entity;
+import de.thm.arsnova.model.FindQuery;
+import de.thm.arsnova.service.EntityService;
+import de.thm.arsnova.service.FindQueryService;
+import de.thm.arsnova.web.exceptions.NotFoundException;
 
 /**
  * Base type for Entity controllers which provides basic CRUD operations and supports Entity patching.
diff --git a/src/main/java/de/thm/arsnova/controller/AnswerController.java b/src/main/java/de/thm/arsnova/controller/AnswerController.java
index 2789bba90..b64a9a446 100644
--- a/src/main/java/de/thm/arsnova/controller/AnswerController.java
+++ b/src/main/java/de/thm/arsnova/controller/AnswerController.java
@@ -15,13 +15,15 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.controller;
 
-import de.thm.arsnova.model.Answer;
-import de.thm.arsnova.service.AnswerService;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 
+import de.thm.arsnova.model.Answer;
+import de.thm.arsnova.service.AnswerService;
+
 @RestController
 @RequestMapping(AnswerController.REQUEST_MAPPING)
 public class AnswerController extends AbstractEntityController<Answer> {
diff --git a/src/main/java/de/thm/arsnova/controller/AuthenticationController.java b/src/main/java/de/thm/arsnova/controller/AuthenticationController.java
index e6b8e2d3c..f9bd848ac 100644
--- a/src/main/java/de/thm/arsnova/controller/AuthenticationController.java
+++ b/src/main/java/de/thm/arsnova/controller/AuthenticationController.java
@@ -15,18 +15,20 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.controller;
 
-import de.thm.arsnova.model.ClientAuthentication;
-import de.thm.arsnova.model.LoginCredentials;
-import de.thm.arsnova.model.UserProfile;
-import de.thm.arsnova.service.UserService;
 import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
 import org.springframework.web.bind.annotation.PostMapping;
 import org.springframework.web.bind.annotation.RequestBody;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 
+import de.thm.arsnova.model.ClientAuthentication;
+import de.thm.arsnova.model.LoginCredentials;
+import de.thm.arsnova.model.UserProfile;
+import de.thm.arsnova.service.UserService;
+
 @RestController
 @RequestMapping("/auth")
 public class AuthenticationController {
diff --git a/src/main/java/de/thm/arsnova/controller/CommentController.java b/src/main/java/de/thm/arsnova/controller/CommentController.java
index 270089799..2c0475891 100644
--- a/src/main/java/de/thm/arsnova/controller/CommentController.java
+++ b/src/main/java/de/thm/arsnova/controller/CommentController.java
@@ -15,13 +15,15 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.controller;
 
-import de.thm.arsnova.model.Comment;
-import de.thm.arsnova.service.CommentService;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 
+import de.thm.arsnova.model.Comment;
+import de.thm.arsnova.service.CommentService;
+
 @RestController
 @RequestMapping(CommentController.REQUEST_MAPPING)
 public class CommentController extends AbstractEntityController<Comment> {
diff --git a/src/main/java/de/thm/arsnova/controller/ConfigurationController.java b/src/main/java/de/thm/arsnova/controller/ConfigurationController.java
index 58f135692..ee0125347 100644
--- a/src/main/java/de/thm/arsnova/controller/ConfigurationController.java
+++ b/src/main/java/de/thm/arsnova/controller/ConfigurationController.java
@@ -15,8 +15,12 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.controller;
 
+import java.util.HashMap;
+import java.util.Map;
+import javax.servlet.http.HttpServletRequest;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.beans.factory.annotation.Value;
@@ -25,10 +29,6 @@ import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RequestMethod;
 import org.springframework.web.bind.annotation.ResponseBody;
 
-import javax.servlet.http.HttpServletRequest;
-import java.util.HashMap;
-import java.util.Map;
-
 /**
  * The ConfigurationController provides frontend clients with information necessary to correctly interact with the
  * backend and other frontends as well as settings for ARSnova. The the alternative /arsnova-config route is necessary
diff --git a/src/main/java/de/thm/arsnova/controller/ContentController.java b/src/main/java/de/thm/arsnova/controller/ContentController.java
index 31101a7af..a62a8034c 100644
--- a/src/main/java/de/thm/arsnova/controller/ContentController.java
+++ b/src/main/java/de/thm/arsnova/controller/ContentController.java
@@ -15,17 +15,19 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.controller;
 
-import de.thm.arsnova.model.AnswerStatistics;
-import de.thm.arsnova.model.Content;
-import de.thm.arsnova.service.AnswerService;
-import de.thm.arsnova.service.ContentService;
 import org.springframework.web.bind.annotation.GetMapping;
 import org.springframework.web.bind.annotation.PathVariable;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 
+import de.thm.arsnova.model.AnswerStatistics;
+import de.thm.arsnova.model.Content;
+import de.thm.arsnova.service.AnswerService;
+import de.thm.arsnova.service.ContentService;
+
 @RestController
 @RequestMapping(ContentController.REQUEST_MAPPING)
 public class ContentController extends AbstractEntityController<Content> {
diff --git a/src/main/java/de/thm/arsnova/controller/ControllerExceptionHandler.java b/src/main/java/de/thm/arsnova/controller/ControllerExceptionHandler.java
index 38b1488ab..7c0ff021b 100644
--- a/src/main/java/de/thm/arsnova/controller/ControllerExceptionHandler.java
+++ b/src/main/java/de/thm/arsnova/controller/ControllerExceptionHandler.java
@@ -15,16 +15,13 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.controller;
 
-import de.thm.arsnova.web.exceptions.BadRequestException;
-import de.thm.arsnova.web.exceptions.ForbiddenException;
-import de.thm.arsnova.web.exceptions.NoContentException;
-import de.thm.arsnova.web.exceptions.NotFoundException;
-import de.thm.arsnova.web.exceptions.NotImplementedException;
-import de.thm.arsnova.web.exceptions.PayloadTooLargeException;
-import de.thm.arsnova.web.exceptions.PreconditionFailedException;
-import de.thm.arsnova.web.exceptions.UnauthorizedException;
+import java.util.Map;
+import javax.naming.OperationNotSupportedException;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
 import org.ektorp.DocumentNotFoundException;
 import org.slf4j.event.Level;
 import org.springframework.http.HttpHeaders;
@@ -42,10 +39,14 @@ import org.springframework.web.bind.annotation.ResponseStatus;
 import org.springframework.web.context.request.WebRequest;
 import org.springframework.web.servlet.mvc.method.annotation.ResponseEntityExceptionHandler;
 
-import javax.naming.OperationNotSupportedException;
-import javax.servlet.http.HttpServletRequest;
-import javax.servlet.http.HttpServletResponse;
-import java.util.Map;
+import de.thm.arsnova.web.exceptions.BadRequestException;
+import de.thm.arsnova.web.exceptions.ForbiddenException;
+import de.thm.arsnova.web.exceptions.NoContentException;
+import de.thm.arsnova.web.exceptions.NotFoundException;
+import de.thm.arsnova.web.exceptions.NotImplementedException;
+import de.thm.arsnova.web.exceptions.PayloadTooLargeException;
+import de.thm.arsnova.web.exceptions.PreconditionFailedException;
+import de.thm.arsnova.web.exceptions.UnauthorizedException;
 
 /**
  * Translates exceptions into HTTP status codes.
diff --git a/src/main/java/de/thm/arsnova/controller/ControllerExceptionHelper.java b/src/main/java/de/thm/arsnova/controller/ControllerExceptionHelper.java
index 0c1a705e0..6760458a6 100644
--- a/src/main/java/de/thm/arsnova/controller/ControllerExceptionHelper.java
+++ b/src/main/java/de/thm/arsnova/controller/ControllerExceptionHelper.java
@@ -15,8 +15,11 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.controller;
 
+import java.util.HashMap;
+import java.util.Map;
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -24,9 +27,6 @@ import org.slf4j.event.Level;
 import org.springframework.beans.factory.annotation.Value;
 import org.springframework.stereotype.Component;
 
-import java.util.HashMap;
-import java.util.Map;
-
 @Component
 public class ControllerExceptionHelper {
 	private static final Logger logger = LoggerFactory.getLogger(ControllerExceptionHelper.class);
diff --git a/src/main/java/de/thm/arsnova/controller/DefaultControllerExceptionHandler.java b/src/main/java/de/thm/arsnova/controller/DefaultControllerExceptionHandler.java
index f76456e66..33d4b272c 100644
--- a/src/main/java/de/thm/arsnova/controller/DefaultControllerExceptionHandler.java
+++ b/src/main/java/de/thm/arsnova/controller/DefaultControllerExceptionHandler.java
@@ -15,8 +15,11 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.controller;
 
+import java.util.Map;
+import javax.servlet.http.HttpServletRequest;
 import org.slf4j.event.Level;
 import org.springframework.core.annotation.AnnotationUtils;
 import org.springframework.http.HttpStatus;
@@ -25,9 +28,6 @@ import org.springframework.web.bind.annotation.ExceptionHandler;
 import org.springframework.web.bind.annotation.ResponseBody;
 import org.springframework.web.bind.annotation.ResponseStatus;
 
-import javax.servlet.http.HttpServletRequest;
-import java.util.Map;
-
 @ControllerAdvice
 public class DefaultControllerExceptionHandler {
 	private ControllerExceptionHelper helper;
diff --git a/src/main/java/de/thm/arsnova/controller/JsonViewControllerAdvice.java b/src/main/java/de/thm/arsnova/controller/JsonViewControllerAdvice.java
index 1e0b1c79a..d845f11a8 100644
--- a/src/main/java/de/thm/arsnova/controller/JsonViewControllerAdvice.java
+++ b/src/main/java/de/thm/arsnova/controller/JsonViewControllerAdvice.java
@@ -15,9 +15,12 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.controller;
 
-import de.thm.arsnova.model.serialization.View;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.List;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.core.MethodParameter;
@@ -30,9 +33,7 @@ import org.springframework.web.bind.annotation.ControllerAdvice;
 import org.springframework.web.servlet.mvc.method.annotation.AbstractMappingJacksonResponseBodyAdvice;
 import org.springframework.web.util.UriComponentsBuilder;
 
-import java.util.Collection;
-import java.util.Collections;
-import java.util.List;
+import de.thm.arsnova.model.serialization.View;
 
 /**
  * This {@link ControllerAdvice} applies a {@link View} based on the
diff --git a/src/main/java/de/thm/arsnova/controller/MotdController.java b/src/main/java/de/thm/arsnova/controller/MotdController.java
index c79760227..5359b20a6 100644
--- a/src/main/java/de/thm/arsnova/controller/MotdController.java
+++ b/src/main/java/de/thm/arsnova/controller/MotdController.java
@@ -15,13 +15,15 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.controller;
 
-import de.thm.arsnova.model.Motd;
-import de.thm.arsnova.service.MotdService;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 
+import de.thm.arsnova.model.Motd;
+import de.thm.arsnova.service.MotdService;
+
 @RestController
 @RequestMapping(MotdController.REQUEST_MAPPING)
 public class MotdController extends AbstractEntityController<Motd> {
diff --git a/src/main/java/de/thm/arsnova/controller/PaginationController.java b/src/main/java/de/thm/arsnova/controller/PaginationController.java
index 618bb7e75..3f0983db4 100644
--- a/src/main/java/de/thm/arsnova/controller/PaginationController.java
+++ b/src/main/java/de/thm/arsnova/controller/PaginationController.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.controller;
 
 /**
diff --git a/src/main/java/de/thm/arsnova/controller/RoomController.java b/src/main/java/de/thm/arsnova/controller/RoomController.java
index 1dce11dff..67eb68cba 100644
--- a/src/main/java/de/thm/arsnova/controller/RoomController.java
+++ b/src/main/java/de/thm/arsnova/controller/RoomController.java
@@ -15,10 +15,10 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.controller;
 
-import de.thm.arsnova.model.Room;
-import de.thm.arsnova.service.RoomService;
+import java.util.Set;
 import org.springframework.web.bind.annotation.DeleteMapping;
 import org.springframework.web.bind.annotation.GetMapping;
 import org.springframework.web.bind.annotation.PathVariable;
@@ -27,7 +27,8 @@ import org.springframework.web.bind.annotation.RequestBody;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 
-import java.util.Set;
+import de.thm.arsnova.model.Room;
+import de.thm.arsnova.service.RoomService;
 
 @RestController
 @RequestMapping(RoomController.REQUEST_MAPPING)
diff --git a/src/main/java/de/thm/arsnova/controller/UserController.java b/src/main/java/de/thm/arsnova/controller/UserController.java
index 32597cae8..cd6519a23 100644
--- a/src/main/java/de/thm/arsnova/controller/UserController.java
+++ b/src/main/java/de/thm/arsnova/controller/UserController.java
@@ -15,16 +15,10 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.controller;
 
 import com.fasterxml.jackson.annotation.JsonView;
-import de.thm.arsnova.model.LoginCredentials;
-import de.thm.arsnova.model.UserProfile;
-import de.thm.arsnova.model.serialization.View;
-import de.thm.arsnova.service.RoomService;
-import de.thm.arsnova.service.UserService;
-import de.thm.arsnova.web.exceptions.BadRequestException;
-import de.thm.arsnova.web.exceptions.ForbiddenException;
 import org.springframework.web.bind.annotation.PathVariable;
 import org.springframework.web.bind.annotation.PostMapping;
 import org.springframework.web.bind.annotation.RequestBody;
@@ -33,6 +27,14 @@ import org.springframework.web.bind.annotation.RequestMethod;
 import org.springframework.web.bind.annotation.RequestParam;
 import org.springframework.web.bind.annotation.RestController;
 
+import de.thm.arsnova.model.LoginCredentials;
+import de.thm.arsnova.model.UserProfile;
+import de.thm.arsnova.model.serialization.View;
+import de.thm.arsnova.service.RoomService;
+import de.thm.arsnova.service.UserService;
+import de.thm.arsnova.web.exceptions.BadRequestException;
+import de.thm.arsnova.web.exceptions.ForbiddenException;
+
 @RestController
 @RequestMapping(UserController.REQUEST_MAPPING)
 public class UserController extends AbstractEntityController<UserProfile> {
diff --git a/src/main/java/de/thm/arsnova/controller/WelcomeController.java b/src/main/java/de/thm/arsnova/controller/WelcomeController.java
index 6773eabfe..de5638845 100644
--- a/src/main/java/de/thm/arsnova/controller/WelcomeController.java
+++ b/src/main/java/de/thm/arsnova/controller/WelcomeController.java
@@ -15,10 +15,18 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.controller;
 
-import de.thm.arsnova.web.exceptions.BadRequestException;
-import de.thm.arsnova.web.exceptions.NoContentException;
+import java.net.InetAddress;
+import java.net.MalformedURLException;
+import java.net.URL;
+import java.net.UnknownHostException;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Properties;
+import javax.annotation.Resource;
+import javax.servlet.http.HttpServletRequest;
 import org.springframework.beans.factory.annotation.Value;
 import org.springframework.http.HttpHeaders;
 import org.springframework.http.HttpStatus;
@@ -34,15 +42,8 @@ import org.springframework.web.client.RestTemplate;
 import org.springframework.web.servlet.View;
 import org.springframework.web.servlet.view.RedirectView;
 
-import javax.annotation.Resource;
-import javax.servlet.http.HttpServletRequest;
-import java.net.InetAddress;
-import java.net.MalformedURLException;
-import java.net.URL;
-import java.net.UnknownHostException;
-import java.util.HashMap;
-import java.util.Map;
-import java.util.Properties;
+import de.thm.arsnova.web.exceptions.BadRequestException;
+import de.thm.arsnova.web.exceptions.NoContentException;
 
 /**
  * Default controller that handles requests which have not set a path.
diff --git a/src/main/java/de/thm/arsnova/controller/package-info.java b/src/main/java/de/thm/arsnova/controller/package-info.java
index 71e44bcf6..838e3210f 100644
--- a/src/main/java/de/thm/arsnova/controller/package-info.java
+++ b/src/main/java/de/thm/arsnova/controller/package-info.java
@@ -1,4 +1,5 @@
 /**
  * The 'C' in MVC
  */
+
 package de.thm.arsnova.controller;
diff --git a/src/main/java/de/thm/arsnova/controller/v2/AuthenticationController.java b/src/main/java/de/thm/arsnova/controller/v2/AuthenticationController.java
index e278d0166..706afd616 100644
--- a/src/main/java/de/thm/arsnova/controller/v2/AuthenticationController.java
+++ b/src/main/java/de/thm/arsnova/controller/v2/AuthenticationController.java
@@ -15,16 +15,19 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.controller.v2;
 
-import de.thm.arsnova.config.SecurityConfig;
-import de.thm.arsnova.controller.AbstractController;
-import de.thm.arsnova.model.ServiceDescription;
-import de.thm.arsnova.model.UserProfile;
-import de.thm.arsnova.model.migration.v2.ClientAuthentication;
-import de.thm.arsnova.security.User;
-import de.thm.arsnova.service.UserService;
-import de.thm.arsnova.web.exceptions.UnauthorizedException;
+import java.io.IOException;
+import java.text.MessageFormat;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.List;
+import javax.annotation.PostConstruct;
+import javax.servlet.ServletContext;
+import javax.servlet.ServletException;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
 import org.pac4j.core.context.J2EContext;
 import org.pac4j.core.exception.HttpAction;
 import org.pac4j.oauth.client.FacebookClient;
@@ -54,16 +57,14 @@ import org.springframework.web.bind.annotation.ResponseBody;
 import org.springframework.web.servlet.View;
 import org.springframework.web.servlet.view.RedirectView;
 
-import javax.annotation.PostConstruct;
-import javax.servlet.ServletContext;
-import javax.servlet.ServletException;
-import javax.servlet.http.HttpServletRequest;
-import javax.servlet.http.HttpServletResponse;
-import java.io.IOException;
-import java.text.MessageFormat;
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.List;
+import de.thm.arsnova.config.SecurityConfig;
+import de.thm.arsnova.controller.AbstractController;
+import de.thm.arsnova.model.ServiceDescription;
+import de.thm.arsnova.model.UserProfile;
+import de.thm.arsnova.model.migration.v2.ClientAuthentication;
+import de.thm.arsnova.security.User;
+import de.thm.arsnova.service.UserService;
+import de.thm.arsnova.web.exceptions.UnauthorizedException;
 
 /**
  * Handles authentication specific requests.
diff --git a/src/main/java/de/thm/arsnova/controller/v2/CommentController.java b/src/main/java/de/thm/arsnova/controller/v2/CommentController.java
index ae63d490f..1d0c3318f 100644
--- a/src/main/java/de/thm/arsnova/controller/v2/CommentController.java
+++ b/src/main/java/de/thm/arsnova/controller/v2/CommentController.java
@@ -15,24 +15,17 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.controller.v2;
 
-import de.thm.arsnova.controller.PaginationController;
-import de.thm.arsnova.model.Room;
-import de.thm.arsnova.model.migration.FromV2Migrator;
-import de.thm.arsnova.model.migration.ToV2Migrator;
-import de.thm.arsnova.model.migration.v2.Comment;
-import de.thm.arsnova.model.migration.v2.CommentReadingCount;
-import de.thm.arsnova.service.CommentService;
-import de.thm.arsnova.service.RoomService;
-import de.thm.arsnova.service.UserService;
-import de.thm.arsnova.web.DeprecatedApi;
-import de.thm.arsnova.web.Pagination;
 import io.swagger.annotations.Api;
 import io.swagger.annotations.ApiOperation;
 import io.swagger.annotations.ApiParam;
 import io.swagger.annotations.ApiResponse;
 import io.swagger.annotations.ApiResponses;
+import java.io.IOException;
+import java.util.List;
+import java.util.stream.Collectors;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.MediaType;
@@ -44,9 +37,17 @@ import org.springframework.web.bind.annotation.RequestParam;
 import org.springframework.web.bind.annotation.ResponseStatus;
 import org.springframework.web.bind.annotation.RestController;
 
-import java.io.IOException;
-import java.util.List;
-import java.util.stream.Collectors;
+import de.thm.arsnova.controller.PaginationController;
+import de.thm.arsnova.model.Room;
+import de.thm.arsnova.model.migration.FromV2Migrator;
+import de.thm.arsnova.model.migration.ToV2Migrator;
+import de.thm.arsnova.model.migration.v2.Comment;
+import de.thm.arsnova.model.migration.v2.CommentReadingCount;
+import de.thm.arsnova.service.CommentService;
+import de.thm.arsnova.service.RoomService;
+import de.thm.arsnova.service.UserService;
+import de.thm.arsnova.web.DeprecatedApi;
+import de.thm.arsnova.web.Pagination;
 
 /**
  * Handles requests related to comments.
diff --git a/src/main/java/de/thm/arsnova/controller/v2/ContentController.java b/src/main/java/de/thm/arsnova/controller/v2/ContentController.java
index 8942eea2c..e57ba8cf7 100644
--- a/src/main/java/de/thm/arsnova/controller/v2/ContentController.java
+++ b/src/main/java/de/thm/arsnova/controller/v2/ContentController.java
@@ -15,8 +15,33 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.controller.v2;
 
+import io.swagger.annotations.Api;
+import io.swagger.annotations.ApiOperation;
+import io.swagger.annotations.ApiResponse;
+import io.swagger.annotations.ApiResponses;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
+import java.util.stream.Collectors;
+import java.util.stream.StreamSupport;
+import javax.naming.OperationNotSupportedException;
+import javax.servlet.http.HttpServletResponse;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.MediaType;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RequestMethod;
+import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.web.bind.annotation.ResponseStatus;
+import org.springframework.web.bind.annotation.RestController;
+
 import de.thm.arsnova.controller.PaginationController;
 import de.thm.arsnova.model.ChoiceAnswer;
 import de.thm.arsnova.model.ChoiceQuestionContent;
@@ -37,30 +62,6 @@ import de.thm.arsnova.web.exceptions.ForbiddenException;
 import de.thm.arsnova.web.exceptions.NoContentException;
 import de.thm.arsnova.web.exceptions.NotFoundException;
 import de.thm.arsnova.web.exceptions.NotImplementedException;
-import io.swagger.annotations.Api;
-import io.swagger.annotations.ApiOperation;
-import io.swagger.annotations.ApiResponse;
-import io.swagger.annotations.ApiResponses;
-import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.http.HttpStatus;
-import org.springframework.http.MediaType;
-import org.springframework.web.bind.annotation.PathVariable;
-import org.springframework.web.bind.annotation.RequestBody;
-import org.springframework.web.bind.annotation.RequestMapping;
-import org.springframework.web.bind.annotation.RequestMethod;
-import org.springframework.web.bind.annotation.RequestParam;
-import org.springframework.web.bind.annotation.ResponseStatus;
-import org.springframework.web.bind.annotation.RestController;
-
-import javax.naming.OperationNotSupportedException;
-import javax.servlet.http.HttpServletResponse;
-import java.io.IOException;
-import java.util.ArrayList;
-import java.util.Arrays;
-import java.util.Collections;
-import java.util.List;
-import java.util.stream.Collectors;
-import java.util.stream.StreamSupport;
 
 /**
  * Handles requests related to contents.
diff --git a/src/main/java/de/thm/arsnova/controller/v2/CourseController.java b/src/main/java/de/thm/arsnova/controller/v2/CourseController.java
index 4984cebec..0d22197d8 100644
--- a/src/main/java/de/thm/arsnova/controller/v2/CourseController.java
+++ b/src/main/java/de/thm/arsnova/controller/v2/CourseController.java
@@ -15,8 +15,21 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.controller.v2;
 
+import io.swagger.annotations.ApiParam;
+import java.io.Serializable;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.Comparator;
+import java.util.List;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RequestMethod;
+import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.web.bind.annotation.RestController;
+
 import de.thm.arsnova.connector.client.ConnectorClient;
 import de.thm.arsnova.connector.model.Course;
 import de.thm.arsnova.connector.model.UserRole;
@@ -25,18 +38,6 @@ import de.thm.arsnova.security.User;
 import de.thm.arsnova.service.UserService;
 import de.thm.arsnova.web.exceptions.NotImplementedException;
 import de.thm.arsnova.web.exceptions.UnauthorizedException;
-import io.swagger.annotations.ApiParam;
-import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.web.bind.annotation.RequestMapping;
-import org.springframework.web.bind.annotation.RequestMethod;
-import org.springframework.web.bind.annotation.RequestParam;
-import org.springframework.web.bind.annotation.RestController;
-
-import java.io.Serializable;
-import java.util.ArrayList;
-import java.util.Collections;
-import java.util.Comparator;
-import java.util.List;
 
 /**
  * Provides access to a user's courses in an LMS such as Moodle.
diff --git a/src/main/java/de/thm/arsnova/controller/v2/FeedbackController.java b/src/main/java/de/thm/arsnova/controller/v2/FeedbackController.java
index 5f7dda308..25b8794c5 100644
--- a/src/main/java/de/thm/arsnova/controller/v2/FeedbackController.java
+++ b/src/main/java/de/thm/arsnova/controller/v2/FeedbackController.java
@@ -15,17 +15,9 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.controller.v2;
 
-import de.thm.arsnova.controller.AbstractController;
-import de.thm.arsnova.model.Feedback;
-import de.thm.arsnova.security.User;
-import de.thm.arsnova.service.FeedbackService;
-import de.thm.arsnova.service.RoomService;
-import de.thm.arsnova.service.UserService;
-import de.thm.arsnova.web.DeprecatedApi;
-import de.thm.arsnova.web.exceptions.NotFoundException;
-import de.thm.arsnova.websocket.ArsnovaSocketioServerImpl;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.MediaType;
@@ -36,6 +28,16 @@ import org.springframework.web.bind.annotation.RequestMethod;
 import org.springframework.web.bind.annotation.ResponseStatus;
 import org.springframework.web.bind.annotation.RestController;
 
+import de.thm.arsnova.controller.AbstractController;
+import de.thm.arsnova.model.Feedback;
+import de.thm.arsnova.security.User;
+import de.thm.arsnova.service.FeedbackService;
+import de.thm.arsnova.service.RoomService;
+import de.thm.arsnova.service.UserService;
+import de.thm.arsnova.web.DeprecatedApi;
+import de.thm.arsnova.web.exceptions.NotFoundException;
+import de.thm.arsnova.websocket.ArsnovaSocketioServerImpl;
+
 /**
  * Handles requests concerning the user's feedback, i.e., "too fast" or "faster, please". This HTTP API is
  * deprecated in favor of the socket implementation.
diff --git a/src/main/java/de/thm/arsnova/controller/v2/LegacyController.java b/src/main/java/de/thm/arsnova/controller/v2/LegacyController.java
index 0e7416219..7389e0a81 100644
--- a/src/main/java/de/thm/arsnova/controller/v2/LegacyController.java
+++ b/src/main/java/de/thm/arsnova/controller/v2/LegacyController.java
@@ -15,12 +15,9 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.controller.v2;
 
-import de.thm.arsnova.controller.AbstractController;
-import de.thm.arsnova.service.CommentService;
-import de.thm.arsnova.service.ContentService;
-import de.thm.arsnova.web.DeprecatedApi;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.stereotype.Controller;
 import org.springframework.web.bind.annotation.PathVariable;
@@ -28,6 +25,11 @@ import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RequestMethod;
 import org.springframework.web.bind.annotation.ResponseBody;
 
+import de.thm.arsnova.controller.AbstractController;
+import de.thm.arsnova.service.CommentService;
+import de.thm.arsnova.service.ContentService;
+import de.thm.arsnova.web.DeprecatedApi;
+
 /**
  * This controller forwards requests from deprecated URLs to their new controller, where the requests are handled.
  */
diff --git a/src/main/java/de/thm/arsnova/controller/v2/MotdController.java b/src/main/java/de/thm/arsnova/controller/v2/MotdController.java
index 31aae6b57..e8790ac0d 100644
--- a/src/main/java/de/thm/arsnova/controller/v2/MotdController.java
+++ b/src/main/java/de/thm/arsnova/controller/v2/MotdController.java
@@ -15,24 +15,18 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.controller.v2;
 
-import de.thm.arsnova.controller.AbstractController;
-import de.thm.arsnova.model.UserProfile;
-import de.thm.arsnova.model.migration.FromV2Migrator;
-import de.thm.arsnova.model.migration.ToV2Migrator;
-import de.thm.arsnova.model.migration.v2.Motd;
-import de.thm.arsnova.model.migration.v2.MotdList;
-import de.thm.arsnova.security.User;
-import de.thm.arsnova.service.MotdService;
-import de.thm.arsnova.service.RoomService;
-import de.thm.arsnova.service.UserService;
-import de.thm.arsnova.web.exceptions.ForbiddenException;
 import io.swagger.annotations.Api;
 import io.swagger.annotations.ApiOperation;
 import io.swagger.annotations.ApiParam;
 import io.swagger.annotations.ApiResponse;
 import io.swagger.annotations.ApiResponses;
+import java.util.Date;
+import java.util.List;
+import java.util.stream.Collectors;
+import javax.servlet.http.HttpServletResponse;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.http.HttpStatus;
 import org.springframework.security.core.annotation.AuthenticationPrincipal;
@@ -44,10 +38,17 @@ import org.springframework.web.bind.annotation.RequestParam;
 import org.springframework.web.bind.annotation.ResponseStatus;
 import org.springframework.web.bind.annotation.RestController;
 
-import javax.servlet.http.HttpServletResponse;
-import java.util.Date;
-import java.util.List;
-import java.util.stream.Collectors;
+import de.thm.arsnova.controller.AbstractController;
+import de.thm.arsnova.model.UserProfile;
+import de.thm.arsnova.model.migration.FromV2Migrator;
+import de.thm.arsnova.model.migration.ToV2Migrator;
+import de.thm.arsnova.model.migration.v2.Motd;
+import de.thm.arsnova.model.migration.v2.MotdList;
+import de.thm.arsnova.security.User;
+import de.thm.arsnova.service.MotdService;
+import de.thm.arsnova.service.RoomService;
+import de.thm.arsnova.service.UserService;
+import de.thm.arsnova.web.exceptions.ForbiddenException;
 
 /**
  *
diff --git a/src/main/java/de/thm/arsnova/controller/v2/RoomController.java b/src/main/java/de/thm/arsnova/controller/v2/RoomController.java
index d7d48c255..33f60a99e 100644
--- a/src/main/java/de/thm/arsnova/controller/v2/RoomController.java
+++ b/src/main/java/de/thm/arsnova/controller/v2/RoomController.java
@@ -15,30 +15,20 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.controller.v2;
 
-import de.thm.arsnova.controller.PaginationController;
-import de.thm.arsnova.model.migration.FromV2Migrator;
-import de.thm.arsnova.model.migration.ToV2Migrator;
-import de.thm.arsnova.model.migration.v2.Room;
-import de.thm.arsnova.model.migration.v2.RoomFeature;
-import de.thm.arsnova.model.migration.v2.RoomInfo;
-import de.thm.arsnova.model.transport.ImportExportContainer;
-import de.thm.arsnova.model.transport.ScoreStatistics;
-import de.thm.arsnova.service.RoomService;
-import de.thm.arsnova.service.RoomServiceImpl;
-import de.thm.arsnova.service.RoomServiceImpl.RoomNameComparator;
-import de.thm.arsnova.service.RoomServiceImpl.RoomShortNameComparator;
-import de.thm.arsnova.service.UserService;
-import de.thm.arsnova.web.DeprecatedApi;
-import de.thm.arsnova.web.Pagination;
-import de.thm.arsnova.web.exceptions.NotImplementedException;
-import de.thm.arsnova.web.exceptions.UnauthorizedException;
 import io.swagger.annotations.Api;
 import io.swagger.annotations.ApiOperation;
 import io.swagger.annotations.ApiParam;
 import io.swagger.annotations.ApiResponse;
 import io.swagger.annotations.ApiResponses;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import java.util.stream.Collectors;
+import javax.servlet.http.HttpServletResponse;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.MediaType;
@@ -51,12 +41,23 @@ import org.springframework.web.bind.annotation.RequestParam;
 import org.springframework.web.bind.annotation.ResponseStatus;
 import org.springframework.web.bind.annotation.RestController;
 
-import javax.servlet.http.HttpServletResponse;
-import java.io.IOException;
-import java.util.ArrayList;
-import java.util.Collections;
-import java.util.List;
-import java.util.stream.Collectors;
+import de.thm.arsnova.controller.PaginationController;
+import de.thm.arsnova.model.migration.FromV2Migrator;
+import de.thm.arsnova.model.migration.ToV2Migrator;
+import de.thm.arsnova.model.migration.v2.Room;
+import de.thm.arsnova.model.migration.v2.RoomFeature;
+import de.thm.arsnova.model.migration.v2.RoomInfo;
+import de.thm.arsnova.model.transport.ImportExportContainer;
+import de.thm.arsnova.model.transport.ScoreStatistics;
+import de.thm.arsnova.service.RoomService;
+import de.thm.arsnova.service.RoomServiceImpl;
+import de.thm.arsnova.service.RoomServiceImpl.RoomNameComparator;
+import de.thm.arsnova.service.RoomServiceImpl.RoomShortNameComparator;
+import de.thm.arsnova.service.UserService;
+import de.thm.arsnova.web.DeprecatedApi;
+import de.thm.arsnova.web.Pagination;
+import de.thm.arsnova.web.exceptions.NotImplementedException;
+import de.thm.arsnova.web.exceptions.UnauthorizedException;
 
 /**
  * Handles requests related to ARSnova Rooms.
diff --git a/src/main/java/de/thm/arsnova/controller/v2/SocketController.java b/src/main/java/de/thm/arsnova/controller/v2/SocketController.java
index 00bf63f0a..87565833d 100644
--- a/src/main/java/de/thm/arsnova/controller/v2/SocketController.java
+++ b/src/main/java/de/thm/arsnova/controller/v2/SocketController.java
@@ -15,17 +15,18 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.controller.v2;
 
-import de.thm.arsnova.controller.AbstractController;
-import de.thm.arsnova.security.User;
-import de.thm.arsnova.service.UserService;
-import de.thm.arsnova.websocket.ArsnovaSocketioServer;
 import io.swagger.annotations.Api;
 import io.swagger.annotations.ApiOperation;
 import io.swagger.annotations.ApiParam;
 import io.swagger.annotations.ApiResponse;
 import io.swagger.annotations.ApiResponses;
+import java.util.Map;
+import java.util.UUID;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.beans.factory.annotation.Autowired;
@@ -36,10 +37,10 @@ import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RequestMethod;
 import org.springframework.web.bind.annotation.RestController;
 
-import javax.servlet.http.HttpServletRequest;
-import javax.servlet.http.HttpServletResponse;
-import java.util.Map;
-import java.util.UUID;
+import de.thm.arsnova.controller.AbstractController;
+import de.thm.arsnova.security.User;
+import de.thm.arsnova.service.UserService;
+import de.thm.arsnova.websocket.ArsnovaSocketioServer;
 
 /**
  * Initiates the socket communication.
diff --git a/src/main/java/de/thm/arsnova/controller/v2/StatisticsController.java b/src/main/java/de/thm/arsnova/controller/v2/StatisticsController.java
index 88ccbf36e..8fea0e16a 100644
--- a/src/main/java/de/thm/arsnova/controller/v2/StatisticsController.java
+++ b/src/main/java/de/thm/arsnova/controller/v2/StatisticsController.java
@@ -15,13 +15,9 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.controller.v2;
 
-import de.thm.arsnova.controller.AbstractController;
-import de.thm.arsnova.model.Statistics;
-import de.thm.arsnova.service.StatisticsService;
-import de.thm.arsnova.web.CacheControl;
-import de.thm.arsnova.web.DeprecatedApi;
 import io.swagger.annotations.Api;
 import io.swagger.annotations.ApiOperation;
 import org.springframework.beans.factory.annotation.Autowired;
@@ -30,6 +26,12 @@ import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RequestMethod;
 import org.springframework.web.bind.annotation.RestController;
 
+import de.thm.arsnova.controller.AbstractController;
+import de.thm.arsnova.model.Statistics;
+import de.thm.arsnova.service.StatisticsService;
+import de.thm.arsnova.web.CacheControl;
+import de.thm.arsnova.web.DeprecatedApi;
+
 /**
  * Allows retrieval of several statistics such as the number of active users.
  */
diff --git a/src/main/java/de/thm/arsnova/controller/v2/UserController.java b/src/main/java/de/thm/arsnova/controller/v2/UserController.java
index 72c88a662..5bd9c30aa 100644
--- a/src/main/java/de/thm/arsnova/controller/v2/UserController.java
+++ b/src/main/java/de/thm/arsnova/controller/v2/UserController.java
@@ -15,11 +15,11 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.controller.v2;
 
-import de.thm.arsnova.controller.AbstractController;
-import de.thm.arsnova.model.UserProfile;
-import de.thm.arsnova.service.UserService;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.security.authentication.dao.DaoAuthenticationProvider;
 import org.springframework.stereotype.Controller;
@@ -28,8 +28,9 @@ import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RequestMethod;
 import org.springframework.web.bind.annotation.RequestParam;
 
-import javax.servlet.http.HttpServletRequest;
-import javax.servlet.http.HttpServletResponse;
+import de.thm.arsnova.controller.AbstractController;
+import de.thm.arsnova.model.UserProfile;
+import de.thm.arsnova.service.UserService;
 
 /**
  * Handles requests related to ARSnova's own user registration and login process.
diff --git a/src/main/java/de/thm/arsnova/event/AfterCreationEvent.java b/src/main/java/de/thm/arsnova/event/AfterCreationEvent.java
index 6c35146c9..7901103dd 100644
--- a/src/main/java/de/thm/arsnova/event/AfterCreationEvent.java
+++ b/src/main/java/de/thm/arsnova/event/AfterCreationEvent.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.event;
 
 import de.thm.arsnova.model.Entity;
diff --git a/src/main/java/de/thm/arsnova/event/AfterDeletionEvent.java b/src/main/java/de/thm/arsnova/event/AfterDeletionEvent.java
index 6a633db9b..e53a16ec2 100644
--- a/src/main/java/de/thm/arsnova/event/AfterDeletionEvent.java
+++ b/src/main/java/de/thm/arsnova/event/AfterDeletionEvent.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.event;
 
 import de.thm.arsnova.model.Entity;
diff --git a/src/main/java/de/thm/arsnova/event/AfterFullUpdateEvent.java b/src/main/java/de/thm/arsnova/event/AfterFullUpdateEvent.java
index ae23ce044..9e3129dc3 100644
--- a/src/main/java/de/thm/arsnova/event/AfterFullUpdateEvent.java
+++ b/src/main/java/de/thm/arsnova/event/AfterFullUpdateEvent.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.event;
 
 import de.thm.arsnova.model.Entity;
diff --git a/src/main/java/de/thm/arsnova/event/AfterPatchEvent.java b/src/main/java/de/thm/arsnova/event/AfterPatchEvent.java
index c79d2ae31..e58fb3d47 100644
--- a/src/main/java/de/thm/arsnova/event/AfterPatchEvent.java
+++ b/src/main/java/de/thm/arsnova/event/AfterPatchEvent.java
@@ -15,13 +15,14 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-package de.thm.arsnova.event;
 
-import de.thm.arsnova.model.Entity;
+package de.thm.arsnova.event;
 
 import java.util.Map;
 import java.util.function.Function;
 
+import de.thm.arsnova.model.Entity;
+
 public class AfterPatchEvent<E extends Entity> extends AfterUpdateEvent<E> {
 	private final Function<E, ? extends Object> propertyGetter;
 	private final Map<String, Object> changes;
diff --git a/src/main/java/de/thm/arsnova/event/AfterUpdateEvent.java b/src/main/java/de/thm/arsnova/event/AfterUpdateEvent.java
index 688f9b8ee..88ed16d77 100644
--- a/src/main/java/de/thm/arsnova/event/AfterUpdateEvent.java
+++ b/src/main/java/de/thm/arsnova/event/AfterUpdateEvent.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.event;
 
 import de.thm.arsnova.model.Entity;
diff --git a/src/main/java/de/thm/arsnova/event/ArsnovaEvent.java b/src/main/java/de/thm/arsnova/event/ArsnovaEvent.java
index eff061f27..66d51c083 100644
--- a/src/main/java/de/thm/arsnova/event/ArsnovaEvent.java
+++ b/src/main/java/de/thm/arsnova/event/ArsnovaEvent.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.event;
 
 import org.springframework.context.ApplicationEvent;
diff --git a/src/main/java/de/thm/arsnova/event/BeforeCreationEvent.java b/src/main/java/de/thm/arsnova/event/BeforeCreationEvent.java
index da000310a..391bd0d81 100644
--- a/src/main/java/de/thm/arsnova/event/BeforeCreationEvent.java
+++ b/src/main/java/de/thm/arsnova/event/BeforeCreationEvent.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.event;
 
 import de.thm.arsnova.model.Entity;
diff --git a/src/main/java/de/thm/arsnova/event/BeforeDeletionEvent.java b/src/main/java/de/thm/arsnova/event/BeforeDeletionEvent.java
index c2239b8e4..ca1ac9228 100644
--- a/src/main/java/de/thm/arsnova/event/BeforeDeletionEvent.java
+++ b/src/main/java/de/thm/arsnova/event/BeforeDeletionEvent.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.event;
 
 import de.thm.arsnova.model.Entity;
diff --git a/src/main/java/de/thm/arsnova/event/BeforeFullUpdateEvent.java b/src/main/java/de/thm/arsnova/event/BeforeFullUpdateEvent.java
index 5f4b350cd..d7f3e82ba 100644
--- a/src/main/java/de/thm/arsnova/event/BeforeFullUpdateEvent.java
+++ b/src/main/java/de/thm/arsnova/event/BeforeFullUpdateEvent.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.event;
 
 import de.thm.arsnova.model.Entity;
diff --git a/src/main/java/de/thm/arsnova/event/BeforePatchEvent.java b/src/main/java/de/thm/arsnova/event/BeforePatchEvent.java
index d2d5070b6..a73771e3c 100644
--- a/src/main/java/de/thm/arsnova/event/BeforePatchEvent.java
+++ b/src/main/java/de/thm/arsnova/event/BeforePatchEvent.java
@@ -15,13 +15,14 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-package de.thm.arsnova.event;
 
-import de.thm.arsnova.model.Entity;
+package de.thm.arsnova.event;
 
 import java.util.Map;
 import java.util.function.Function;
 
+import de.thm.arsnova.model.Entity;
+
 public class BeforePatchEvent<E extends Entity> extends BeforeUpdateEvent<E> {
 	private final Function<E, ? extends Object> propertyGetter;
 	private final Map<String, Object> changes;
diff --git a/src/main/java/de/thm/arsnova/event/BeforeUpdateEvent.java b/src/main/java/de/thm/arsnova/event/BeforeUpdateEvent.java
index 450f9ea5f..7f0ce2db6 100644
--- a/src/main/java/de/thm/arsnova/event/BeforeUpdateEvent.java
+++ b/src/main/java/de/thm/arsnova/event/BeforeUpdateEvent.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.event;
 
 import de.thm.arsnova.model.Entity;
diff --git a/src/main/java/de/thm/arsnova/event/ChangeScoreEvent.java b/src/main/java/de/thm/arsnova/event/ChangeScoreEvent.java
index 62937cb3f..4dc188ddd 100644
--- a/src/main/java/de/thm/arsnova/event/ChangeScoreEvent.java
+++ b/src/main/java/de/thm/arsnova/event/ChangeScoreEvent.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.event;
 
 /**
diff --git a/src/main/java/de/thm/arsnova/event/CrudEvent.java b/src/main/java/de/thm/arsnova/event/CrudEvent.java
index cf53ad1ec..fbe1ebf46 100644
--- a/src/main/java/de/thm/arsnova/event/CrudEvent.java
+++ b/src/main/java/de/thm/arsnova/event/CrudEvent.java
@@ -15,13 +15,15 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.event;
 
-import de.thm.arsnova.model.Entity;
 import org.springframework.context.ApplicationEvent;
 import org.springframework.core.ResolvableType;
 import org.springframework.core.ResolvableTypeProvider;
 
+import de.thm.arsnova.model.Entity;
+
 public abstract class CrudEvent<E extends Entity> extends ApplicationEvent implements ResolvableTypeProvider {
 	private E entity;
 
diff --git a/src/main/java/de/thm/arsnova/event/DeleteFeedbackForRoomsEvent.java b/src/main/java/de/thm/arsnova/event/DeleteFeedbackForRoomsEvent.java
index aec470947..45729339f 100644
--- a/src/main/java/de/thm/arsnova/event/DeleteFeedbackForRoomsEvent.java
+++ b/src/main/java/de/thm/arsnova/event/DeleteFeedbackForRoomsEvent.java
@@ -15,12 +15,13 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-package de.thm.arsnova.event;
 
-import de.thm.arsnova.model.Room;
+package de.thm.arsnova.event;
 
 import java.util.Set;
 
+import de.thm.arsnova.model.Room;
+
 /**
  * Fires whenever the feedback of a specific user has been reset.
  */
diff --git a/src/main/java/de/thm/arsnova/event/FlipFlashcardsEvent.java b/src/main/java/de/thm/arsnova/event/FlipFlashcardsEvent.java
index 8099d2bf5..73abd1b11 100644
--- a/src/main/java/de/thm/arsnova/event/FlipFlashcardsEvent.java
+++ b/src/main/java/de/thm/arsnova/event/FlipFlashcardsEvent.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.event;
 
 /**
diff --git a/src/main/java/de/thm/arsnova/event/NewFeedbackEvent.java b/src/main/java/de/thm/arsnova/event/NewFeedbackEvent.java
index 9d3df37a0..07e54276a 100644
--- a/src/main/java/de/thm/arsnova/event/NewFeedbackEvent.java
+++ b/src/main/java/de/thm/arsnova/event/NewFeedbackEvent.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.event;
 
 /**
diff --git a/src/main/java/de/thm/arsnova/event/RoomEvent.java b/src/main/java/de/thm/arsnova/event/RoomEvent.java
index 5af8668ed..93352387b 100644
--- a/src/main/java/de/thm/arsnova/event/RoomEvent.java
+++ b/src/main/java/de/thm/arsnova/event/RoomEvent.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.event;
 
 /**
diff --git a/src/main/java/de/thm/arsnova/event/StateChangeEvent.java b/src/main/java/de/thm/arsnova/event/StateChangeEvent.java
index ccb1d3694..906fef62b 100644
--- a/src/main/java/de/thm/arsnova/event/StateChangeEvent.java
+++ b/src/main/java/de/thm/arsnova/event/StateChangeEvent.java
@@ -15,14 +15,15 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.event;
 
-import de.thm.arsnova.model.Entity;
+import java.util.Optional;
 import org.springframework.context.ApplicationEvent;
 import org.springframework.core.ResolvableType;
 import org.springframework.core.ResolvableTypeProvider;
 
-import java.util.Optional;
+import de.thm.arsnova.model.Entity;
 
 public class StateChangeEvent<E extends Entity, T> extends ApplicationEvent implements ResolvableTypeProvider {
 	private final E entity;
diff --git a/src/main/java/de/thm/arsnova/event/StateEventDispatcher.java b/src/main/java/de/thm/arsnova/event/StateEventDispatcher.java
index 0d63bcec6..227f3f0ae 100644
--- a/src/main/java/de/thm/arsnova/event/StateEventDispatcher.java
+++ b/src/main/java/de/thm/arsnova/event/StateEventDispatcher.java
@@ -15,18 +15,19 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.event;
 
-import de.thm.arsnova.model.Content;
-import de.thm.arsnova.model.Entity;
-import de.thm.arsnova.model.Room;
+import java.util.Map;
+import java.util.function.Function;
 import org.springframework.context.ApplicationEventPublisher;
 import org.springframework.context.ApplicationEventPublisherAware;
 import org.springframework.context.event.EventListener;
 import org.springframework.stereotype.Component;
 
-import java.util.Map;
-import java.util.function.Function;
+import de.thm.arsnova.model.Content;
+import de.thm.arsnova.model.Entity;
+import de.thm.arsnova.model.Room;
 
 /**
  * StateEventDispatcher publishes additional, more specific events for state changes of entities when
diff --git a/src/main/java/de/thm/arsnova/event/package-info.java b/src/main/java/de/thm/arsnova/event/package-info.java
index 636c0e300..d1ffd4be2 100644
--- a/src/main/java/de/thm/arsnova/event/package-info.java
+++ b/src/main/java/de/thm/arsnova/event/package-info.java
@@ -1,4 +1,5 @@
 /**
  * ARSnova's internal event system
  */
+
 package de.thm.arsnova.event;
diff --git a/src/main/java/de/thm/arsnova/model/Answer.java b/src/main/java/de/thm/arsnova/model/Answer.java
index 1c3387227..4f9e6322a 100644
--- a/src/main/java/de/thm/arsnova/model/Answer.java
+++ b/src/main/java/de/thm/arsnova/model/Answer.java
@@ -15,17 +15,18 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model;
 
 import com.fasterxml.jackson.annotation.JsonTypeInfo;
 import com.fasterxml.jackson.annotation.JsonView;
 import com.fasterxml.jackson.databind.annotation.JsonTypeIdResolver;
-import de.thm.arsnova.model.serialization.FormatAnswerTypeIdResolver;
-import de.thm.arsnova.model.serialization.View;
-import org.springframework.core.style.ToStringCreator;
-
 import java.util.Map;
 import java.util.Objects;
+import org.springframework.core.style.ToStringCreator;
+
+import de.thm.arsnova.model.serialization.FormatAnswerTypeIdResolver;
+import de.thm.arsnova.model.serialization.View;
 
 @JsonTypeInfo(
 		use = JsonTypeInfo.Id.CUSTOM,
diff --git a/src/main/java/de/thm/arsnova/model/AnswerStatistics.java b/src/main/java/de/thm/arsnova/model/AnswerStatistics.java
index 611888e41..a0a9f049c 100644
--- a/src/main/java/de/thm/arsnova/model/AnswerStatistics.java
+++ b/src/main/java/de/thm/arsnova/model/AnswerStatistics.java
@@ -15,14 +15,15 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model;
 
 import com.fasterxml.jackson.annotation.JsonView;
-import de.thm.arsnova.model.serialization.View;
-import org.springframework.core.style.ToStringCreator;
-
 import java.util.Collection;
 import java.util.List;
+import org.springframework.core.style.ToStringCreator;
+
+import de.thm.arsnova.model.serialization.View;
 
 public class AnswerStatistics {
 	public static class RoundStatistics {
diff --git a/src/main/java/de/thm/arsnova/model/Attachment.java b/src/main/java/de/thm/arsnova/model/Attachment.java
index ed72909ae..9eed32198 100644
--- a/src/main/java/de/thm/arsnova/model/Attachment.java
+++ b/src/main/java/de/thm/arsnova/model/Attachment.java
@@ -15,13 +15,14 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model;
 
 import com.fasterxml.jackson.annotation.JsonView;
-import de.thm.arsnova.model.serialization.View;
+import java.util.Objects;
 import org.springframework.core.style.ToStringCreator;
 
-import java.util.Objects;
+import de.thm.arsnova.model.serialization.View;
 
 public class Attachment extends Entity {
 	private String mediaType;
diff --git a/src/main/java/de/thm/arsnova/model/Authorize.java b/src/main/java/de/thm/arsnova/model/Authorize.java
index ac3a9c8db..04353a6a8 100644
--- a/src/main/java/de/thm/arsnova/model/Authorize.java
+++ b/src/main/java/de/thm/arsnova/model/Authorize.java
@@ -15,9 +15,11 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model;
 
 import com.fasterxml.jackson.annotation.JsonView;
+
 import de.thm.arsnova.model.serialization.View;
 
 public class Authorize {
diff --git a/src/main/java/de/thm/arsnova/model/ChoiceAnswer.java b/src/main/java/de/thm/arsnova/model/ChoiceAnswer.java
index 8b1245c78..25fb49606 100644
--- a/src/main/java/de/thm/arsnova/model/ChoiceAnswer.java
+++ b/src/main/java/de/thm/arsnova/model/ChoiceAnswer.java
@@ -15,13 +15,14 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model;
 
 import com.fasterxml.jackson.annotation.JsonView;
-import de.thm.arsnova.model.serialization.View;
+import java.util.List;
 import org.springframework.core.style.ToStringCreator;
 
-import java.util.List;
+import de.thm.arsnova.model.serialization.View;
 
 public class ChoiceAnswer extends Answer {
 	private List<Integer> selectedChoiceIndexes;
diff --git a/src/main/java/de/thm/arsnova/model/ChoiceQuestionContent.java b/src/main/java/de/thm/arsnova/model/ChoiceQuestionContent.java
index 4d4f258f9..fa7797b89 100644
--- a/src/main/java/de/thm/arsnova/model/ChoiceQuestionContent.java
+++ b/src/main/java/de/thm/arsnova/model/ChoiceQuestionContent.java
@@ -15,15 +15,16 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model;
 
 import com.fasterxml.jackson.annotation.JsonView;
-import de.thm.arsnova.model.serialization.View;
-import org.springframework.core.style.ToStringCreator;
-
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Objects;
+import org.springframework.core.style.ToStringCreator;
+
+import de.thm.arsnova.model.serialization.View;
 
 public class ChoiceQuestionContent extends Content {
 	public static class AnswerOption {
diff --git a/src/main/java/de/thm/arsnova/model/ClientAuthentication.java b/src/main/java/de/thm/arsnova/model/ClientAuthentication.java
index 06c5d8885..98f588d90 100644
--- a/src/main/java/de/thm/arsnova/model/ClientAuthentication.java
+++ b/src/main/java/de/thm/arsnova/model/ClientAuthentication.java
@@ -15,12 +15,14 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model;
 
 import com.fasterxml.jackson.annotation.JsonView;
-import de.thm.arsnova.model.serialization.View;
 import org.springframework.core.style.ToStringCreator;
 
+import de.thm.arsnova.model.serialization.View;
+
 public class ClientAuthentication {
 	private String userId;
 	private String loginId;
diff --git a/src/main/java/de/thm/arsnova/model/Comment.java b/src/main/java/de/thm/arsnova/model/Comment.java
index 686903cc5..46267287a 100644
--- a/src/main/java/de/thm/arsnova/model/Comment.java
+++ b/src/main/java/de/thm/arsnova/model/Comment.java
@@ -15,15 +15,16 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model;
 
 import com.fasterxml.jackson.annotation.JsonView;
-import de.thm.arsnova.model.serialization.View;
-import org.springframework.core.style.ToStringCreator;
-
 import java.util.Date;
 import java.util.Map;
 import java.util.Objects;
+import org.springframework.core.style.ToStringCreator;
+
+import de.thm.arsnova.model.serialization.View;
 
 public class Comment extends Entity {
 	private String roomId;
diff --git a/src/main/java/de/thm/arsnova/model/Content.java b/src/main/java/de/thm/arsnova/model/Content.java
index b015f53de..a388f70ee 100644
--- a/src/main/java/de/thm/arsnova/model/Content.java
+++ b/src/main/java/de/thm/arsnova/model/Content.java
@@ -15,20 +15,21 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model;
 
 import com.fasterxml.jackson.annotation.JsonTypeInfo;
 import com.fasterxml.jackson.annotation.JsonView;
 import com.fasterxml.jackson.databind.annotation.JsonTypeIdResolver;
-import de.thm.arsnova.model.serialization.FormatContentTypeIdResolver;
-import de.thm.arsnova.model.serialization.View;
-import org.springframework.core.style.ToStringCreator;
-
 import java.util.Date;
 import java.util.HashSet;
 import java.util.Map;
 import java.util.Objects;
 import java.util.Set;
+import org.springframework.core.style.ToStringCreator;
+
+import de.thm.arsnova.model.serialization.FormatContentTypeIdResolver;
+import de.thm.arsnova.model.serialization.View;
 
 @JsonTypeInfo(
 		use = JsonTypeInfo.Id.CUSTOM,
diff --git a/src/main/java/de/thm/arsnova/model/Entity.java b/src/main/java/de/thm/arsnova/model/Entity.java
index 33deacb3e..b5292c40d 100644
--- a/src/main/java/de/thm/arsnova/model/Entity.java
+++ b/src/main/java/de/thm/arsnova/model/Entity.java
@@ -15,14 +15,15 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model;
 
 import com.fasterxml.jackson.annotation.JsonView;
-import de.thm.arsnova.model.serialization.View;
-import org.springframework.core.style.ToStringCreator;
-
 import java.util.Date;
 import java.util.Objects;
+import org.springframework.core.style.ToStringCreator;
+
+import de.thm.arsnova.model.serialization.View;
 
 /**
  * Used as base for classes that represent persistent data with an unique ID.
diff --git a/src/main/java/de/thm/arsnova/model/Feedback.java b/src/main/java/de/thm/arsnova/model/Feedback.java
index 13fa25df0..c64521796 100644
--- a/src/main/java/de/thm/arsnova/model/Feedback.java
+++ b/src/main/java/de/thm/arsnova/model/Feedback.java
@@ -15,15 +15,16 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model;
 
 import com.fasterxml.jackson.annotation.JsonView;
-import de.thm.arsnova.model.serialization.View;
-
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Optional;
 
+import de.thm.arsnova.model.serialization.View;
+
 /**
  * The feedback values of a single session.
  */
diff --git a/src/main/java/de/thm/arsnova/model/FindQuery.java b/src/main/java/de/thm/arsnova/model/FindQuery.java
index 51915ebdc..5391f1f83 100644
--- a/src/main/java/de/thm/arsnova/model/FindQuery.java
+++ b/src/main/java/de/thm/arsnova/model/FindQuery.java
@@ -15,13 +15,14 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model;
 
 import com.fasterxml.jackson.annotation.JsonView;
-import de.thm.arsnova.model.serialization.View;
+import java.util.Map;
 import org.springframework.core.style.ToStringCreator;
 
-import java.util.Map;
+import de.thm.arsnova.model.serialization.View;
 
 public class FindQuery<E extends Entity> {
 	enum LogicalOperator {
diff --git a/src/main/java/de/thm/arsnova/model/LogEntry.java b/src/main/java/de/thm/arsnova/model/LogEntry.java
index d1e60ea15..b21183b32 100644
--- a/src/main/java/de/thm/arsnova/model/LogEntry.java
+++ b/src/main/java/de/thm/arsnova/model/LogEntry.java
@@ -15,16 +15,17 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model;
 
 import com.fasterxml.jackson.annotation.JsonProperty;
 import com.fasterxml.jackson.annotation.JsonView;
-import de.thm.arsnova.model.serialization.View;
-
 import java.util.Date;
 import java.util.Map;
 import java.util.Objects;
 
+import de.thm.arsnova.model.serialization.View;
+
 public class LogEntry extends Entity {
 	public enum LogLevel {
 		TRACE,
diff --git a/src/main/java/de/thm/arsnova/model/LoginCredentials.java b/src/main/java/de/thm/arsnova/model/LoginCredentials.java
index caeb74a4f..b847424c0 100644
--- a/src/main/java/de/thm/arsnova/model/LoginCredentials.java
+++ b/src/main/java/de/thm/arsnova/model/LoginCredentials.java
@@ -15,12 +15,14 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model;
 
 import com.fasterxml.jackson.annotation.JsonView;
-import de.thm.arsnova.model.serialization.View;
 import org.springframework.core.style.ToStringCreator;
 
+import de.thm.arsnova.model.serialization.View;
+
 public class LoginCredentials {
 	private String loginId;
 	private String password;
diff --git a/src/main/java/de/thm/arsnova/model/MigrationState.java b/src/main/java/de/thm/arsnova/model/MigrationState.java
index 96c83265f..bbcabb50b 100644
--- a/src/main/java/de/thm/arsnova/model/MigrationState.java
+++ b/src/main/java/de/thm/arsnova/model/MigrationState.java
@@ -15,16 +15,17 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model;
 
 import com.fasterxml.jackson.annotation.JsonView;
-import de.thm.arsnova.model.serialization.View;
-
 import java.util.ArrayList;
 import java.util.Date;
 import java.util.List;
 import java.util.Objects;
 
+import de.thm.arsnova.model.serialization.View;
+
 public class MigrationState extends Entity {
 	public static class Migration {
 		private String id;
diff --git a/src/main/java/de/thm/arsnova/model/Motd.java b/src/main/java/de/thm/arsnova/model/Motd.java
index ec70d83b8..0f5729aee 100644
--- a/src/main/java/de/thm/arsnova/model/Motd.java
+++ b/src/main/java/de/thm/arsnova/model/Motd.java
@@ -15,14 +15,15 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model;
 
 import com.fasterxml.jackson.annotation.JsonView;
-import de.thm.arsnova.model.serialization.View;
-import org.springframework.core.style.ToStringCreator;
-
 import java.util.Date;
 import java.util.Objects;
+import org.springframework.core.style.ToStringCreator;
+
+import de.thm.arsnova.model.serialization.View;
 
 public class Motd extends Entity {
 	public enum Audience {
diff --git a/src/main/java/de/thm/arsnova/model/Room.java b/src/main/java/de/thm/arsnova/model/Room.java
index 12caac41e..006acda6c 100644
--- a/src/main/java/de/thm/arsnova/model/Room.java
+++ b/src/main/java/de/thm/arsnova/model/Room.java
@@ -15,18 +15,19 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model;
 
 import com.fasterxml.jackson.annotation.JsonView;
-import de.thm.arsnova.model.serialization.View;
-import org.springframework.core.style.ToStringCreator;
-
 import java.util.HashSet;
 import java.util.Map;
 import java.util.Objects;
 import java.util.Set;
 import java.util.function.Function;
 import java.util.stream.Collectors;
+import org.springframework.core.style.ToStringCreator;
+
+import de.thm.arsnova.model.serialization.View;
 
 public class Room extends Entity {
 	public static class ContentGroup {
diff --git a/src/main/java/de/thm/arsnova/model/RoomStatistics.java b/src/main/java/de/thm/arsnova/model/RoomStatistics.java
index da1ebba60..d15d0cae9 100644
--- a/src/main/java/de/thm/arsnova/model/RoomStatistics.java
+++ b/src/main/java/de/thm/arsnova/model/RoomStatistics.java
@@ -15,12 +15,14 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model;
 
 import com.fasterxml.jackson.annotation.JsonView;
-import de.thm.arsnova.model.serialization.View;
 import org.springframework.core.style.ToStringCreator;
 
+import de.thm.arsnova.model.serialization.View;
+
 public class RoomStatistics {
 	private int contentCount = 0;
 	private int unansweredContentCount = 0;
diff --git a/src/main/java/de/thm/arsnova/model/ScoreOptions.java b/src/main/java/de/thm/arsnova/model/ScoreOptions.java
index bc16b95d7..7a04e3e1c 100644
--- a/src/main/java/de/thm/arsnova/model/ScoreOptions.java
+++ b/src/main/java/de/thm/arsnova/model/ScoreOptions.java
@@ -15,15 +15,16 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model;
 
 import com.fasterxml.jackson.annotation.JsonView;
-import de.thm.arsnova.model.serialization.View;
 import io.swagger.annotations.ApiModel;
 import io.swagger.annotations.ApiModelProperty;
-
 import java.io.Serializable;
 
+import de.thm.arsnova.model.serialization.View;
+
 /**
  * A session's settings regarding the calculation of the score.
  */
diff --git a/src/main/java/de/thm/arsnova/model/ServiceDescription.java b/src/main/java/de/thm/arsnova/model/ServiceDescription.java
index 755c48bf4..5b9c6c4e4 100644
--- a/src/main/java/de/thm/arsnova/model/ServiceDescription.java
+++ b/src/main/java/de/thm/arsnova/model/ServiceDescription.java
@@ -15,9 +15,11 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model;
 
 import com.fasterxml.jackson.annotation.JsonView;
+
 import de.thm.arsnova.model.serialization.View;
 
 /**
diff --git a/src/main/java/de/thm/arsnova/model/Statistics.java b/src/main/java/de/thm/arsnova/model/Statistics.java
index d73b544f8..e8ab39f19 100644
--- a/src/main/java/de/thm/arsnova/model/Statistics.java
+++ b/src/main/java/de/thm/arsnova/model/Statistics.java
@@ -15,13 +15,15 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model;
 
 import com.fasterxml.jackson.annotation.JsonView;
-import de.thm.arsnova.model.serialization.View;
 import io.swagger.annotations.ApiModel;
 import io.swagger.annotations.ApiModelProperty;
 
+import de.thm.arsnova.model.serialization.View;
+
 /**
  * Collection of several statistics about ARSnova.
  */
diff --git a/src/main/java/de/thm/arsnova/model/TextAnswer.java b/src/main/java/de/thm/arsnova/model/TextAnswer.java
index a1226fdbb..ac84b9d59 100644
--- a/src/main/java/de/thm/arsnova/model/TextAnswer.java
+++ b/src/main/java/de/thm/arsnova/model/TextAnswer.java
@@ -15,13 +15,14 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model;
 
 import com.fasterxml.jackson.annotation.JsonView;
-import de.thm.arsnova.model.serialization.View;
+import java.util.Date;
 import org.springframework.core.style.ToStringCreator;
 
-import java.util.Date;
+import de.thm.arsnova.model.serialization.View;
 
 public class TextAnswer extends Answer {
 	private String subject;
diff --git a/src/main/java/de/thm/arsnova/model/UserProfile.java b/src/main/java/de/thm/arsnova/model/UserProfile.java
index 58425835d..31a6c94c5 100644
--- a/src/main/java/de/thm/arsnova/model/UserProfile.java
+++ b/src/main/java/de/thm/arsnova/model/UserProfile.java
@@ -15,17 +15,18 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model;
 
 import com.fasterxml.jackson.annotation.JsonView;
-import de.thm.arsnova.model.serialization.View;
-import org.springframework.core.style.ToStringCreator;
-
 import java.util.Date;
 import java.util.HashSet;
 import java.util.Map;
 import java.util.Objects;
 import java.util.Set;
+import org.springframework.core.style.ToStringCreator;
+
+import de.thm.arsnova.model.serialization.View;
 
 public class UserProfile extends Entity {
 	public enum AuthProvider {
diff --git a/src/main/java/de/thm/arsnova/model/migration/FromV2Migrator.java b/src/main/java/de/thm/arsnova/model/migration/FromV2Migrator.java
index 27605454b..03816a662 100644
--- a/src/main/java/de/thm/arsnova/model/migration/FromV2Migrator.java
+++ b/src/main/java/de/thm/arsnova/model/migration/FromV2Migrator.java
@@ -15,14 +15,8 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-package de.thm.arsnova.model.migration;
 
-import de.thm.arsnova.model.ChoiceAnswer;
-import de.thm.arsnova.model.ChoiceQuestionContent;
-import de.thm.arsnova.model.TextAnswer;
-import de.thm.arsnova.model.UserProfile;
-import de.thm.arsnova.model.migration.v2.*;
-import org.checkerframework.checker.nullness.qual.Nullable;
+package de.thm.arsnova.model.migration;
 
 import java.util.ArrayList;
 import java.util.Arrays;
@@ -33,6 +27,22 @@ import java.util.Map;
 import java.util.Optional;
 import java.util.Set;
 import java.util.stream.Collectors;
+import org.checkerframework.checker.nullness.qual.Nullable;
+
+import de.thm.arsnova.model.ChoiceAnswer;
+import de.thm.arsnova.model.ChoiceQuestionContent;
+import de.thm.arsnova.model.TextAnswer;
+import de.thm.arsnova.model.UserProfile;
+import de.thm.arsnova.model.migration.v2.Answer;
+import de.thm.arsnova.model.migration.v2.Comment;
+import de.thm.arsnova.model.migration.v2.Content;
+import de.thm.arsnova.model.migration.v2.DbUser;
+import de.thm.arsnova.model.migration.v2.Entity;
+import de.thm.arsnova.model.migration.v2.LoggedIn;
+import de.thm.arsnova.model.migration.v2.Motd;
+import de.thm.arsnova.model.migration.v2.MotdList;
+import de.thm.arsnova.model.migration.v2.Room;
+import de.thm.arsnova.model.migration.v2.RoomFeature;
 
 /**
  * Converts legacy entities from version 2 to current model version.
diff --git a/src/main/java/de/thm/arsnova/model/migration/ToV2Migrator.java b/src/main/java/de/thm/arsnova/model/migration/ToV2Migrator.java
index 6cece70c7..b6b3b17e0 100644
--- a/src/main/java/de/thm/arsnova/model/migration/ToV2Migrator.java
+++ b/src/main/java/de/thm/arsnova/model/migration/ToV2Migrator.java
@@ -15,13 +15,16 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model.migration;
 
-import de.thm.arsnova.model.AnswerStatistics;
-import de.thm.arsnova.model.ChoiceQuestionContent;
-import de.thm.arsnova.model.RoomStatistics;
-import de.thm.arsnova.model.UserProfile;
-import de.thm.arsnova.model.migration.v2.*;
+import static de.thm.arsnova.model.migration.FromV2Migrator.V2_TYPE_ABCD;
+import static de.thm.arsnova.model.migration.FromV2Migrator.V2_TYPE_FREETEXT;
+import static de.thm.arsnova.model.migration.FromV2Migrator.V2_TYPE_GRID;
+import static de.thm.arsnova.model.migration.FromV2Migrator.V2_TYPE_MC;
+import static de.thm.arsnova.model.migration.FromV2Migrator.V2_TYPE_SCHOOL;
+import static de.thm.arsnova.model.migration.FromV2Migrator.V2_TYPE_VOTE;
+import static de.thm.arsnova.model.migration.FromV2Migrator.V2_TYPE_YESNO;
 
 import java.util.ArrayList;
 import java.util.LinkedHashMap;
@@ -30,7 +33,22 @@ import java.util.Map;
 import java.util.Optional;
 import java.util.stream.Collectors;
 
-import static de.thm.arsnova.model.migration.FromV2Migrator.*;
+import de.thm.arsnova.model.AnswerStatistics;
+import de.thm.arsnova.model.ChoiceQuestionContent;
+import de.thm.arsnova.model.RoomStatistics;
+import de.thm.arsnova.model.UserProfile;
+import de.thm.arsnova.model.migration.v2.Answer;
+import de.thm.arsnova.model.migration.v2.AnswerOption;
+import de.thm.arsnova.model.migration.v2.Comment;
+import de.thm.arsnova.model.migration.v2.Content;
+import de.thm.arsnova.model.migration.v2.Entity;
+import de.thm.arsnova.model.migration.v2.LoggedIn;
+import de.thm.arsnova.model.migration.v2.Motd;
+import de.thm.arsnova.model.migration.v2.MotdList;
+import de.thm.arsnova.model.migration.v2.Room;
+import de.thm.arsnova.model.migration.v2.RoomFeature;
+import de.thm.arsnova.model.migration.v2.RoomInfo;
+import de.thm.arsnova.model.migration.v2.VisitedRoom;
 
 /**
  * Converts entities from current model version to legacy version 2.
diff --git a/src/main/java/de/thm/arsnova/model/migration/v2/Answer.java b/src/main/java/de/thm/arsnova/model/migration/v2/Answer.java
index 2649e5b0d..31c1003f2 100644
--- a/src/main/java/de/thm/arsnova/model/migration/v2/Answer.java
+++ b/src/main/java/de/thm/arsnova/model/migration/v2/Answer.java
@@ -15,14 +15,16 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model.migration.v2;
 
 import com.fasterxml.jackson.annotation.JsonIgnore;
 import com.fasterxml.jackson.annotation.JsonView;
-import de.thm.arsnova.model.serialization.View;
 import io.swagger.annotations.ApiModel;
 import io.swagger.annotations.ApiModelProperty;
 
+import de.thm.arsnova.model.serialization.View;
+
 /**
  * Both a regular (single choice, evaluation, etc.) as well as a freetext answer.
  *
diff --git a/src/main/java/de/thm/arsnova/model/migration/v2/AnswerOption.java b/src/main/java/de/thm/arsnova/model/migration/v2/AnswerOption.java
index d9eae95f0..ea8f58885 100644
--- a/src/main/java/de/thm/arsnova/model/migration/v2/AnswerOption.java
+++ b/src/main/java/de/thm/arsnova/model/migration/v2/AnswerOption.java
@@ -15,15 +15,16 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model.migration.v2;
 
 import com.fasterxml.jackson.annotation.JsonView;
-import de.thm.arsnova.model.serialization.View;
 import io.swagger.annotations.ApiModel;
 import io.swagger.annotations.ApiModelProperty;
-
 import java.io.Serializable;
 
+import de.thm.arsnova.model.serialization.View;
+
 /**
  * Represents an Answer (Possible Answer) of Content.
  */
diff --git a/src/main/java/de/thm/arsnova/model/migration/v2/ClientAuthentication.java b/src/main/java/de/thm/arsnova/model/migration/v2/ClientAuthentication.java
index 357ab1091..7fb3b8a9c 100644
--- a/src/main/java/de/thm/arsnova/model/migration/v2/ClientAuthentication.java
+++ b/src/main/java/de/thm/arsnova/model/migration/v2/ClientAuthentication.java
@@ -15,17 +15,18 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model.migration.v2;
 
 import com.fasterxml.jackson.annotation.JsonView;
-import de.thm.arsnova.model.UserProfile;
-import de.thm.arsnova.model.serialization.View;
-import de.thm.arsnova.security.User;
+import java.io.Serializable;
+import java.util.Objects;
 import org.springframework.security.authentication.AnonymousAuthenticationToken;
 import org.springframework.security.core.Authentication;
 
-import java.io.Serializable;
-import java.util.Objects;
+import de.thm.arsnova.model.UserProfile;
+import de.thm.arsnova.model.serialization.View;
+import de.thm.arsnova.security.User;
 
 /**
  * Represents a user.
diff --git a/src/main/java/de/thm/arsnova/model/migration/v2/Comment.java b/src/main/java/de/thm/arsnova/model/migration/v2/Comment.java
index c0d77c4fe..057deaf3f 100644
--- a/src/main/java/de/thm/arsnova/model/migration/v2/Comment.java
+++ b/src/main/java/de/thm/arsnova/model/migration/v2/Comment.java
@@ -15,14 +15,16 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model.migration.v2;
 
 import com.fasterxml.jackson.annotation.JsonProperty;
 import com.fasterxml.jackson.annotation.JsonView;
-import de.thm.arsnova.model.serialization.View;
 import io.swagger.annotations.ApiModel;
 import io.swagger.annotations.ApiModelProperty;
 
+import de.thm.arsnova.model.serialization.View;
+
 /**
  * A Comment (Interposed/Feedback/Audience question) from a attendee in a Room.
  */
diff --git a/src/main/java/de/thm/arsnova/model/migration/v2/CommentReadingCount.java b/src/main/java/de/thm/arsnova/model/migration/v2/CommentReadingCount.java
index 7fe0f70bb..0a52b3bbe 100644
--- a/src/main/java/de/thm/arsnova/model/migration/v2/CommentReadingCount.java
+++ b/src/main/java/de/thm/arsnova/model/migration/v2/CommentReadingCount.java
@@ -15,13 +15,15 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model.migration.v2;
 
 import com.fasterxml.jackson.annotation.JsonView;
-import de.thm.arsnova.model.serialization.View;
 import io.swagger.annotations.ApiModel;
 import io.swagger.annotations.ApiModelProperty;
 
+import de.thm.arsnova.model.serialization.View;
+
 /**
  * Wrapper class for counting read and unread Comments for a Room or a single user.
  */
diff --git a/src/main/java/de/thm/arsnova/model/migration/v2/Content.java b/src/main/java/de/thm/arsnova/model/migration/v2/Content.java
index 6ea162654..24597bb43 100644
--- a/src/main/java/de/thm/arsnova/model/migration/v2/Content.java
+++ b/src/main/java/de/thm/arsnova/model/migration/v2/Content.java
@@ -15,17 +15,18 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model.migration.v2;
 
 import com.fasterxml.jackson.annotation.JsonView;
-import de.thm.arsnova.model.serialization.View;
 import io.swagger.annotations.ApiModel;
 import io.swagger.annotations.ApiModelProperty;
-
 import java.util.ArrayList;
 import java.util.Date;
 import java.util.List;
 
+import de.thm.arsnova.model.serialization.View;
+
 /**
  * Represents Content (Skill/Lecturer Question) in a Room.
  */
diff --git a/src/main/java/de/thm/arsnova/model/migration/v2/DbUser.java b/src/main/java/de/thm/arsnova/model/migration/v2/DbUser.java
index 18eb858a5..a54810bc9 100644
--- a/src/main/java/de/thm/arsnova/model/migration/v2/DbUser.java
+++ b/src/main/java/de/thm/arsnova/model/migration/v2/DbUser.java
@@ -15,9 +15,11 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model.migration.v2;
 
 import com.fasterxml.jackson.annotation.JsonView;
+
 import de.thm.arsnova.model.serialization.View;
 
 /**
diff --git a/src/main/java/de/thm/arsnova/model/migration/v2/Entity.java b/src/main/java/de/thm/arsnova/model/migration/v2/Entity.java
index c76a7c1dd..6fdb5df89 100644
--- a/src/main/java/de/thm/arsnova/model/migration/v2/Entity.java
+++ b/src/main/java/de/thm/arsnova/model/migration/v2/Entity.java
@@ -15,9 +15,11 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model.migration.v2;
 
 import com.fasterxml.jackson.annotation.JsonView;
+
 import de.thm.arsnova.model.serialization.View;
 
 public interface Entity {
diff --git a/src/main/java/de/thm/arsnova/model/migration/v2/LogEntry.java b/src/main/java/de/thm/arsnova/model/migration/v2/LogEntry.java
index 8921c754f..522c3928c 100644
--- a/src/main/java/de/thm/arsnova/model/migration/v2/LogEntry.java
+++ b/src/main/java/de/thm/arsnova/model/migration/v2/LogEntry.java
@@ -15,14 +15,15 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model.migration.v2;
 
 import com.fasterxml.jackson.annotation.JsonProperty;
 import com.fasterxml.jackson.annotation.JsonView;
-import de.thm.arsnova.model.serialization.View;
-
 import java.util.Map;
 
+import de.thm.arsnova.model.serialization.View;
+
 public class LogEntry implements Entity {
 	public enum LogLevel {
 		TRACE,
diff --git a/src/main/java/de/thm/arsnova/model/migration/v2/LoggedIn.java b/src/main/java/de/thm/arsnova/model/migration/v2/LoggedIn.java
index 0aa2ccab7..a34ebc862 100644
--- a/src/main/java/de/thm/arsnova/model/migration/v2/LoggedIn.java
+++ b/src/main/java/de/thm/arsnova/model/migration/v2/LoggedIn.java
@@ -15,15 +15,16 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model.migration.v2;
 
 import com.fasterxml.jackson.annotation.JsonView;
-import de.thm.arsnova.model.serialization.View;
 import io.swagger.annotations.ApiModel;
-
 import java.util.ArrayList;
 import java.util.List;
 
+import de.thm.arsnova.model.serialization.View;
+
 /**
  * Once a user joins a session, this class is used to identify a returning user.
  */
diff --git a/src/main/java/de/thm/arsnova/model/migration/v2/Motd.java b/src/main/java/de/thm/arsnova/model/migration/v2/Motd.java
index d1db64876..68bb3f51a 100644
--- a/src/main/java/de/thm/arsnova/model/migration/v2/Motd.java
+++ b/src/main/java/de/thm/arsnova/model/migration/v2/Motd.java
@@ -15,15 +15,16 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model.migration.v2;
 
 import com.fasterxml.jackson.annotation.JsonView;
-import de.thm.arsnova.model.serialization.View;
 import io.swagger.annotations.ApiModel;
 import io.swagger.annotations.ApiModelProperty;
-
 import java.util.Date;
 
+import de.thm.arsnova.model.serialization.View;
+
 /**
  * Represents a Message of the Day.
  */
diff --git a/src/main/java/de/thm/arsnova/model/migration/v2/MotdList.java b/src/main/java/de/thm/arsnova/model/migration/v2/MotdList.java
index 6240b50a7..27ba44b0c 100644
--- a/src/main/java/de/thm/arsnova/model/migration/v2/MotdList.java
+++ b/src/main/java/de/thm/arsnova/model/migration/v2/MotdList.java
@@ -15,13 +15,15 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model.migration.v2;
 
 import com.fasterxml.jackson.annotation.JsonView;
-import de.thm.arsnova.model.serialization.View;
 import io.swagger.annotations.ApiModel;
 import io.swagger.annotations.ApiModelProperty;
 
+import de.thm.arsnova.model.serialization.View;
+
 /**
  * Contains a list of MotD IDs a user has acknowledged.
  */
diff --git a/src/main/java/de/thm/arsnova/model/migration/v2/Room.java b/src/main/java/de/thm/arsnova/model/migration/v2/Room.java
index aa32d619c..489043a62 100644
--- a/src/main/java/de/thm/arsnova/model/migration/v2/Room.java
+++ b/src/main/java/de/thm/arsnova/model/migration/v2/Room.java
@@ -15,15 +15,17 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model.migration.v2;
 
 import com.fasterxml.jackson.annotation.JsonIgnore;
 import com.fasterxml.jackson.annotation.JsonView;
-import de.thm.arsnova.model.ScoreOptions;
-import de.thm.arsnova.model.serialization.View;
 import io.swagger.annotations.ApiModel;
 import io.swagger.annotations.ApiModelProperty;
 
+import de.thm.arsnova.model.ScoreOptions;
+import de.thm.arsnova.model.serialization.View;
+
 /**
  * Represents a Room (Session).
  */
diff --git a/src/main/java/de/thm/arsnova/model/migration/v2/RoomFeature.java b/src/main/java/de/thm/arsnova/model/migration/v2/RoomFeature.java
index e7786c3fb..2d377a2c8 100644
--- a/src/main/java/de/thm/arsnova/model/migration/v2/RoomFeature.java
+++ b/src/main/java/de/thm/arsnova/model/migration/v2/RoomFeature.java
@@ -15,15 +15,16 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model.migration.v2;
 
 import com.fasterxml.jackson.annotation.JsonView;
-import de.thm.arsnova.model.serialization.View;
 import io.swagger.annotations.ApiModel;
 import io.swagger.annotations.ApiModelProperty;
-
 import java.io.Serializable;
 
+import de.thm.arsnova.model.serialization.View;
+
 /**
  * Contains fields that describe which specific Feature is activated for a Room.
  */
diff --git a/src/main/java/de/thm/arsnova/model/migration/v2/RoomInfo.java b/src/main/java/de/thm/arsnova/model/migration/v2/RoomInfo.java
index 528392b4d..0633186d0 100644
--- a/src/main/java/de/thm/arsnova/model/migration/v2/RoomInfo.java
+++ b/src/main/java/de/thm/arsnova/model/migration/v2/RoomInfo.java
@@ -15,16 +15,17 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model.migration.v2;
 
 import com.fasterxml.jackson.annotation.JsonView;
-import de.thm.arsnova.model.serialization.View;
 import io.swagger.annotations.ApiModel;
 import io.swagger.annotations.ApiModelProperty;
-
 import java.util.ArrayList;
 import java.util.List;
 
+import de.thm.arsnova.model.serialization.View;
+
 /**
  * Summary information of a specific Room. For example, this is used to display list entries of a user's Rooms as well
  * as a user's Room History (Visited Rooms).
diff --git a/src/main/java/de/thm/arsnova/model/migration/v2/VisitedRoom.java b/src/main/java/de/thm/arsnova/model/migration/v2/VisitedRoom.java
index 9a21125db..aaed1ad9f 100644
--- a/src/main/java/de/thm/arsnova/model/migration/v2/VisitedRoom.java
+++ b/src/main/java/de/thm/arsnova/model/migration/v2/VisitedRoom.java
@@ -15,13 +15,15 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model.migration.v2;
 
 import com.fasterxml.jackson.annotation.JsonProperty;
 import com.fasterxml.jackson.annotation.JsonView;
-import de.thm.arsnova.model.serialization.View;
 import io.swagger.annotations.ApiModel;
 
+import de.thm.arsnova.model.serialization.View;
+
 /**
  * A Room (Session) a user has visited previously.
  */
diff --git a/src/main/java/de/thm/arsnova/model/package-info.java b/src/main/java/de/thm/arsnova/model/package-info.java
index 91ada1f83..f7971e9b6 100644
--- a/src/main/java/de/thm/arsnova/model/package-info.java
+++ b/src/main/java/de/thm/arsnova/model/package-info.java
@@ -1,4 +1,5 @@
 /**
  * Classes to translate objects to and from JSON
  */
+
 package de.thm.arsnova.model;
diff --git a/src/main/java/de/thm/arsnova/model/serialization/CouchDbDocumentMixIn.java b/src/main/java/de/thm/arsnova/model/serialization/CouchDbDocumentMixIn.java
index c6bd96d08..554bf1103 100644
--- a/src/main/java/de/thm/arsnova/model/serialization/CouchDbDocumentMixIn.java
+++ b/src/main/java/de/thm/arsnova/model/serialization/CouchDbDocumentMixIn.java
@@ -15,12 +15,14 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model.serialization;
 
 import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
 import com.fasterxml.jackson.annotation.JsonInclude;
 import com.fasterxml.jackson.annotation.JsonProperty;
 import com.fasterxml.jackson.databind.annotation.JsonSerialize;
+
 import de.thm.arsnova.model.Entity;
 
 @JsonIgnoreProperties(value = {"type"}, allowGetters = true)
diff --git a/src/main/java/de/thm/arsnova/model/serialization/CouchDbDocumentModule.java b/src/main/java/de/thm/arsnova/model/serialization/CouchDbDocumentModule.java
index 06a0b5475..546365644 100644
--- a/src/main/java/de/thm/arsnova/model/serialization/CouchDbDocumentModule.java
+++ b/src/main/java/de/thm/arsnova/model/serialization/CouchDbDocumentModule.java
@@ -15,9 +15,11 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model.serialization;
 
 import com.fasterxml.jackson.databind.module.SimpleModule;
+
 import de.thm.arsnova.model.Entity;
 
 public class CouchDbDocumentModule extends SimpleModule {
diff --git a/src/main/java/de/thm/arsnova/model/serialization/CouchDbDocumentV2MixIn.java b/src/main/java/de/thm/arsnova/model/serialization/CouchDbDocumentV2MixIn.java
index 4e06a77e6..7c962a834 100644
--- a/src/main/java/de/thm/arsnova/model/serialization/CouchDbDocumentV2MixIn.java
+++ b/src/main/java/de/thm/arsnova/model/serialization/CouchDbDocumentV2MixIn.java
@@ -15,12 +15,14 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model.serialization;
 
 import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
 import com.fasterxml.jackson.annotation.JsonInclude;
 import com.fasterxml.jackson.annotation.JsonProperty;
 import com.fasterxml.jackson.databind.annotation.JsonSerialize;
+
 import de.thm.arsnova.model.Entity;
 
 @JsonIgnoreProperties(value = {"type"}, allowGetters = true)
diff --git a/src/main/java/de/thm/arsnova/model/serialization/CouchDbObjectMapperFactory.java b/src/main/java/de/thm/arsnova/model/serialization/CouchDbObjectMapperFactory.java
index be2518bb4..b53860bf6 100644
--- a/src/main/java/de/thm/arsnova/model/serialization/CouchDbObjectMapperFactory.java
+++ b/src/main/java/de/thm/arsnova/model/serialization/CouchDbObjectMapperFactory.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model.serialization;
 
 import com.fasterxml.jackson.databind.MapperFeature;
diff --git a/src/main/java/de/thm/arsnova/model/serialization/CouchDbTypeFieldConverter.java b/src/main/java/de/thm/arsnova/model/serialization/CouchDbTypeFieldConverter.java
index 76a30a25c..8f1b3293f 100644
--- a/src/main/java/de/thm/arsnova/model/serialization/CouchDbTypeFieldConverter.java
+++ b/src/main/java/de/thm/arsnova/model/serialization/CouchDbTypeFieldConverter.java
@@ -15,11 +15,13 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model.serialization;
 
 import com.fasterxml.jackson.databind.JavaType;
 import com.fasterxml.jackson.databind.type.TypeFactory;
 import com.fasterxml.jackson.databind.util.Converter;
+
 import de.thm.arsnova.model.Entity;
 
 public class CouchDbTypeFieldConverter implements Converter<Class<? extends Entity>, String> {
diff --git a/src/main/java/de/thm/arsnova/model/serialization/CouchDbTypeFieldV2Converter.java b/src/main/java/de/thm/arsnova/model/serialization/CouchDbTypeFieldV2Converter.java
index 41ee2c099..1744a8727 100644
--- a/src/main/java/de/thm/arsnova/model/serialization/CouchDbTypeFieldV2Converter.java
+++ b/src/main/java/de/thm/arsnova/model/serialization/CouchDbTypeFieldV2Converter.java
@@ -15,11 +15,15 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model.serialization;
 
 import com.fasterxml.jackson.databind.JavaType;
 import com.fasterxml.jackson.databind.type.TypeFactory;
 import com.fasterxml.jackson.databind.util.Converter;
+import java.util.HashMap;
+import java.util.Map;
+
 import de.thm.arsnova.model.migration.v2.Answer;
 import de.thm.arsnova.model.migration.v2.Comment;
 import de.thm.arsnova.model.migration.v2.Content;
@@ -30,9 +34,6 @@ import de.thm.arsnova.model.migration.v2.Motd;
 import de.thm.arsnova.model.migration.v2.MotdList;
 import de.thm.arsnova.model.migration.v2.Room;
 
-import java.util.HashMap;
-import java.util.Map;
-
 public class CouchDbTypeFieldV2Converter implements Converter<Class<? extends Entity>, String> {
 	private static final Map<Class<? extends Entity>, String> typeMapping = new HashMap<>();
 
diff --git a/src/main/java/de/thm/arsnova/model/serialization/FormatAnswerTypeIdResolver.java b/src/main/java/de/thm/arsnova/model/serialization/FormatAnswerTypeIdResolver.java
index 903d9ca97..a415be14a 100644
--- a/src/main/java/de/thm/arsnova/model/serialization/FormatAnswerTypeIdResolver.java
+++ b/src/main/java/de/thm/arsnova/model/serialization/FormatAnswerTypeIdResolver.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model.serialization;
 
 import com.fasterxml.jackson.annotation.JsonTypeInfo;
@@ -22,13 +23,13 @@ import com.fasterxml.jackson.databind.DatabindContext;
 import com.fasterxml.jackson.databind.JavaType;
 import com.fasterxml.jackson.databind.jsontype.impl.TypeIdResolverBase;
 import com.fasterxml.jackson.databind.type.TypeFactory;
+import java.io.IOException;
+
 import de.thm.arsnova.model.Answer;
 import de.thm.arsnova.model.ChoiceAnswer;
 import de.thm.arsnova.model.Content;
 import de.thm.arsnova.model.TextAnswer;
 
-import java.io.IOException;
-
 public class FormatAnswerTypeIdResolver extends TypeIdResolverBase {
 	@Override
 	public String idFromValue(final Object value) {
diff --git a/src/main/java/de/thm/arsnova/model/serialization/FormatContentTypeIdResolver.java b/src/main/java/de/thm/arsnova/model/serialization/FormatContentTypeIdResolver.java
index 431e17898..d52dc1f66 100644
--- a/src/main/java/de/thm/arsnova/model/serialization/FormatContentTypeIdResolver.java
+++ b/src/main/java/de/thm/arsnova/model/serialization/FormatContentTypeIdResolver.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model.serialization;
 
 import com.fasterxml.jackson.annotation.JsonTypeInfo;
@@ -22,11 +23,11 @@ import com.fasterxml.jackson.databind.DatabindContext;
 import com.fasterxml.jackson.databind.JavaType;
 import com.fasterxml.jackson.databind.jsontype.impl.TypeIdResolverBase;
 import com.fasterxml.jackson.databind.type.TypeFactory;
+import java.io.IOException;
+
 import de.thm.arsnova.model.ChoiceQuestionContent;
 import de.thm.arsnova.model.Content;
 
-import java.io.IOException;
-
 public class FormatContentTypeIdResolver extends TypeIdResolverBase {
 	@Override
 	public String idFromValue(final Object value) {
diff --git a/src/main/java/de/thm/arsnova/model/serialization/View.java b/src/main/java/de/thm/arsnova/model/serialization/View.java
index b97ab7860..93637926c 100644
--- a/src/main/java/de/thm/arsnova/model/serialization/View.java
+++ b/src/main/java/de/thm/arsnova/model/serialization/View.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model.serialization;
 
 public class View {
diff --git a/src/main/java/de/thm/arsnova/model/transport/ImportExportContainer.java b/src/main/java/de/thm/arsnova/model/transport/ImportExportContainer.java
index 9cfbee398..eb4bf7530 100644
--- a/src/main/java/de/thm/arsnova/model/transport/ImportExportContainer.java
+++ b/src/main/java/de/thm/arsnova/model/transport/ImportExportContainer.java
@@ -15,9 +15,16 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model.transport;
 
 import com.fasterxml.jackson.annotation.JsonView;
+import io.swagger.annotations.ApiModel;
+import io.swagger.annotations.ApiModelProperty;
+import java.util.ArrayList;
+import java.util.Date;
+import java.util.List;
+
 import de.thm.arsnova.model.migration.v2.Answer;
 import de.thm.arsnova.model.migration.v2.ClientAuthentication;
 import de.thm.arsnova.model.migration.v2.Comment;
@@ -27,12 +34,6 @@ import de.thm.arsnova.model.migration.v2.Room;
 import de.thm.arsnova.model.migration.v2.RoomFeature;
 import de.thm.arsnova.model.migration.v2.RoomInfo;
 import de.thm.arsnova.model.serialization.View;
-import io.swagger.annotations.ApiModel;
-import io.swagger.annotations.ApiModelProperty;
-
-import java.util.ArrayList;
-import java.util.Date;
-import java.util.List;
 
 /**
  * This class is used to allow the import and export of a session.
diff --git a/src/main/java/de/thm/arsnova/model/transport/ScoreStatistics.java b/src/main/java/de/thm/arsnova/model/transport/ScoreStatistics.java
index ad042f23e..63dc193d5 100644
--- a/src/main/java/de/thm/arsnova/model/transport/ScoreStatistics.java
+++ b/src/main/java/de/thm/arsnova/model/transport/ScoreStatistics.java
@@ -15,13 +15,15 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model.transport;
 
 import com.fasterxml.jackson.annotation.JsonView;
-import de.thm.arsnova.model.serialization.View;
 import io.swagger.annotations.ApiModel;
 import io.swagger.annotations.ApiModelProperty;
 
+import de.thm.arsnova.model.serialization.View;
+
 /**
  * The calculated score along with meta-data.
  */
diff --git a/src/main/java/de/thm/arsnova/model/transport/package-info.java b/src/main/java/de/thm/arsnova/model/transport/package-info.java
index 39062cacc..c23f58518 100644
--- a/src/main/java/de/thm/arsnova/model/transport/package-info.java
+++ b/src/main/java/de/thm/arsnova/model/transport/package-info.java
@@ -4,4 +4,5 @@
  * Since sometimes only a subset of properties are needed, sending the whole entity is a waste of bandwith. Therefore,
  * entities optimized for data transport are located here.
  */
+
 package de.thm.arsnova.model.transport;
diff --git a/src/main/java/de/thm/arsnova/package-info.java b/src/main/java/de/thm/arsnova/package-info.java
index b0aeba268..e961b44b2 100644
--- a/src/main/java/de/thm/arsnova/package-info.java
+++ b/src/main/java/de/thm/arsnova/package-info.java
@@ -1,4 +1,5 @@
 /**
  * Miscellaneous classes and interfaces that do not fit in any of the given sub-packages
  */
+
 package de.thm.arsnova;
diff --git a/src/main/java/de/thm/arsnova/persistence/AnswerRepository.java b/src/main/java/de/thm/arsnova/persistence/AnswerRepository.java
index 97f60c10d..11a664b28 100644
--- a/src/main/java/de/thm/arsnova/persistence/AnswerRepository.java
+++ b/src/main/java/de/thm/arsnova/persistence/AnswerRepository.java
@@ -15,13 +15,14 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.persistence;
 
+import java.util.List;
+
 import de.thm.arsnova.model.Answer;
 import de.thm.arsnova.model.AnswerStatistics;
 
-import java.util.List;
-
 public interface AnswerRepository extends CrudRepository<Answer, String> {
 	<T extends Answer> T findByContentIdUserIdPiRound(String contentId, Class<T> type, String userId, int piRound);
 	AnswerStatistics findByContentIdRound(String contentId, int round, final int optionCount);
diff --git a/src/main/java/de/thm/arsnova/persistence/CommentRepository.java b/src/main/java/de/thm/arsnova/persistence/CommentRepository.java
index d8735a96a..9fe9cf336 100644
--- a/src/main/java/de/thm/arsnova/persistence/CommentRepository.java
+++ b/src/main/java/de/thm/arsnova/persistence/CommentRepository.java
@@ -1,10 +1,10 @@
 package de.thm.arsnova.persistence;
 
+import java.util.List;
+
 import de.thm.arsnova.model.Comment;
 import de.thm.arsnova.model.migration.v2.CommentReadingCount;
 
-import java.util.List;
-
 public interface CommentRepository extends CrudRepository<Comment, String> {
 	int countByRoomId(String roomId);
 	CommentReadingCount countReadingByRoomId(String roomId);
diff --git a/src/main/java/de/thm/arsnova/persistence/ContentRepository.java b/src/main/java/de/thm/arsnova/persistence/ContentRepository.java
index 098eef74d..8bda32a10 100644
--- a/src/main/java/de/thm/arsnova/persistence/ContentRepository.java
+++ b/src/main/java/de/thm/arsnova/persistence/ContentRepository.java
@@ -1,9 +1,9 @@
 package de.thm.arsnova.persistence;
 
-import de.thm.arsnova.model.Content;
-
 import java.util.List;
 
+import de.thm.arsnova.model.Content;
+
 public interface ContentRepository extends CrudRepository<Content, String> {
 	List<Content> findByRoomIdAndVariantAndActive(Object... keys);
 	List<Content> findByRoomIdForUsers(String roomId);
diff --git a/src/main/java/de/thm/arsnova/persistence/CrudRepository.java b/src/main/java/de/thm/arsnova/persistence/CrudRepository.java
index 6553b84a9..ba71213bb 100644
--- a/src/main/java/de/thm/arsnova/persistence/CrudRepository.java
+++ b/src/main/java/de/thm/arsnova/persistence/CrudRepository.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.persistence;
 
 /**
diff --git a/src/main/java/de/thm/arsnova/persistence/LogEntryRepository.java b/src/main/java/de/thm/arsnova/persistence/LogEntryRepository.java
index a788c01bf..368211ba9 100644
--- a/src/main/java/de/thm/arsnova/persistence/LogEntryRepository.java
+++ b/src/main/java/de/thm/arsnova/persistence/LogEntryRepository.java
@@ -15,13 +15,14 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-package de.thm.arsnova.persistence;
 
-import de.thm.arsnova.model.migration.v2.LogEntry;
+package de.thm.arsnova.persistence;
 
 import java.util.HashMap;
 import java.util.Map;
 
+import de.thm.arsnova.model.migration.v2.LogEntry;
+
 public interface LogEntryRepository {
 	/**
 	 * Logs an event to the database. Arbitrary data can be attached as payload. Database logging should only be used
diff --git a/src/main/java/de/thm/arsnova/persistence/MotdRepository.java b/src/main/java/de/thm/arsnova/persistence/MotdRepository.java
index e00a88cd8..93dbca61d 100644
--- a/src/main/java/de/thm/arsnova/persistence/MotdRepository.java
+++ b/src/main/java/de/thm/arsnova/persistence/MotdRepository.java
@@ -15,12 +15,13 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-package de.thm.arsnova.persistence;
 
-import de.thm.arsnova.model.Motd;
+package de.thm.arsnova.persistence;
 
 import java.util.List;
 
+import de.thm.arsnova.model.Motd;
+
 public interface MotdRepository extends CrudRepository<Motd, String> {
 	List<Motd> findGlobalForAdmin();
 	List<Motd> findGlobalForAll();
diff --git a/src/main/java/de/thm/arsnova/persistence/RoomRepository.java b/src/main/java/de/thm/arsnova/persistence/RoomRepository.java
index d2954c1dd..829f7877e 100644
--- a/src/main/java/de/thm/arsnova/persistence/RoomRepository.java
+++ b/src/main/java/de/thm/arsnova/persistence/RoomRepository.java
@@ -15,15 +15,16 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.persistence;
 
+import java.util.List;
+
 import de.thm.arsnova.connector.model.Course;
 import de.thm.arsnova.model.Room;
 import de.thm.arsnova.model.migration.v2.ClientAuthentication;
 import de.thm.arsnova.model.transport.ImportExportContainer;
 
-import java.util.List;
-
 public interface RoomRepository extends CrudRepository<Room, String> {
 	Room findByShortId(String shortId);
 	List<Room> findInactiveGuestRoomsMetadata(long lastActivityBefore);
diff --git a/src/main/java/de/thm/arsnova/persistence/SessionStatisticsRepository.java b/src/main/java/de/thm/arsnova/persistence/SessionStatisticsRepository.java
index 0e407aaf9..1050c4fbc 100644
--- a/src/main/java/de/thm/arsnova/persistence/SessionStatisticsRepository.java
+++ b/src/main/java/de/thm/arsnova/persistence/SessionStatisticsRepository.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.persistence;
 
 import de.thm.arsnova.model.Room;
diff --git a/src/main/java/de/thm/arsnova/persistence/StatisticsRepository.java b/src/main/java/de/thm/arsnova/persistence/StatisticsRepository.java
index 015eff7de..388fecdd9 100644
--- a/src/main/java/de/thm/arsnova/persistence/StatisticsRepository.java
+++ b/src/main/java/de/thm/arsnova/persistence/StatisticsRepository.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.persistence;
 
 import de.thm.arsnova.model.Statistics;
diff --git a/src/main/java/de/thm/arsnova/persistence/UserRepository.java b/src/main/java/de/thm/arsnova/persistence/UserRepository.java
index 7abcd9e67..c9db248c5 100644
--- a/src/main/java/de/thm/arsnova/persistence/UserRepository.java
+++ b/src/main/java/de/thm/arsnova/persistence/UserRepository.java
@@ -15,12 +15,13 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-package de.thm.arsnova.persistence;
 
-import de.thm.arsnova.model.UserProfile;
+package de.thm.arsnova.persistence;
 
 import java.util.List;
 
+import de.thm.arsnova.model.UserProfile;
+
 public interface UserRepository extends CrudRepository<UserProfile, String> {
 	UserProfile findByAuthProviderAndLoginId(UserProfile.AuthProvider authProvider, String loginId);
 	List<UserProfile> findByLoginId(String loginId);
diff --git a/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbAnswerRepository.java b/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbAnswerRepository.java
index 528c13c09..eb22d7bcc 100644
--- a/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbAnswerRepository.java
+++ b/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbAnswerRepository.java
@@ -15,13 +15,16 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.persistence.couchdb;
 
 import com.fasterxml.jackson.databind.JsonNode;
-import de.thm.arsnova.model.Answer;
-import de.thm.arsnova.model.AnswerStatistics;
-import de.thm.arsnova.persistence.AnswerRepository;
-import de.thm.arsnova.persistence.LogEntryRepository;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
 import org.ektorp.ComplexKey;
 import org.ektorp.CouchDbConnector;
 import org.ektorp.ViewResult;
@@ -31,12 +34,10 @@ import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.context.ApplicationEventPublisher;
 import org.springframework.context.ApplicationEventPublisherAware;
 
-import java.util.ArrayList;
-import java.util.Arrays;
-import java.util.Collections;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
+import de.thm.arsnova.model.Answer;
+import de.thm.arsnova.model.AnswerStatistics;
+import de.thm.arsnova.persistence.AnswerRepository;
+import de.thm.arsnova.persistence.LogEntryRepository;
 
 public class CouchDbAnswerRepository extends CouchDbCrudRepository<Answer> implements AnswerRepository, ApplicationEventPublisherAware {
 	private static final Logger logger = LoggerFactory.getLogger(CouchDbAnswerRepository.class);
diff --git a/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbAttachmentRepository.java b/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbAttachmentRepository.java
index 5bc66743e..7ec663059 100644
--- a/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbAttachmentRepository.java
+++ b/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbAttachmentRepository.java
@@ -15,11 +15,13 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.persistence.couchdb;
 
+import org.ektorp.CouchDbConnector;
+
 import de.thm.arsnova.model.Attachment;
 import de.thm.arsnova.persistence.AttachmentRepository;
-import org.ektorp.CouchDbConnector;
 
 public class CouchDbAttachmentRepository extends CouchDbCrudRepository<Attachment> implements AttachmentRepository {
 	public CouchDbAttachmentRepository(final CouchDbConnector db, final boolean createIfNotExists) {
diff --git a/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbCommentRepository.java b/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbCommentRepository.java
index 2f3202d55..aa4a44f81 100644
--- a/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbCommentRepository.java
+++ b/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbCommentRepository.java
@@ -15,13 +15,11 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.persistence.couchdb;
 
 import com.fasterxml.jackson.databind.JsonNode;
-import de.thm.arsnova.model.Comment;
-import de.thm.arsnova.model.migration.v2.CommentReadingCount;
-import de.thm.arsnova.persistence.CommentRepository;
-import de.thm.arsnova.persistence.LogEntryRepository;
+import java.util.List;
 import org.ektorp.ComplexKey;
 import org.ektorp.CouchDbConnector;
 import org.ektorp.ViewResult;
@@ -29,7 +27,10 @@ import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.beans.factory.annotation.Autowired;
 
-import java.util.List;
+import de.thm.arsnova.model.Comment;
+import de.thm.arsnova.model.migration.v2.CommentReadingCount;
+import de.thm.arsnova.persistence.CommentRepository;
+import de.thm.arsnova.persistence.LogEntryRepository;
 
 public class CouchDbCommentRepository extends CouchDbCrudRepository<Comment> implements CommentRepository {
 	private static final Logger logger = LoggerFactory.getLogger(CouchDbCommentRepository.class);
diff --git a/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbContentRepository.java b/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbContentRepository.java
index 4e8e9298f..30f657fdf 100644
--- a/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbContentRepository.java
+++ b/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbContentRepository.java
@@ -15,17 +15,8 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-package de.thm.arsnova.persistence.couchdb;
 
-import de.thm.arsnova.model.Content;
-import de.thm.arsnova.persistence.ContentRepository;
-import de.thm.arsnova.persistence.LogEntryRepository;
-import org.ektorp.ComplexKey;
-import org.ektorp.CouchDbConnector;
-import org.ektorp.ViewResult;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-import org.springframework.beans.factory.annotation.Autowired;
+package de.thm.arsnova.persistence.couchdb;
 
 import java.util.ArrayList;
 import java.util.Arrays;
@@ -34,6 +25,16 @@ import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
+import org.ektorp.ComplexKey;
+import org.ektorp.CouchDbConnector;
+import org.ektorp.ViewResult;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.annotation.Autowired;
+
+import de.thm.arsnova.model.Content;
+import de.thm.arsnova.persistence.ContentRepository;
+import de.thm.arsnova.persistence.LogEntryRepository;
 
 public class CouchDbContentRepository extends CouchDbCrudRepository<Content> implements ContentRepository {
 	private static final Logger logger = LoggerFactory.getLogger(CouchDbContentRepository.class);
diff --git a/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbCrudRepository.java b/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbCrudRepository.java
index 1d1bee41b..b468703b3 100644
--- a/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbCrudRepository.java
+++ b/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbCrudRepository.java
@@ -15,15 +15,8 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-package de.thm.arsnova.persistence.couchdb;
 
-import de.thm.arsnova.model.Entity;
-import de.thm.arsnova.persistence.CrudRepository;
-import org.ektorp.BulkDeleteDocument;
-import org.ektorp.CouchDbConnector;
-import org.ektorp.ViewResult;
-import org.ektorp.support.CouchDbRepositorySupport;
-import org.springframework.data.repository.NoRepositoryBean;
+package de.thm.arsnova.persistence.couchdb;
 
 import java.util.Collection;
 import java.util.Collections;
@@ -31,6 +24,14 @@ import java.util.List;
 import java.util.Optional;
 import java.util.function.BiConsumer;
 import java.util.stream.Collectors;
+import org.ektorp.BulkDeleteDocument;
+import org.ektorp.CouchDbConnector;
+import org.ektorp.ViewResult;
+import org.ektorp.support.CouchDbRepositorySupport;
+import org.springframework.data.repository.NoRepositoryBean;
+
+import de.thm.arsnova.model.Entity;
+import de.thm.arsnova.persistence.CrudRepository;
 
 @NoRepositoryBean
 abstract class CouchDbCrudRepository<T extends Entity> extends CouchDbRepositorySupport<T> implements CrudRepository<T, String> {
diff --git a/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbInitializer.java b/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbInitializer.java
index 4da1e17f5..0e5f7c168 100644
--- a/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbInitializer.java
+++ b/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbInitializer.java
@@ -15,13 +15,23 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.persistence.couchdb;
 
 import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.ObjectMapper;
-import de.thm.arsnova.model.MigrationState;
-import de.thm.arsnova.persistence.couchdb.migrations.MigrationExecutor;
-import de.thm.arsnova.service.StatusService;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.stream.Collectors;
+import javax.annotation.PostConstruct;
+import javax.script.Bindings;
+import javax.script.ScriptEngine;
+import javax.script.ScriptEngineManager;
+import javax.script.ScriptException;
 import org.ektorp.CouchDbConnector;
 import org.ektorp.DbAccessException;
 import org.ektorp.DocumentNotFoundException;
@@ -39,18 +49,9 @@ import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
 import org.springframework.stereotype.Component;
 import org.springframework.util.FileCopyUtils;
 
-import javax.annotation.PostConstruct;
-import javax.script.Bindings;
-import javax.script.ScriptEngine;
-import javax.script.ScriptEngineManager;
-import javax.script.ScriptException;
-import java.io.IOException;
-import java.io.InputStreamReader;
-import java.util.ArrayList;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
-import java.util.stream.Collectors;
+import de.thm.arsnova.model.MigrationState;
+import de.thm.arsnova.persistence.couchdb.migrations.MigrationExecutor;
+import de.thm.arsnova.service.StatusService;
 
 @Component
 public class CouchDbInitializer implements ResourceLoaderAware {
diff --git a/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbLogEntryRepository.java b/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbLogEntryRepository.java
index 0c7b4fbe3..84d164bc4 100644
--- a/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbLogEntryRepository.java
+++ b/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbLogEntryRepository.java
@@ -15,16 +15,17 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.persistence.couchdb;
 
-import de.thm.arsnova.model.migration.v2.LogEntry;
-import de.thm.arsnova.persistence.LogEntryRepository;
+import java.util.Map;
 import org.ektorp.CouchDbConnector;
 import org.ektorp.support.CouchDbRepositorySupport;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import java.util.Map;
+import de.thm.arsnova.model.migration.v2.LogEntry;
+import de.thm.arsnova.persistence.LogEntryRepository;
 
 public class CouchDbLogEntryRepository extends CouchDbRepositorySupport<LogEntry> implements LogEntryRepository {
 	private static final Logger logger = LoggerFactory.getLogger(CouchDbLogEntryRepository.class);
diff --git a/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbMotdRepository.java b/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbMotdRepository.java
index c39e96a69..7ede4c5ac 100644
--- a/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbMotdRepository.java
+++ b/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbMotdRepository.java
@@ -15,16 +15,17 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.persistence.couchdb;
 
-import de.thm.arsnova.model.Motd;
-import de.thm.arsnova.persistence.MotdRepository;
+import java.util.ArrayList;
+import java.util.List;
 import org.ektorp.CouchDbConnector;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import java.util.ArrayList;
-import java.util.List;
+import de.thm.arsnova.model.Motd;
+import de.thm.arsnova.persistence.MotdRepository;
 
 public class CouchDbMotdRepository extends CouchDbCrudRepository<Motd> implements MotdRepository {
 	private static final Logger logger = LoggerFactory.getLogger(CouchDbMotdRepository.class);
diff --git a/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbRoomRepository.java b/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbRoomRepository.java
index 4ac435f1c..95ab3a69b 100644
--- a/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbRoomRepository.java
+++ b/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbRoomRepository.java
@@ -15,23 +15,8 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-package de.thm.arsnova.persistence.couchdb;
 
-import de.thm.arsnova.connector.model.Course;
-import de.thm.arsnova.model.Room;
-import de.thm.arsnova.model.RoomStatistics;
-import de.thm.arsnova.model.migration.v2.ClientAuthentication;
-import de.thm.arsnova.model.transport.ImportExportContainer;
-import de.thm.arsnova.persistence.LogEntryRepository;
-import de.thm.arsnova.persistence.MotdRepository;
-import de.thm.arsnova.persistence.RoomRepository;
-import org.ektorp.ComplexKey;
-import org.ektorp.CouchDbConnector;
-import org.ektorp.ViewQuery;
-import org.ektorp.ViewResult;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-import org.springframework.beans.factory.annotation.Autowired;
+package de.thm.arsnova.persistence.couchdb;
 
 import java.io.IOException;
 import java.util.AbstractMap;
@@ -42,6 +27,22 @@ import java.util.List;
 import java.util.Map;
 import java.util.Set;
 import java.util.stream.Collectors;
+import org.ektorp.ComplexKey;
+import org.ektorp.CouchDbConnector;
+import org.ektorp.ViewQuery;
+import org.ektorp.ViewResult;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.annotation.Autowired;
+
+import de.thm.arsnova.connector.model.Course;
+import de.thm.arsnova.model.Room;
+import de.thm.arsnova.model.RoomStatistics;
+import de.thm.arsnova.model.migration.v2.ClientAuthentication;
+import de.thm.arsnova.model.transport.ImportExportContainer;
+import de.thm.arsnova.persistence.LogEntryRepository;
+import de.thm.arsnova.persistence.MotdRepository;
+import de.thm.arsnova.persistence.RoomRepository;
 
 public class CouchDbRoomRepository extends CouchDbCrudRepository<Room> implements RoomRepository {
 	private static final Logger logger = LoggerFactory.getLogger(CouchDbRoomRepository.class);
diff --git a/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbSessionStatisticsRepository.java b/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbSessionStatisticsRepository.java
index 98edfb769..431dafe15 100644
--- a/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbSessionStatisticsRepository.java
+++ b/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbSessionStatisticsRepository.java
@@ -15,17 +15,19 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.persistence.couchdb;
 
 import com.fasterxml.jackson.databind.JsonNode;
-import de.thm.arsnova.model.Room;
-import de.thm.arsnova.persistence.SessionStatisticsRepository;
-import de.thm.arsnova.service.score.Score;
 import org.ektorp.ComplexKey;
 import org.ektorp.CouchDbConnector;
 import org.ektorp.ViewResult;
 import org.ektorp.support.CouchDbRepositorySupport;
 
+import de.thm.arsnova.model.Room;
+import de.thm.arsnova.persistence.SessionStatisticsRepository;
+import de.thm.arsnova.service.score.Score;
+
 public class CouchDbSessionStatisticsRepository extends CouchDbRepositorySupport implements SessionStatisticsRepository {
 	public CouchDbSessionStatisticsRepository(final CouchDbConnector db, final boolean createIfNotExists) {
 		super(Object.class, db, "learning_progress", createIfNotExists);
diff --git a/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbStatisticsRepository.java b/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbStatisticsRepository.java
index 3b927de73..f2f43fb2d 100644
--- a/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbStatisticsRepository.java
+++ b/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbStatisticsRepository.java
@@ -15,10 +15,11 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.persistence.couchdb;
 
-import de.thm.arsnova.model.Statistics;
-import de.thm.arsnova.persistence.StatisticsRepository;
+import java.util.HashSet;
+import java.util.Set;
 import org.ektorp.CouchDbConnector;
 import org.ektorp.DbAccessException;
 import org.ektorp.ViewResult;
@@ -26,8 +27,8 @@ import org.ektorp.support.CouchDbRepositorySupport;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import java.util.HashSet;
-import java.util.Set;
+import de.thm.arsnova.model.Statistics;
+import de.thm.arsnova.persistence.StatisticsRepository;
 
 public class CouchDbStatisticsRepository extends CouchDbRepositorySupport implements StatisticsRepository {
 	private static final Logger logger = LoggerFactory.getLogger(CouchDbStatisticsRepository.class);
diff --git a/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbUserRepository.java b/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbUserRepository.java
index adf972390..819f74c47 100644
--- a/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbUserRepository.java
+++ b/src/main/java/de/thm/arsnova/persistence/couchdb/CouchDbUserRepository.java
@@ -15,11 +15,12 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.persistence.couchdb;
 
 import com.google.common.collect.Lists;
-import de.thm.arsnova.model.UserProfile;
-import de.thm.arsnova.persistence.UserRepository;
+import java.util.ArrayList;
+import java.util.List;
 import org.ektorp.BulkDeleteDocument;
 import org.ektorp.ComplexKey;
 import org.ektorp.CouchDbConnector;
@@ -30,8 +31,8 @@ import org.ektorp.ViewResult;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import java.util.ArrayList;
-import java.util.List;
+import de.thm.arsnova.model.UserProfile;
+import de.thm.arsnova.persistence.UserRepository;
 
 public class CouchDbUserRepository extends CouchDbCrudRepository<UserProfile> implements UserRepository {
 	private static final int BULK_PARTITION_SIZE = 500;
diff --git a/src/main/java/de/thm/arsnova/persistence/couchdb/migrations/MigrateFromLegacyCondition.java b/src/main/java/de/thm/arsnova/persistence/couchdb/migrations/MigrateFromLegacyCondition.java
index 9bd2aec27..69f6bc4bf 100644
--- a/src/main/java/de/thm/arsnova/persistence/couchdb/migrations/MigrateFromLegacyCondition.java
+++ b/src/main/java/de/thm/arsnova/persistence/couchdb/migrations/MigrateFromLegacyCondition.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.persistence.couchdb.migrations;
 
 import org.springframework.context.annotation.Condition;
diff --git a/src/main/java/de/thm/arsnova/persistence/couchdb/migrations/Migration.java b/src/main/java/de/thm/arsnova/persistence/couchdb/migrations/Migration.java
index 9eb4deacc..3ff8265a9 100644
--- a/src/main/java/de/thm/arsnova/persistence/couchdb/migrations/Migration.java
+++ b/src/main/java/de/thm/arsnova/persistence/couchdb/migrations/Migration.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.persistence.couchdb.migrations;
 
 public interface Migration {
diff --git a/src/main/java/de/thm/arsnova/persistence/couchdb/migrations/MigrationExecutor.java b/src/main/java/de/thm/arsnova/persistence/couchdb/migrations/MigrationExecutor.java
index 7dfd9fc03..9a7ee62dc 100644
--- a/src/main/java/de/thm/arsnova/persistence/couchdb/migrations/MigrationExecutor.java
+++ b/src/main/java/de/thm/arsnova/persistence/couchdb/migrations/MigrationExecutor.java
@@ -15,13 +15,8 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-package de.thm.arsnova.persistence.couchdb.migrations;
 
-import de.thm.arsnova.model.MigrationState;
-import org.checkerframework.checker.nullness.qual.NonNull;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-import org.springframework.stereotype.Service;
+package de.thm.arsnova.persistence.couchdb.migrations;
 
 import java.util.Collections;
 import java.util.Comparator;
@@ -29,6 +24,12 @@ import java.util.Date;
 import java.util.List;
 import java.util.Optional;
 import java.util.stream.Collectors;
+import org.checkerframework.checker.nullness.qual.NonNull;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.stereotype.Service;
+
+import de.thm.arsnova.model.MigrationState;
 
 /**
  * Run necessary migrations based on the {@link MigrationState} to adjust data to the current entity models.
diff --git a/src/main/java/de/thm/arsnova/persistence/couchdb/migrations/V2ToV3Migration.java b/src/main/java/de/thm/arsnova/persistence/couchdb/migrations/V2ToV3Migration.java
index 4dcf7462d..054d0a980 100644
--- a/src/main/java/de/thm/arsnova/persistence/couchdb/migrations/V2ToV3Migration.java
+++ b/src/main/java/de/thm/arsnova/persistence/couchdb/migrations/V2ToV3Migration.java
@@ -15,8 +15,25 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.persistence.couchdb.migrations;
 
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Optional;
+import java.util.Set;
+import org.ektorp.DbAccessException;
+import org.ektorp.DocumentNotFoundException;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.annotation.Qualifier;
+import org.springframework.context.annotation.Conditional;
+import org.springframework.stereotype.Service;
+
 import de.thm.arsnova.model.Answer;
 import de.thm.arsnova.model.Comment;
 import de.thm.arsnova.model.Content;
@@ -32,22 +49,6 @@ import de.thm.arsnova.persistence.RoomRepository;
 import de.thm.arsnova.persistence.UserRepository;
 import de.thm.arsnova.persistence.couchdb.support.MangoCouchDbConnector;
 import de.thm.arsnova.persistence.couchdb.support.PagedMangoResponse;
-import org.ektorp.DbAccessException;
-import org.ektorp.DocumentNotFoundException;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-import org.springframework.beans.factory.annotation.Qualifier;
-import org.springframework.context.annotation.Conditional;
-import org.springframework.stereotype.Service;
-
-import java.util.ArrayList;
-import java.util.Collections;
-import java.util.HashMap;
-import java.util.HashSet;
-import java.util.List;
-import java.util.Map;
-import java.util.Optional;
-import java.util.Set;
 
 /**
  * Performs the data migration from version 2 to version 3.
diff --git a/src/main/java/de/thm/arsnova/persistence/couchdb/support/MangoCouchDbConnector.java b/src/main/java/de/thm/arsnova/persistence/couchdb/support/MangoCouchDbConnector.java
index df99fe62e..66b495104 100644
--- a/src/main/java/de/thm/arsnova/persistence/couchdb/support/MangoCouchDbConnector.java
+++ b/src/main/java/de/thm/arsnova/persistence/couchdb/support/MangoCouchDbConnector.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.persistence.couchdb.support;
 
 import com.fasterxml.jackson.annotation.JsonCreator;
@@ -27,7 +28,12 @@ import com.fasterxml.jackson.databind.JavaType;
 import com.fasterxml.jackson.databind.annotation.JsonSerialize;
 import com.fasterxml.jackson.databind.type.TypeFactory;
 import com.fasterxml.jackson.databind.util.Converter;
-import de.thm.arsnova.model.serialization.View;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
 import org.ektorp.CouchDbInstance;
 import org.ektorp.DbAccessException;
 import org.ektorp.http.HttpResponse;
@@ -37,12 +43,7 @@ import org.ektorp.impl.StdCouchDbConnector;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import java.util.ArrayList;
-import java.util.Arrays;
-import java.util.Collections;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
+import de.thm.arsnova.model.serialization.View;
 
 /**
  * This Connector adds a query method which uses CouchDB's Mango API to retrieve data.
diff --git a/src/main/java/de/thm/arsnova/persistence/couchdb/support/MangoQueryResultParser.java b/src/main/java/de/thm/arsnova/persistence/couchdb/support/MangoQueryResultParser.java
index 5841737af..6f58b8a05 100644
--- a/src/main/java/de/thm/arsnova/persistence/couchdb/support/MangoQueryResultParser.java
+++ b/src/main/java/de/thm/arsnova/persistence/couchdb/support/MangoQueryResultParser.java
@@ -15,19 +15,19 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.persistence.couchdb.support;
 
 import com.fasterxml.jackson.core.JsonParser;
 import com.fasterxml.jackson.core.JsonToken;
 import com.fasterxml.jackson.databind.ObjectMapper;
-import org.ektorp.DbAccessException;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
 import java.io.IOException;
 import java.io.InputStream;
 import java.util.ArrayList;
 import java.util.List;
+import org.ektorp.DbAccessException;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 public class MangoQueryResultParser<T> {
 	private static final String DOCS_FIELD_NAME = "docs";
diff --git a/src/main/java/de/thm/arsnova/persistence/couchdb/support/MangoResponseHandler.java b/src/main/java/de/thm/arsnova/persistence/couchdb/support/MangoResponseHandler.java
index 1a0d59d99..a7b8195b1 100644
--- a/src/main/java/de/thm/arsnova/persistence/couchdb/support/MangoResponseHandler.java
+++ b/src/main/java/de/thm/arsnova/persistence/couchdb/support/MangoResponseHandler.java
@@ -15,15 +15,15 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.persistence.couchdb.support;
 
 import com.fasterxml.jackson.databind.ObjectMapper;
+import java.util.List;
 import org.ektorp.http.HttpResponse;
 import org.ektorp.http.StdResponseHandler;
 import org.ektorp.util.Assert;
 
-import java.util.List;
-
 public class MangoResponseHandler<T> extends StdResponseHandler<List<T>> {
 
 	private MangoQueryResultParser<T> parser;
diff --git a/src/main/java/de/thm/arsnova/persistence/couchdb/support/PagedMangoResponse.java b/src/main/java/de/thm/arsnova/persistence/couchdb/support/PagedMangoResponse.java
index c509de579..dd8cbff5d 100644
--- a/src/main/java/de/thm/arsnova/persistence/couchdb/support/PagedMangoResponse.java
+++ b/src/main/java/de/thm/arsnova/persistence/couchdb/support/PagedMangoResponse.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.persistence.couchdb.support;
 
 import java.util.List;
diff --git a/src/main/java/de/thm/arsnova/security/ApplicationPermissionEvaluator.java b/src/main/java/de/thm/arsnova/security/ApplicationPermissionEvaluator.java
index b1a1192b0..71e03b23c 100644
--- a/src/main/java/de/thm/arsnova/security/ApplicationPermissionEvaluator.java
+++ b/src/main/java/de/thm/arsnova/security/ApplicationPermissionEvaluator.java
@@ -15,8 +15,21 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.security;
 
+import java.io.Serializable;
+import java.util.Arrays;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.security.access.PermissionEvaluator;
+import org.springframework.security.access.intercept.RunAsUserToken;
+import org.springframework.security.authentication.AnonymousAuthenticationToken;
+import org.springframework.security.core.Authentication;
+import org.springframework.stereotype.Component;
+
 import de.thm.arsnova.model.Answer;
 import de.thm.arsnova.model.Comment;
 import de.thm.arsnova.model.Content;
@@ -28,18 +41,6 @@ import de.thm.arsnova.persistence.CommentRepository;
 import de.thm.arsnova.persistence.ContentRepository;
 import de.thm.arsnova.persistence.MotdRepository;
 import de.thm.arsnova.persistence.RoomRepository;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.beans.factory.annotation.Value;
-import org.springframework.security.access.PermissionEvaluator;
-import org.springframework.security.access.intercept.RunAsUserToken;
-import org.springframework.security.authentication.AnonymousAuthenticationToken;
-import org.springframework.security.core.Authentication;
-import org.springframework.stereotype.Component;
-
-import java.io.Serializable;
-import java.util.Arrays;
 
 /**
  * Provides access control methods that can be used in annotations.
diff --git a/src/main/java/de/thm/arsnova/security/CasLogoutSuccessHandler.java b/src/main/java/de/thm/arsnova/security/CasLogoutSuccessHandler.java
index 0e37134e1..4ae26b672 100644
--- a/src/main/java/de/thm/arsnova/security/CasLogoutSuccessHandler.java
+++ b/src/main/java/de/thm/arsnova/security/CasLogoutSuccessHandler.java
@@ -15,8 +15,13 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.security;
 
+import java.io.IOException;
+import javax.servlet.ServletException;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.security.core.Authentication;
@@ -24,11 +29,6 @@ import org.springframework.security.web.DefaultRedirectStrategy;
 import org.springframework.security.web.RedirectStrategy;
 import org.springframework.security.web.authentication.logout.LogoutSuccessHandler;
 
-import javax.servlet.ServletException;
-import javax.servlet.http.HttpServletRequest;
-import javax.servlet.http.HttpServletResponse;
-import java.io.IOException;
-
 /**
  * This class gets called when a user has been successfully logged out from CAS.
  */
diff --git a/src/main/java/de/thm/arsnova/security/CasUserDetailsService.java b/src/main/java/de/thm/arsnova/security/CasUserDetailsService.java
index cd04bcede..59dce24a0 100644
--- a/src/main/java/de/thm/arsnova/security/CasUserDetailsService.java
+++ b/src/main/java/de/thm/arsnova/security/CasUserDetailsService.java
@@ -15,10 +15,11 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.security;
 
-import de.thm.arsnova.model.UserProfile;
-import de.thm.arsnova.service.UserService;
+import java.util.HashSet;
+import java.util.Set;
 import org.jasig.cas.client.validation.Assertion;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.security.cas.userdetails.AbstractCasAssertionUserDetailsService;
@@ -27,8 +28,8 @@ import org.springframework.security.core.authority.SimpleGrantedAuthority;
 import org.springframework.security.core.userdetails.UserDetails;
 import org.springframework.stereotype.Service;
 
-import java.util.HashSet;
-import java.util.Set;
+import de.thm.arsnova.model.UserProfile;
+import de.thm.arsnova.service.UserService;
 
 /**
  * Class to load a user based on the results from CAS.
diff --git a/src/main/java/de/thm/arsnova/security/CustomLdapUserDetailsMapper.java b/src/main/java/de/thm/arsnova/security/CustomLdapUserDetailsMapper.java
index 7ea5d4310..4efa3c1c8 100644
--- a/src/main/java/de/thm/arsnova/security/CustomLdapUserDetailsMapper.java
+++ b/src/main/java/de/thm/arsnova/security/CustomLdapUserDetailsMapper.java
@@ -15,10 +15,11 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.security;
 
-import de.thm.arsnova.model.UserProfile;
-import de.thm.arsnova.service.UserService;
+import java.util.Collection;
+import java.util.HashSet;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.beans.factory.annotation.Autowired;
@@ -28,8 +29,8 @@ import org.springframework.security.core.authority.SimpleGrantedAuthority;
 import org.springframework.security.core.userdetails.UserDetails;
 import org.springframework.security.ldap.userdetails.LdapUserDetailsMapper;
 
-import java.util.Collection;
-import java.util.HashSet;
+import de.thm.arsnova.model.UserProfile;
+import de.thm.arsnova.service.UserService;
 
 /**
  * Replaces the user ID provided by the authenticating user with the one that is part of LDAP object. This is necessary
diff --git a/src/main/java/de/thm/arsnova/security/GuestUserDetailsService.java b/src/main/java/de/thm/arsnova/security/GuestUserDetailsService.java
index e274c34bd..01b5af53a 100644
--- a/src/main/java/de/thm/arsnova/security/GuestUserDetailsService.java
+++ b/src/main/java/de/thm/arsnova/security/GuestUserDetailsService.java
@@ -15,10 +15,11 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.security;
 
-import de.thm.arsnova.model.UserProfile;
-import de.thm.arsnova.service.UserService;
+import java.util.Collection;
+import java.util.HashSet;
 import org.springframework.security.core.GrantedAuthority;
 import org.springframework.security.core.authority.SimpleGrantedAuthority;
 import org.springframework.security.core.userdetails.UserDetails;
@@ -26,8 +27,8 @@ import org.springframework.security.core.userdetails.UserDetailsService;
 import org.springframework.security.core.userdetails.UsernameNotFoundException;
 import org.springframework.stereotype.Service;
 
-import java.util.Collection;
-import java.util.HashSet;
+import de.thm.arsnova.model.UserProfile;
+import de.thm.arsnova.service.UserService;
 
 /**
  * Loads UserDetails for a guest user ({@link UserProfile.AuthProvider#ARSNOVA_GUEST}) based on the username (guest
diff --git a/src/main/java/de/thm/arsnova/security/LoginAuthenticationFailureHandler.java b/src/main/java/de/thm/arsnova/security/LoginAuthenticationFailureHandler.java
index f625f049b..c86605d86 100644
--- a/src/main/java/de/thm/arsnova/security/LoginAuthenticationFailureHandler.java
+++ b/src/main/java/de/thm/arsnova/security/LoginAuthenticationFailureHandler.java
@@ -15,18 +15,18 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-package de.thm.arsnova.security;
 
-import org.springframework.security.core.AuthenticationException;
-import org.springframework.security.web.DefaultRedirectStrategy;
-import org.springframework.security.web.RedirectStrategy;
-import org.springframework.security.web.authentication.SimpleUrlAuthenticationFailureHandler;
+package de.thm.arsnova.security;
 
+import java.io.IOException;
 import javax.servlet.ServletException;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 import javax.servlet.http.HttpSession;
-import java.io.IOException;
+import org.springframework.security.core.AuthenticationException;
+import org.springframework.security.web.DefaultRedirectStrategy;
+import org.springframework.security.web.RedirectStrategy;
+import org.springframework.security.web.authentication.SimpleUrlAuthenticationFailureHandler;
 
 
 /**
diff --git a/src/main/java/de/thm/arsnova/security/LoginAuthenticationSucessHandler.java b/src/main/java/de/thm/arsnova/security/LoginAuthenticationSucessHandler.java
index 58839bbb5..ce57a0fa8 100644
--- a/src/main/java/de/thm/arsnova/security/LoginAuthenticationSucessHandler.java
+++ b/src/main/java/de/thm/arsnova/security/LoginAuthenticationSucessHandler.java
@@ -15,13 +15,13 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-package de.thm.arsnova.security;
 
-import org.springframework.security.web.authentication.SimpleUrlAuthenticationSuccessHandler;
+package de.thm.arsnova.security;
 
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 import javax.servlet.http.HttpSession;
+import org.springframework.security.web.authentication.SimpleUrlAuthenticationSuccessHandler;
 
 /**
  * This class gets called when a user successfully logged in.
diff --git a/src/main/java/de/thm/arsnova/security/RegisteredUserDetailsService.java b/src/main/java/de/thm/arsnova/security/RegisteredUserDetailsService.java
index 948d96f03..d77344e5c 100644
--- a/src/main/java/de/thm/arsnova/security/RegisteredUserDetailsService.java
+++ b/src/main/java/de/thm/arsnova/security/RegisteredUserDetailsService.java
@@ -15,10 +15,12 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.security;
 
-import de.thm.arsnova.model.UserProfile;
-import de.thm.arsnova.service.UserService;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.HashSet;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.security.core.GrantedAuthority;
 import org.springframework.security.core.authority.SimpleGrantedAuthority;
@@ -27,9 +29,8 @@ import org.springframework.security.core.userdetails.UserDetailsService;
 import org.springframework.security.core.userdetails.UsernameNotFoundException;
 import org.springframework.stereotype.Service;
 
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.HashSet;
+import de.thm.arsnova.model.UserProfile;
+import de.thm.arsnova.service.UserService;
 
 /**
  * Loads UserDetails for a registered user ({@link UserProfile.AuthProvider#ARSNOVA}) based on the username (loginId).
diff --git a/src/main/java/de/thm/arsnova/security/User.java b/src/main/java/de/thm/arsnova/security/User.java
index 2c4099003..8a1f51e15 100644
--- a/src/main/java/de/thm/arsnova/security/User.java
+++ b/src/main/java/de/thm/arsnova/security/User.java
@@ -15,13 +15,14 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.security;
 
-import de.thm.arsnova.model.UserProfile;
-import de.thm.arsnova.model.migration.v2.ClientAuthentication;
+import java.util.Collection;
 import org.springframework.security.core.GrantedAuthority;
 
-import java.util.Collection;
+import de.thm.arsnova.model.UserProfile;
+import de.thm.arsnova.model.migration.v2.ClientAuthentication;
 
 /**
  * UserDetails implementation which identifies a user by internal (database) and external (AuthProvider + loginId) ID.
diff --git a/src/main/java/de/thm/arsnova/security/jwt/JwtAuthenticationProvider.java b/src/main/java/de/thm/arsnova/security/jwt/JwtAuthenticationProvider.java
index 58725b3f9..2b743b994 100644
--- a/src/main/java/de/thm/arsnova/security/jwt/JwtAuthenticationProvider.java
+++ b/src/main/java/de/thm/arsnova/security/jwt/JwtAuthenticationProvider.java
@@ -15,14 +15,16 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.security.jwt;
 
-import de.thm.arsnova.security.User;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.security.authentication.AuthenticationProvider;
 import org.springframework.security.core.Authentication;
 import org.springframework.security.core.AuthenticationException;
 
+import de.thm.arsnova.security.User;
+
 public class JwtAuthenticationProvider implements AuthenticationProvider {
 	private JwtService jwtService;
 
diff --git a/src/main/java/de/thm/arsnova/security/jwt/JwtService.java b/src/main/java/de/thm/arsnova/security/jwt/JwtService.java
index 8592d0e81..3ebafe67a 100644
--- a/src/main/java/de/thm/arsnova/security/jwt/JwtService.java
+++ b/src/main/java/de/thm/arsnova/security/jwt/JwtService.java
@@ -15,20 +15,13 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.security.jwt;
 
 import com.auth0.jwt.JWT;
 import com.auth0.jwt.JWTVerifier;
 import com.auth0.jwt.algorithms.Algorithm;
 import com.auth0.jwt.interfaces.DecodedJWT;
-import de.thm.arsnova.model.UserProfile;
-import de.thm.arsnova.security.User;
-import de.thm.arsnova.service.UserService;
-import org.springframework.beans.factory.annotation.Value;
-import org.springframework.security.core.GrantedAuthority;
-import org.springframework.security.core.authority.SimpleGrantedAuthority;
-import org.springframework.stereotype.Service;
-
 import java.io.UnsupportedEncodingException;
 import java.time.Duration;
 import java.time.LocalDateTime;
@@ -37,6 +30,14 @@ import java.time.temporal.TemporalAmount;
 import java.util.Collection;
 import java.util.Date;
 import java.util.stream.Collectors;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.security.core.GrantedAuthority;
+import org.springframework.security.core.authority.SimpleGrantedAuthority;
+import org.springframework.stereotype.Service;
+
+import de.thm.arsnova.model.UserProfile;
+import de.thm.arsnova.security.User;
+import de.thm.arsnova.service.UserService;
 
 @Service
 public class JwtService {
diff --git a/src/main/java/de/thm/arsnova/security/jwt/JwtToken.java b/src/main/java/de/thm/arsnova/security/jwt/JwtToken.java
index 2117214e2..69fff454b 100644
--- a/src/main/java/de/thm/arsnova/security/jwt/JwtToken.java
+++ b/src/main/java/de/thm/arsnova/security/jwt/JwtToken.java
@@ -15,14 +15,15 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.security.jwt;
 
-import de.thm.arsnova.security.User;
+import java.util.Collection;
+import java.util.Collections;
 import org.springframework.security.authentication.AbstractAuthenticationToken;
 import org.springframework.security.core.GrantedAuthority;
 
-import java.util.Collection;
-import java.util.Collections;
+import de.thm.arsnova.security.User;
 
 public class JwtToken extends AbstractAuthenticationToken {
 	private String token;
diff --git a/src/main/java/de/thm/arsnova/security/jwt/JwtTokenFilter.java b/src/main/java/de/thm/arsnova/security/jwt/JwtTokenFilter.java
index c40c92e48..b076c61f9 100644
--- a/src/main/java/de/thm/arsnova/security/jwt/JwtTokenFilter.java
+++ b/src/main/java/de/thm/arsnova/security/jwt/JwtTokenFilter.java
@@ -15,8 +15,15 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.security.jwt;
 
+import java.io.IOException;
+import javax.servlet.FilterChain;
+import javax.servlet.ServletException;
+import javax.servlet.ServletRequest;
+import javax.servlet.ServletResponse;
+import javax.servlet.http.HttpServletRequest;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.beans.factory.annotation.Autowired;
@@ -25,13 +32,6 @@ import org.springframework.security.core.context.SecurityContextHolder;
 import org.springframework.stereotype.Component;
 import org.springframework.web.filter.GenericFilterBean;
 
-import javax.servlet.FilterChain;
-import javax.servlet.ServletException;
-import javax.servlet.ServletRequest;
-import javax.servlet.ServletResponse;
-import javax.servlet.http.HttpServletRequest;
-import java.io.IOException;
-
 @Component
 public class JwtTokenFilter extends GenericFilterBean {
 	private static final String JWT_HEADER_NAME = "Arsnova-Auth-Token";
diff --git a/src/main/java/de/thm/arsnova/security/pac4j/OAuthToken.java b/src/main/java/de/thm/arsnova/security/pac4j/OAuthToken.java
index 31888b326..31d05e17c 100644
--- a/src/main/java/de/thm/arsnova/security/pac4j/OAuthToken.java
+++ b/src/main/java/de/thm/arsnova/security/pac4j/OAuthToken.java
@@ -15,14 +15,15 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.security.pac4j;
 
-import de.thm.arsnova.security.User;
+import java.util.Collection;
 import org.pac4j.core.profile.CommonProfile;
 import org.springframework.security.authentication.AbstractAuthenticationToken;
 import org.springframework.security.core.GrantedAuthority;
 
-import java.util.Collection;
+import de.thm.arsnova.security.User;
 
 /**
  * Authentication token implementation for OAuth.
diff --git a/src/main/java/de/thm/arsnova/security/pac4j/OauthAuthenticationProvider.java b/src/main/java/de/thm/arsnova/security/pac4j/OauthAuthenticationProvider.java
index f1708d894..6cbe8f9d2 100644
--- a/src/main/java/de/thm/arsnova/security/pac4j/OauthAuthenticationProvider.java
+++ b/src/main/java/de/thm/arsnova/security/pac4j/OauthAuthenticationProvider.java
@@ -15,9 +15,9 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.security.pac4j;
 
-import de.thm.arsnova.security.User;
 import org.pac4j.core.profile.CommonProfile;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.security.authentication.AuthenticationProvider;
@@ -25,6 +25,8 @@ import org.springframework.security.core.Authentication;
 import org.springframework.security.core.AuthenticationException;
 import org.springframework.stereotype.Component;
 
+import de.thm.arsnova.security.User;
+
 /**
  * Sets up the SecurityContext OAuth users.
  *
diff --git a/src/main/java/de/thm/arsnova/security/pac4j/OauthCallbackFilter.java b/src/main/java/de/thm/arsnova/security/pac4j/OauthCallbackFilter.java
index 4746e07cb..a4f7efd04 100644
--- a/src/main/java/de/thm/arsnova/security/pac4j/OauthCallbackFilter.java
+++ b/src/main/java/de/thm/arsnova/security/pac4j/OauthCallbackFilter.java
@@ -15,8 +15,13 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.security.pac4j;
 
+import java.util.Collections;
+import java.util.List;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
 import org.pac4j.core.client.Client;
 import org.pac4j.core.client.Clients;
 import org.pac4j.core.client.IndirectClient;
@@ -37,11 +42,6 @@ import org.springframework.security.web.authentication.AbstractAuthenticationPro
 import org.springframework.security.web.util.matcher.AntPathRequestMatcher;
 import org.springframework.stereotype.Component;
 
-import javax.servlet.http.HttpServletRequest;
-import javax.servlet.http.HttpServletResponse;
-import java.util.Collections;
-import java.util.List;
-
 /**
  * Handles callback requests by login redirects from OAuth providers.
  *
diff --git a/src/main/java/de/thm/arsnova/security/pac4j/OauthUserDetailsService.java b/src/main/java/de/thm/arsnova/security/pac4j/OauthUserDetailsService.java
index 16878a136..f81eec48f 100644
--- a/src/main/java/de/thm/arsnova/security/pac4j/OauthUserDetailsService.java
+++ b/src/main/java/de/thm/arsnova/security/pac4j/OauthUserDetailsService.java
@@ -15,11 +15,11 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.security.pac4j;
 
-import de.thm.arsnova.model.UserProfile;
-import de.thm.arsnova.security.User;
-import de.thm.arsnova.service.UserService;
+import java.util.Collection;
+import java.util.HashSet;
 import org.pac4j.oauth.profile.facebook.FacebookProfile;
 import org.pac4j.oauth.profile.twitter.TwitterProfile;
 import org.pac4j.oidc.profile.OidcProfile;
@@ -30,8 +30,9 @@ import org.springframework.security.core.userdetails.AuthenticationUserDetailsSe
 import org.springframework.security.core.userdetails.UsernameNotFoundException;
 import org.springframework.stereotype.Service;
 
-import java.util.Collection;
-import java.util.HashSet;
+import de.thm.arsnova.model.UserProfile;
+import de.thm.arsnova.security.User;
+import de.thm.arsnova.service.UserService;
 
 /**
  * Loads UserDetails for an OAuth user (e.g. {@link UserProfile.AuthProvider#GOOGLE}) based on an unique identifier
diff --git a/src/main/java/de/thm/arsnova/security/package-info.java b/src/main/java/de/thm/arsnova/security/package-info.java
index 193d89746..399923049 100644
--- a/src/main/java/de/thm/arsnova/security/package-info.java
+++ b/src/main/java/de/thm/arsnova/security/package-info.java
@@ -2,4 +2,5 @@
  * @author Paul-Christian Volkmer
  *
  */
+
 package de.thm.arsnova.security;
diff --git a/src/main/java/de/thm/arsnova/service/AnswerService.java b/src/main/java/de/thm/arsnova/service/AnswerService.java
index 58cd210a5..594d154d3 100644
--- a/src/main/java/de/thm/arsnova/service/AnswerService.java
+++ b/src/main/java/de/thm/arsnova/service/AnswerService.java
@@ -15,15 +15,16 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.service;
 
+import java.util.List;
+import java.util.Map;
+
 import de.thm.arsnova.model.Answer;
 import de.thm.arsnova.model.AnswerStatistics;
 import de.thm.arsnova.model.TextAnswer;
 
-import java.util.List;
-import java.util.Map;
-
 public interface AnswerService extends EntityService<Answer> {
 	Answer getMyAnswer(String contentId);
 
diff --git a/src/main/java/de/thm/arsnova/service/AnswerServiceImpl.java b/src/main/java/de/thm/arsnova/service/AnswerServiceImpl.java
index 021e0b1d7..96c1ce6e1 100644
--- a/src/main/java/de/thm/arsnova/service/AnswerServiceImpl.java
+++ b/src/main/java/de/thm/arsnova/service/AnswerServiceImpl.java
@@ -15,8 +15,27 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.	 If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.service;
 
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Queue;
+import java.util.concurrent.ConcurrentLinkedQueue;
+import org.ektorp.DbAccessException;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.beans.factory.annotation.Qualifier;
+import org.springframework.context.event.EventListener;
+import org.springframework.http.converter.json.MappingJackson2HttpMessageConverter;
+import org.springframework.scheduling.annotation.Scheduled;
+import org.springframework.security.access.annotation.Secured;
+import org.springframework.security.access.prepost.PreAuthorize;
+import org.springframework.stereotype.Service;
+
 import de.thm.arsnova.event.AfterCreationEvent;
 import de.thm.arsnova.event.BeforeCreationEvent;
 import de.thm.arsnova.event.BeforeDeletionEvent;
@@ -30,24 +49,6 @@ import de.thm.arsnova.persistence.AnswerRepository;
 import de.thm.arsnova.security.User;
 import de.thm.arsnova.web.exceptions.NotFoundException;
 import de.thm.arsnova.web.exceptions.UnauthorizedException;
-import org.ektorp.DbAccessException;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.beans.factory.annotation.Qualifier;
-import org.springframework.context.event.EventListener;
-import org.springframework.http.converter.json.MappingJackson2HttpMessageConverter;
-import org.springframework.scheduling.annotation.Scheduled;
-import org.springframework.security.access.annotation.Secured;
-import org.springframework.security.access.prepost.PreAuthorize;
-import org.springframework.stereotype.Service;
-
-import java.util.ArrayList;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
-import java.util.Queue;
-import java.util.concurrent.ConcurrentLinkedQueue;
 
 /**
  * Performs all answer related operations.
diff --git a/src/main/java/de/thm/arsnova/service/AttachmentService.java b/src/main/java/de/thm/arsnova/service/AttachmentService.java
index cae650099..5be66aa84 100644
--- a/src/main/java/de/thm/arsnova/service/AttachmentService.java
+++ b/src/main/java/de/thm/arsnova/service/AttachmentService.java
@@ -15,11 +15,13 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.service;
 
-import de.thm.arsnova.model.Attachment;
 import org.springframework.web.multipart.MultipartFile;
 
+import de.thm.arsnova.model.Attachment;
+
 public interface AttachmentService extends EntityService<Attachment> {
 	void upload(Attachment attachment, MultipartFile file);
 	void download(Attachment attachment);
diff --git a/src/main/java/de/thm/arsnova/service/AttachmentServiceImpl.java b/src/main/java/de/thm/arsnova/service/AttachmentServiceImpl.java
index ad8b4bae5..d0da4bf28 100644
--- a/src/main/java/de/thm/arsnova/service/AttachmentServiceImpl.java
+++ b/src/main/java/de/thm/arsnova/service/AttachmentServiceImpl.java
@@ -15,14 +15,16 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.service;
 
-import de.thm.arsnova.model.Attachment;
-import de.thm.arsnova.persistence.AttachmentRepository;
 import org.springframework.beans.factory.annotation.Qualifier;
 import org.springframework.http.converter.json.MappingJackson2HttpMessageConverter;
 import org.springframework.web.multipart.MultipartFile;
 
+import de.thm.arsnova.model.Attachment;
+import de.thm.arsnova.persistence.AttachmentRepository;
+
 public class AttachmentServiceImpl extends DefaultEntityServiceImpl<Attachment> implements AttachmentService {
 	private AttachmentRepository attachmentRepository;
 
diff --git a/src/main/java/de/thm/arsnova/service/CommentFindQueryService.java b/src/main/java/de/thm/arsnova/service/CommentFindQueryService.java
index acdecead3..f8841bb6e 100644
--- a/src/main/java/de/thm/arsnova/service/CommentFindQueryService.java
+++ b/src/main/java/de/thm/arsnova/service/CommentFindQueryService.java
@@ -15,14 +15,15 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-package de.thm.arsnova.service;
 
-import de.thm.arsnova.model.Comment;
-import de.thm.arsnova.model.FindQuery;
-import org.springframework.stereotype.Service;
+package de.thm.arsnova.service;
 
 import java.util.HashSet;
 import java.util.Set;
+import org.springframework.stereotype.Service;
+
+import de.thm.arsnova.model.Comment;
+import de.thm.arsnova.model.FindQuery;
 
 @Service
 public class CommentFindQueryService implements FindQueryService<Comment> {
diff --git a/src/main/java/de/thm/arsnova/service/CommentService.java b/src/main/java/de/thm/arsnova/service/CommentService.java
index 336f0d578..efddd0a52 100644
--- a/src/main/java/de/thm/arsnova/service/CommentService.java
+++ b/src/main/java/de/thm/arsnova/service/CommentService.java
@@ -15,14 +15,15 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-package de.thm.arsnova.service;
 
-import de.thm.arsnova.model.Comment;
-import de.thm.arsnova.model.migration.v2.CommentReadingCount;
+package de.thm.arsnova.service;
 
 import java.io.IOException;
 import java.util.List;
 
+import de.thm.arsnova.model.Comment;
+import de.thm.arsnova.model.migration.v2.CommentReadingCount;
+
 public interface CommentService extends EntityService<Comment> {
 	int count(String roomId);
 
diff --git a/src/main/java/de/thm/arsnova/service/CommentServiceImpl.java b/src/main/java/de/thm/arsnova/service/CommentServiceImpl.java
index 1613089ee..0ee2f04a7 100644
--- a/src/main/java/de/thm/arsnova/service/CommentServiceImpl.java
+++ b/src/main/java/de/thm/arsnova/service/CommentServiceImpl.java
@@ -15,8 +15,21 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.service;
 
+import java.io.IOException;
+import java.util.Date;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import org.springframework.beans.factory.annotation.Qualifier;
+import org.springframework.context.event.EventListener;
+import org.springframework.http.converter.json.MappingJackson2HttpMessageConverter;
+import org.springframework.security.access.annotation.Secured;
+import org.springframework.security.access.prepost.PreAuthorize;
+import org.springframework.stereotype.Service;
+
 import de.thm.arsnova.event.BeforeDeletionEvent;
 import de.thm.arsnova.model.Comment;
 import de.thm.arsnova.model.Room;
@@ -26,18 +39,6 @@ import de.thm.arsnova.security.User;
 import de.thm.arsnova.web.exceptions.ForbiddenException;
 import de.thm.arsnova.web.exceptions.NotFoundException;
 import de.thm.arsnova.web.exceptions.UnauthorizedException;
-import org.springframework.beans.factory.annotation.Qualifier;
-import org.springframework.context.event.EventListener;
-import org.springframework.http.converter.json.MappingJackson2HttpMessageConverter;
-import org.springframework.security.access.annotation.Secured;
-import org.springframework.security.access.prepost.PreAuthorize;
-import org.springframework.stereotype.Service;
-
-import java.io.IOException;
-import java.util.Date;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
 
 /**
  * Performs all comment related operations.
diff --git a/src/main/java/de/thm/arsnova/service/ContentFindQueryService.java b/src/main/java/de/thm/arsnova/service/ContentFindQueryService.java
index c75a5c86c..0a20659cc 100644
--- a/src/main/java/de/thm/arsnova/service/ContentFindQueryService.java
+++ b/src/main/java/de/thm/arsnova/service/ContentFindQueryService.java
@@ -15,15 +15,16 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-package de.thm.arsnova.service;
 
-import de.thm.arsnova.model.Content;
-import de.thm.arsnova.model.FindQuery;
-import org.springframework.stereotype.Service;
+package de.thm.arsnova.service;
 
 import java.util.HashSet;
 import java.util.List;
 import java.util.Set;
+import org.springframework.stereotype.Service;
+
+import de.thm.arsnova.model.Content;
+import de.thm.arsnova.model.FindQuery;
 
 @Service
 public class ContentFindQueryService implements FindQueryService<Content> {
diff --git a/src/main/java/de/thm/arsnova/service/ContentService.java b/src/main/java/de/thm/arsnova/service/ContentService.java
index 35fc2d644..25e0c7285 100644
--- a/src/main/java/de/thm/arsnova/service/ContentService.java
+++ b/src/main/java/de/thm/arsnova/service/ContentService.java
@@ -15,13 +15,14 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.	 If not, see <http://www.gnu.org/licenses/>.
  */
-package de.thm.arsnova.service;
 
-import de.thm.arsnova.model.Content;
+package de.thm.arsnova.service;
 
 import java.io.IOException;
 import java.util.List;
 
+import de.thm.arsnova.model.Content;
+
 /**
  * The functionality the question service should provide.
  */
diff --git a/src/main/java/de/thm/arsnova/service/ContentServiceImpl.java b/src/main/java/de/thm/arsnova/service/ContentServiceImpl.java
index 4418f2511..eb345cff9 100644
--- a/src/main/java/de/thm/arsnova/service/ContentServiceImpl.java
+++ b/src/main/java/de/thm/arsnova/service/ContentServiceImpl.java
@@ -15,18 +15,18 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.	 If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.service;
 
-import de.thm.arsnova.event.BeforeDeletionEvent;
-import de.thm.arsnova.model.Content;
-import de.thm.arsnova.model.Room;
-import de.thm.arsnova.model.Room.ContentGroup;
-import de.thm.arsnova.persistence.AnswerRepository;
-import de.thm.arsnova.persistence.ContentRepository;
-import de.thm.arsnova.persistence.LogEntryRepository;
-import de.thm.arsnova.security.User;
-import de.thm.arsnova.web.exceptions.NotFoundException;
-import de.thm.arsnova.web.exceptions.UnauthorizedException;
+import java.io.IOException;
+import java.util.Collections;
+import java.util.Date;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import java.util.stream.Collectors;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.beans.factory.annotation.Autowired;
@@ -39,15 +39,16 @@ import org.springframework.security.access.annotation.Secured;
 import org.springframework.security.access.prepost.PreAuthorize;
 import org.springframework.stereotype.Service;
 
-import java.io.IOException;
-import java.util.Collections;
-import java.util.Date;
-import java.util.HashMap;
-import java.util.HashSet;
-import java.util.List;
-import java.util.Map;
-import java.util.Set;
-import java.util.stream.Collectors;
+import de.thm.arsnova.event.BeforeDeletionEvent;
+import de.thm.arsnova.model.Content;
+import de.thm.arsnova.model.Room;
+import de.thm.arsnova.model.Room.ContentGroup;
+import de.thm.arsnova.persistence.AnswerRepository;
+import de.thm.arsnova.persistence.ContentRepository;
+import de.thm.arsnova.persistence.LogEntryRepository;
+import de.thm.arsnova.security.User;
+import de.thm.arsnova.web.exceptions.NotFoundException;
+import de.thm.arsnova.web.exceptions.UnauthorizedException;
 
 /**
  * Performs all content related operations.
diff --git a/src/main/java/de/thm/arsnova/service/DefaultEntityServiceImpl.java b/src/main/java/de/thm/arsnova/service/DefaultEntityServiceImpl.java
index b1a597243..b303c12c4 100644
--- a/src/main/java/de/thm/arsnova/service/DefaultEntityServiceImpl.java
+++ b/src/main/java/de/thm/arsnova/service/DefaultEntityServiceImpl.java
@@ -15,11 +15,26 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.service;
 
 import com.fasterxml.jackson.databind.JsonNode;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.ObjectReader;
+import java.io.IOException;
+import java.util.Date;
+import java.util.Map;
+import java.util.function.Function;
+import org.springframework.cache.annotation.CacheEvict;
+import org.springframework.cache.annotation.CachePut;
+import org.springframework.cache.annotation.Cacheable;
+import org.springframework.context.ApplicationEventPublisher;
+import org.springframework.context.ApplicationEventPublisherAware;
+import org.springframework.context.event.EventListener;
+import org.springframework.security.access.prepost.PreAuthorize;
+import org.springframework.security.access.prepost.PreFilter;
+import org.springframework.stereotype.Component;
+
 import de.thm.arsnova.event.AfterCreationEvent;
 import de.thm.arsnova.event.AfterDeletionEvent;
 import de.thm.arsnova.event.AfterFullUpdateEvent;
@@ -33,21 +48,6 @@ import de.thm.arsnova.model.Entity;
 import de.thm.arsnova.model.serialization.View;
 import de.thm.arsnova.persistence.CrudRepository;
 
-import org.springframework.cache.annotation.CacheEvict;
-import org.springframework.cache.annotation.CachePut;
-import org.springframework.cache.annotation.Cacheable;
-import org.springframework.context.ApplicationEventPublisher;
-import org.springframework.context.ApplicationEventPublisherAware;
-import org.springframework.context.event.EventListener;
-import org.springframework.security.access.prepost.PreAuthorize;
-import org.springframework.security.access.prepost.PreFilter;
-import org.springframework.stereotype.Component;
-
-import java.io.IOException;
-import java.util.Date;
-import java.util.Map;
-import java.util.function.Function;
-
 /**
  * Default implementation of {@link EntityService} which provides CRUD operations for entities independently from the
  * underlying persistence implementation. Authorization for entities is checked before any operation is performed.
diff --git a/src/main/java/de/thm/arsnova/service/EntityService.java b/src/main/java/de/thm/arsnova/service/EntityService.java
index 51bb56a7e..61897e68b 100644
--- a/src/main/java/de/thm/arsnova/service/EntityService.java
+++ b/src/main/java/de/thm/arsnova/service/EntityService.java
@@ -15,15 +15,16 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-package de.thm.arsnova.service;
 
-import de.thm.arsnova.model.Entity;
-import org.springframework.security.access.prepost.PreAuthorize;
-import org.springframework.security.access.prepost.PreFilter;
+package de.thm.arsnova.service;
 
 import java.io.IOException;
 import java.util.Map;
 import java.util.function.Function;
+import org.springframework.security.access.prepost.PreAuthorize;
+import org.springframework.security.access.prepost.PreFilter;
+
+import de.thm.arsnova.model.Entity;
 
 /**
  * Provides CRUD operations for entities independently from the underlying persistence implementation.
diff --git a/src/main/java/de/thm/arsnova/service/FeedbackService.java b/src/main/java/de/thm/arsnova/service/FeedbackService.java
index d096f8fb2..b36336af3 100644
--- a/src/main/java/de/thm/arsnova/service/FeedbackService.java
+++ b/src/main/java/de/thm/arsnova/service/FeedbackService.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.service;
 
 import de.thm.arsnova.model.Feedback;
diff --git a/src/main/java/de/thm/arsnova/service/FeedbackServiceImpl.java b/src/main/java/de/thm/arsnova/service/FeedbackServiceImpl.java
index a17897c26..3de6be8f5 100644
--- a/src/main/java/de/thm/arsnova/service/FeedbackServiceImpl.java
+++ b/src/main/java/de/thm/arsnova/service/FeedbackServiceImpl.java
@@ -15,21 +15,26 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.service;
 
-import de.thm.arsnova.event.DeleteFeedbackForRoomsEvent;
-import de.thm.arsnova.event.NewFeedbackEvent;
-import de.thm.arsnova.model.Feedback;
-import de.thm.arsnova.model.Room;
-import de.thm.arsnova.web.exceptions.NoContentException;
-import de.thm.arsnova.web.exceptions.NotFoundException;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
 import org.springframework.beans.factory.annotation.Value;
 import org.springframework.context.ApplicationEventPublisher;
 import org.springframework.context.ApplicationEventPublisherAware;
 import org.springframework.scheduling.annotation.Scheduled;
 import org.springframework.stereotype.Service;
 
-import java.util.*;
+import de.thm.arsnova.event.DeleteFeedbackForRoomsEvent;
+import de.thm.arsnova.event.NewFeedbackEvent;
+import de.thm.arsnova.model.Feedback;
+import de.thm.arsnova.model.Room;
+import de.thm.arsnova.web.exceptions.NoContentException;
+import de.thm.arsnova.web.exceptions.NotFoundException;
 
 /**
  * Performs all feedback related operations.
diff --git a/src/main/java/de/thm/arsnova/service/FeedbackStorageService.java b/src/main/java/de/thm/arsnova/service/FeedbackStorageService.java
index d2add366c..0a5434684 100644
--- a/src/main/java/de/thm/arsnova/service/FeedbackStorageService.java
+++ b/src/main/java/de/thm/arsnova/service/FeedbackStorageService.java
@@ -15,14 +15,15 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-package de.thm.arsnova.service;
 
-import de.thm.arsnova.model.Feedback;
-import de.thm.arsnova.model.Room;
+package de.thm.arsnova.service;
 
 import java.util.List;
 import java.util.Map;
 
+import de.thm.arsnova.model.Feedback;
+import de.thm.arsnova.model.Room;
+
 public interface FeedbackStorageService {
 	Feedback getByRoom(Room room);
 	Integer getByRoomAndUserId(Room room, String userId);
diff --git a/src/main/java/de/thm/arsnova/service/FeedbackStorageServiceImpl.java b/src/main/java/de/thm/arsnova/service/FeedbackStorageServiceImpl.java
index e85713d68..82a6e4250 100644
--- a/src/main/java/de/thm/arsnova/service/FeedbackStorageServiceImpl.java
+++ b/src/main/java/de/thm/arsnova/service/FeedbackStorageServiceImpl.java
@@ -15,15 +15,8 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-package de.thm.arsnova.service;
 
-import de.thm.arsnova.model.Feedback;
-import de.thm.arsnova.model.Room;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-import org.springframework.stereotype.Service;
-import org.springframework.transaction.annotation.Isolation;
-import org.springframework.transaction.annotation.Transactional;
+package de.thm.arsnova.service;
 
 import java.util.ArrayList;
 import java.util.Date;
@@ -32,6 +25,14 @@ import java.util.List;
 import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.TimeUnit;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Isolation;
+import org.springframework.transaction.annotation.Transactional;
+
+import de.thm.arsnova.model.Feedback;
+import de.thm.arsnova.model.Room;
 
 /**
  * In-memory storage of feedback data.
diff --git a/src/main/java/de/thm/arsnova/service/FindQueryService.java b/src/main/java/de/thm/arsnova/service/FindQueryService.java
index 24d4e8e40..ebb5e2d57 100644
--- a/src/main/java/de/thm/arsnova/service/FindQueryService.java
+++ b/src/main/java/de/thm/arsnova/service/FindQueryService.java
@@ -15,13 +15,14 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.service;
 
+import java.util.Set;
+
 import de.thm.arsnova.model.Entity;
 import de.thm.arsnova.model.FindQuery;
 
-import java.util.Set;
-
 /**
  *
  * @param <E> Entity type
diff --git a/src/main/java/de/thm/arsnova/service/MotdService.java b/src/main/java/de/thm/arsnova/service/MotdService.java
index f03740ddd..ca328ef7e 100644
--- a/src/main/java/de/thm/arsnova/service/MotdService.java
+++ b/src/main/java/de/thm/arsnova/service/MotdService.java
@@ -15,13 +15,14 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-package de.thm.arsnova.service;
 
-import de.thm.arsnova.model.Motd;
+package de.thm.arsnova.service;
 
 import java.util.Date;
 import java.util.List;
 
+import de.thm.arsnova.model.Motd;
+
 /**
  * The functionality the motd service should provide.
  */
diff --git a/src/main/java/de/thm/arsnova/service/MotdServiceImpl.java b/src/main/java/de/thm/arsnova/service/MotdServiceImpl.java
index 589d0bdaa..f9b18be65 100644
--- a/src/main/java/de/thm/arsnova/service/MotdServiceImpl.java
+++ b/src/main/java/de/thm/arsnova/service/MotdServiceImpl.java
@@ -15,12 +15,13 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.	 If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.service;
 
-import de.thm.arsnova.model.Motd;
-import de.thm.arsnova.model.Room;
-import de.thm.arsnova.persistence.MotdRepository;
-import de.thm.arsnova.web.exceptions.BadRequestException;
+import java.util.ArrayList;
+import java.util.Date;
+import java.util.List;
+import java.util.stream.Collectors;
 import org.springframework.beans.factory.annotation.Qualifier;
 import org.springframework.cache.annotation.CacheEvict;
 import org.springframework.cache.annotation.Cacheable;
@@ -28,10 +29,10 @@ import org.springframework.http.converter.json.MappingJackson2HttpMessageConvert
 import org.springframework.security.access.prepost.PreAuthorize;
 import org.springframework.stereotype.Service;
 
-import java.util.ArrayList;
-import java.util.Date;
-import java.util.List;
-import java.util.stream.Collectors;
+import de.thm.arsnova.model.Motd;
+import de.thm.arsnova.model.Room;
+import de.thm.arsnova.persistence.MotdRepository;
+import de.thm.arsnova.web.exceptions.BadRequestException;
 
 /**
  * Performs all question, interposed question, and answer related operations.
diff --git a/src/main/java/de/thm/arsnova/service/ResponseProviderService.java b/src/main/java/de/thm/arsnova/service/ResponseProviderService.java
index 7b59f4f4c..ce683584e 100644
--- a/src/main/java/de/thm/arsnova/service/ResponseProviderService.java
+++ b/src/main/java/de/thm/arsnova/service/ResponseProviderService.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.service;
 
 import javax.servlet.http.HttpServletResponse;
diff --git a/src/main/java/de/thm/arsnova/service/ResponseProviderServiceImpl.java b/src/main/java/de/thm/arsnova/service/ResponseProviderServiceImpl.java
index 6a6c310f4..c50b8c5fa 100644
--- a/src/main/java/de/thm/arsnova/service/ResponseProviderServiceImpl.java
+++ b/src/main/java/de/thm/arsnova/service/ResponseProviderServiceImpl.java
@@ -15,14 +15,14 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.service;
 
+import javax.servlet.http.HttpServletResponse;
 import org.springframework.context.annotation.Scope;
 import org.springframework.context.annotation.ScopedProxyMode;
 import org.springframework.stereotype.Service;
 
-import javax.servlet.http.HttpServletResponse;
-
 @Service
 @Scope(value = "request", proxyMode = ScopedProxyMode.TARGET_CLASS)
 public class ResponseProviderServiceImpl implements ResponseProviderService {
diff --git a/src/main/java/de/thm/arsnova/service/RoomFindQueryService.java b/src/main/java/de/thm/arsnova/service/RoomFindQueryService.java
index e2fd89cfd..12c6b84f2 100644
--- a/src/main/java/de/thm/arsnova/service/RoomFindQueryService.java
+++ b/src/main/java/de/thm/arsnova/service/RoomFindQueryService.java
@@ -15,17 +15,18 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-package de.thm.arsnova.service;
 
-import de.thm.arsnova.model.FindQuery;
-import de.thm.arsnova.model.Room;
-import de.thm.arsnova.model.UserProfile;
-import org.springframework.stereotype.Service;
+package de.thm.arsnova.service;
 
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Set;
 import java.util.stream.Collectors;
+import org.springframework.stereotype.Service;
+
+import de.thm.arsnova.model.FindQuery;
+import de.thm.arsnova.model.Room;
+import de.thm.arsnova.model.UserProfile;
 
 @Service
 public class RoomFindQueryService implements FindQueryService<Room> {
diff --git a/src/main/java/de/thm/arsnova/service/RoomService.java b/src/main/java/de/thm/arsnova/service/RoomService.java
index d32fbbaec..f8a225a26 100644
--- a/src/main/java/de/thm/arsnova/service/RoomService.java
+++ b/src/main/java/de/thm/arsnova/service/RoomService.java
@@ -15,17 +15,18 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.service;
 
+import java.io.IOException;
+import java.util.List;
+import java.util.UUID;
+
 import de.thm.arsnova.connector.model.Course;
 import de.thm.arsnova.model.Room;
 import de.thm.arsnova.model.transport.ImportExportContainer;
 import de.thm.arsnova.model.transport.ScoreStatistics;
 
-import java.io.IOException;
-import java.util.List;
-import java.util.UUID;
-
 /**
  * The functionality the session service should provide.
  */
diff --git a/src/main/java/de/thm/arsnova/service/RoomServiceImpl.java b/src/main/java/de/thm/arsnova/service/RoomServiceImpl.java
index a58aa2252..177417f79 100644
--- a/src/main/java/de/thm/arsnova/service/RoomServiceImpl.java
+++ b/src/main/java/de/thm/arsnova/service/RoomServiceImpl.java
@@ -15,8 +15,32 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.service;
 
+import java.io.IOException;
+import java.io.Serializable;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.Comparator;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+import java.util.UUID;
+import java.util.stream.Collectors;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.beans.factory.annotation.Qualifier;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.cache.annotation.CacheEvict;
+import org.springframework.cache.annotation.Cacheable;
+import org.springframework.cache.annotation.Caching;
+import org.springframework.http.converter.json.MappingJackson2HttpMessageConverter;
+import org.springframework.scheduling.annotation.Scheduled;
+import org.springframework.security.access.prepost.PreAuthorize;
+import org.springframework.stereotype.Service;
+
 import de.thm.arsnova.connector.client.ConnectorClient;
 import de.thm.arsnova.connector.model.Course;
 import de.thm.arsnova.event.FlipFlashcardsEvent;
@@ -34,29 +58,6 @@ import de.thm.arsnova.service.score.ScoreCalculator;
 import de.thm.arsnova.service.score.ScoreCalculatorFactory;
 import de.thm.arsnova.web.exceptions.ForbiddenException;
 import de.thm.arsnova.web.exceptions.NotFoundException;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.beans.factory.annotation.Qualifier;
-import org.springframework.beans.factory.annotation.Value;
-import org.springframework.cache.annotation.CacheEvict;
-import org.springframework.cache.annotation.Cacheable;
-import org.springframework.cache.annotation.Caching;
-import org.springframework.http.converter.json.MappingJackson2HttpMessageConverter;
-import org.springframework.scheduling.annotation.Scheduled;
-import org.springframework.security.access.prepost.PreAuthorize;
-import org.springframework.stereotype.Service;
-
-import java.io.IOException;
-import java.io.Serializable;
-import java.util.ArrayList;
-import java.util.Collections;
-import java.util.Comparator;
-import java.util.HashSet;
-import java.util.List;
-import java.util.Set;
-import java.util.UUID;
-import java.util.stream.Collectors;
 
 /**
  * Performs all room related operations.
diff --git a/src/main/java/de/thm/arsnova/service/StatisticsService.java b/src/main/java/de/thm/arsnova/service/StatisticsService.java
index fa461a7c3..0a594a9b3 100644
--- a/src/main/java/de/thm/arsnova/service/StatisticsService.java
+++ b/src/main/java/de/thm/arsnova/service/StatisticsService.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.service;
 
 import de.thm.arsnova.model.Statistics;
diff --git a/src/main/java/de/thm/arsnova/service/StatisticsServiceImpl.java b/src/main/java/de/thm/arsnova/service/StatisticsServiceImpl.java
index 6b95c0716..e92a7f576 100644
--- a/src/main/java/de/thm/arsnova/service/StatisticsServiceImpl.java
+++ b/src/main/java/de/thm/arsnova/service/StatisticsServiceImpl.java
@@ -15,14 +15,16 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.service;
 
-import de.thm.arsnova.model.Statistics;
-import de.thm.arsnova.persistence.StatisticsRepository;
 import org.springframework.cache.annotation.Cacheable;
 import org.springframework.scheduling.annotation.Scheduled;
 import org.springframework.stereotype.Service;
 
+import de.thm.arsnova.model.Statistics;
+import de.thm.arsnova.persistence.StatisticsRepository;
+
 /**
  * Performs all statistics related operations. To reduce pressure on the database, data is cached for a fixed amount of
  * time.
diff --git a/src/main/java/de/thm/arsnova/service/StatusService.java b/src/main/java/de/thm/arsnova/service/StatusService.java
index 3ab8b0586..0df938af8 100644
--- a/src/main/java/de/thm/arsnova/service/StatusService.java
+++ b/src/main/java/de/thm/arsnova/service/StatusService.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.service;
 
 import java.util.Map;
diff --git a/src/main/java/de/thm/arsnova/service/StatusServiceImpl.java b/src/main/java/de/thm/arsnova/service/StatusServiceImpl.java
index 94004233e..d165f179b 100644
--- a/src/main/java/de/thm/arsnova/service/StatusServiceImpl.java
+++ b/src/main/java/de/thm/arsnova/service/StatusServiceImpl.java
@@ -15,12 +15,12 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-package de.thm.arsnova.service;
 
-import org.springframework.stereotype.Service;
+package de.thm.arsnova.service;
 
 import java.util.HashMap;
 import java.util.Map;
+import org.springframework.stereotype.Service;
 
 /**
  * Keeps track of maintenance reasons registered by other components. While at least one maintenance reason is active,
diff --git a/src/main/java/de/thm/arsnova/service/TimerService.java b/src/main/java/de/thm/arsnova/service/TimerService.java
index 972de6ea8..853705d58 100644
--- a/src/main/java/de/thm/arsnova/service/TimerService.java
+++ b/src/main/java/de/thm/arsnova/service/TimerService.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.service;
 
 public interface TimerService {
diff --git a/src/main/java/de/thm/arsnova/service/TimerServiceImpl.java b/src/main/java/de/thm/arsnova/service/TimerServiceImpl.java
index 5c18e1924..50fcbfbbf 100644
--- a/src/main/java/de/thm/arsnova/service/TimerServiceImpl.java
+++ b/src/main/java/de/thm/arsnova/service/TimerServiceImpl.java
@@ -15,20 +15,21 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-package de.thm.arsnova.service;
 
-import de.thm.arsnova.model.Content;
-import de.thm.arsnova.model.Room;
-import de.thm.arsnova.persistence.AnswerRepository;
-import de.thm.arsnova.security.User;
-import org.springframework.cache.annotation.CacheEvict;
-import org.springframework.security.access.prepost.PreAuthorize;
-import org.springframework.stereotype.Service;
+package de.thm.arsnova.service;
 
 import java.util.Date;
 import java.util.HashMap;
 import java.util.Timer;
 import java.util.TimerTask;
+import org.springframework.cache.annotation.CacheEvict;
+import org.springframework.security.access.prepost.PreAuthorize;
+import org.springframework.stereotype.Service;
+
+import de.thm.arsnova.model.Content;
+import de.thm.arsnova.model.Room;
+import de.thm.arsnova.persistence.AnswerRepository;
+import de.thm.arsnova.security.User;
 
 @Service
 public class TimerServiceImpl implements TimerService {
diff --git a/src/main/java/de/thm/arsnova/service/UserFindQueryService.java b/src/main/java/de/thm/arsnova/service/UserFindQueryService.java
index a2d5511ac..6e4d5f23b 100644
--- a/src/main/java/de/thm/arsnova/service/UserFindQueryService.java
+++ b/src/main/java/de/thm/arsnova/service/UserFindQueryService.java
@@ -15,15 +15,16 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-package de.thm.arsnova.service;
 
-import de.thm.arsnova.model.FindQuery;
-import de.thm.arsnova.model.UserProfile;
-import org.springframework.stereotype.Service;
+package de.thm.arsnova.service;
 
 import java.util.HashSet;
 import java.util.List;
 import java.util.Set;
+import org.springframework.stereotype.Service;
+
+import de.thm.arsnova.model.FindQuery;
+import de.thm.arsnova.model.UserProfile;
 
 @Service
 public class UserFindQueryService implements FindQueryService<UserProfile> {
diff --git a/src/main/java/de/thm/arsnova/service/UserService.java b/src/main/java/de/thm/arsnova/service/UserService.java
index 3ef754be9..fd09780c5 100644
--- a/src/main/java/de/thm/arsnova/service/UserService.java
+++ b/src/main/java/de/thm/arsnova/service/UserService.java
@@ -15,20 +15,21 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-package de.thm.arsnova.service;
 
-import de.thm.arsnova.model.Room;
-import de.thm.arsnova.model.UserProfile;
-import de.thm.arsnova.security.User;
-import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
-import org.springframework.security.core.GrantedAuthority;
-import org.springframework.security.core.userdetails.UsernameNotFoundException;
+package de.thm.arsnova.service;
 
 import java.util.Collection;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
 import java.util.UUID;
+import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
+import org.springframework.security.core.GrantedAuthority;
+import org.springframework.security.core.userdetails.UsernameNotFoundException;
+
+import de.thm.arsnova.model.Room;
+import de.thm.arsnova.model.UserProfile;
+import de.thm.arsnova.security.User;
 
 /**
  * The functionality the user service should provide.
diff --git a/src/main/java/de/thm/arsnova/service/UserServiceImpl.java b/src/main/java/de/thm/arsnova/service/UserServiceImpl.java
index c0b6f08b6..7796fb5ac 100644
--- a/src/main/java/de/thm/arsnova/service/UserServiceImpl.java
+++ b/src/main/java/de/thm/arsnova/service/UserServiceImpl.java
@@ -15,20 +15,28 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.service;
 
 import com.codahale.metrics.annotation.Gauge;
-import de.thm.arsnova.model.ClientAuthentication;
-import de.thm.arsnova.model.Room;
-import de.thm.arsnova.model.UserProfile;
-import de.thm.arsnova.persistence.UserRepository;
-import de.thm.arsnova.security.GuestUserDetailsService;
-import de.thm.arsnova.security.User;
-import de.thm.arsnova.security.jwt.JwtService;
-import de.thm.arsnova.security.jwt.JwtToken;
-import de.thm.arsnova.web.exceptions.BadRequestException;
-import de.thm.arsnova.web.exceptions.NotFoundException;
-import de.thm.arsnova.web.exceptions.UnauthorizedException;
+import java.io.IOException;
+import java.text.MessageFormat;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.Date;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.Set;
+import java.util.UUID;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.regex.Pattern;
+import javax.annotation.PreDestroy;
+import javax.mail.MessagingException;
+import javax.mail.internet.MimeMessage;
 import org.apache.commons.lang.RandomStringUtils;
 import org.apache.commons.lang.StringUtils;
 import org.slf4j.Logger;
@@ -61,15 +69,17 @@ import org.springframework.transaction.annotation.Transactional;
 import org.springframework.web.util.UriUtils;
 import org.stagemonitor.core.metrics.MonitorGauges;
 
-import javax.annotation.PreDestroy;
-import javax.mail.MessagingException;
-import javax.mail.internet.MimeMessage;
-import java.io.IOException;
-import java.text.MessageFormat;
-import java.util.*;
-import java.util.Map.Entry;
-import java.util.concurrent.ConcurrentHashMap;
-import java.util.regex.Pattern;
+import de.thm.arsnova.model.ClientAuthentication;
+import de.thm.arsnova.model.Room;
+import de.thm.arsnova.model.UserProfile;
+import de.thm.arsnova.persistence.UserRepository;
+import de.thm.arsnova.security.GuestUserDetailsService;
+import de.thm.arsnova.security.User;
+import de.thm.arsnova.security.jwt.JwtService;
+import de.thm.arsnova.security.jwt.JwtToken;
+import de.thm.arsnova.web.exceptions.BadRequestException;
+import de.thm.arsnova.web.exceptions.NotFoundException;
+import de.thm.arsnova.web.exceptions.UnauthorizedException;
 
 /**
  * Performs all user related operations.
diff --git a/src/main/java/de/thm/arsnova/service/package-info.java b/src/main/java/de/thm/arsnova/service/package-info.java
index dfa2ac665..aadfa1022 100644
--- a/src/main/java/de/thm/arsnova/service/package-info.java
+++ b/src/main/java/de/thm/arsnova/service/package-info.java
@@ -1,4 +1,5 @@
 /**
  * Classes and interfaces for the service layer
  */
+
 package de.thm.arsnova.service;
diff --git a/src/main/java/de/thm/arsnova/service/score/QuestionBasedScoreCalculator.java b/src/main/java/de/thm/arsnova/service/score/QuestionBasedScoreCalculator.java
index 797445dbd..6188ce98f 100644
--- a/src/main/java/de/thm/arsnova/service/score/QuestionBasedScoreCalculator.java
+++ b/src/main/java/de/thm/arsnova/service/score/QuestionBasedScoreCalculator.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.service.score;
 
 import de.thm.arsnova.model.transport.ScoreStatistics;
diff --git a/src/main/java/de/thm/arsnova/service/score/QuestionScore.java b/src/main/java/de/thm/arsnova/service/score/QuestionScore.java
index 344092347..62d01d956 100644
--- a/src/main/java/de/thm/arsnova/service/score/QuestionScore.java
+++ b/src/main/java/de/thm/arsnova/service/score/QuestionScore.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.service.score;
 
 import java.util.ArrayList;
diff --git a/src/main/java/de/thm/arsnova/service/score/Score.java b/src/main/java/de/thm/arsnova/service/score/Score.java
index a32565b0e..99c7bd684 100644
--- a/src/main/java/de/thm/arsnova/service/score/Score.java
+++ b/src/main/java/de/thm/arsnova/service/score/Score.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.service.score;
 
 import java.util.HashMap;
diff --git a/src/main/java/de/thm/arsnova/service/score/ScoreBasedScoreCalculator.java b/src/main/java/de/thm/arsnova/service/score/ScoreBasedScoreCalculator.java
index cfd7a5dc2..f1ed464f5 100644
--- a/src/main/java/de/thm/arsnova/service/score/ScoreBasedScoreCalculator.java
+++ b/src/main/java/de/thm/arsnova/service/score/ScoreBasedScoreCalculator.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.service.score;
 
 import de.thm.arsnova.model.transport.ScoreStatistics;
diff --git a/src/main/java/de/thm/arsnova/service/score/ScoreCalculator.java b/src/main/java/de/thm/arsnova/service/score/ScoreCalculator.java
index f835fd1af..0602be51c 100644
--- a/src/main/java/de/thm/arsnova/service/score/ScoreCalculator.java
+++ b/src/main/java/de/thm/arsnova/service/score/ScoreCalculator.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.service.score;
 
 import de.thm.arsnova.model.Room;
diff --git a/src/main/java/de/thm/arsnova/service/score/ScoreCalculatorFactory.java b/src/main/java/de/thm/arsnova/service/score/ScoreCalculatorFactory.java
index 8af0aa2e4..01c7de0d1 100644
--- a/src/main/java/de/thm/arsnova/service/score/ScoreCalculatorFactory.java
+++ b/src/main/java/de/thm/arsnova/service/score/ScoreCalculatorFactory.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.service.score;
 
 /**
diff --git a/src/main/java/de/thm/arsnova/service/score/ScoreCalculatorFactoryImpl.java b/src/main/java/de/thm/arsnova/service/score/ScoreCalculatorFactoryImpl.java
index fa2a595e8..c108a0319 100644
--- a/src/main/java/de/thm/arsnova/service/score/ScoreCalculatorFactoryImpl.java
+++ b/src/main/java/de/thm/arsnova/service/score/ScoreCalculatorFactoryImpl.java
@@ -15,8 +15,16 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.service.score;
 
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.cache.annotation.CacheEvict;
+import org.springframework.context.ApplicationEventPublisher;
+import org.springframework.context.ApplicationEventPublisherAware;
+import org.springframework.context.event.EventListener;
+import org.springframework.stereotype.Component;
+
 import de.thm.arsnova.event.AfterCreationEvent;
 import de.thm.arsnova.event.AfterDeletionEvent;
 import de.thm.arsnova.event.ChangeScoreEvent;
@@ -24,12 +32,6 @@ import de.thm.arsnova.event.StateChangeEvent;
 import de.thm.arsnova.model.Answer;
 import de.thm.arsnova.model.Content;
 import de.thm.arsnova.persistence.SessionStatisticsRepository;
-import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.cache.annotation.CacheEvict;
-import org.springframework.context.ApplicationEventPublisher;
-import org.springframework.context.ApplicationEventPublisherAware;
-import org.springframework.context.event.EventListener;
-import org.springframework.stereotype.Component;
 
 /**
  * Creates a score calculator implementation.
diff --git a/src/main/java/de/thm/arsnova/service/score/UserScore.java b/src/main/java/de/thm/arsnova/service/score/UserScore.java
index 444568006..175b862b0 100644
--- a/src/main/java/de/thm/arsnova/service/score/UserScore.java
+++ b/src/main/java/de/thm/arsnova/service/score/UserScore.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.service.score;
 
 /**
diff --git a/src/main/java/de/thm/arsnova/service/score/VariantScoreCalculator.java b/src/main/java/de/thm/arsnova/service/score/VariantScoreCalculator.java
index a4ad876db..990a95489 100644
--- a/src/main/java/de/thm/arsnova/service/score/VariantScoreCalculator.java
+++ b/src/main/java/de/thm/arsnova/service/score/VariantScoreCalculator.java
@@ -15,12 +15,14 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.service.score;
 
+import org.springframework.cache.annotation.Cacheable;
+
 import de.thm.arsnova.model.Room;
 import de.thm.arsnova.model.transport.ScoreStatistics;
 import de.thm.arsnova.persistence.SessionStatisticsRepository;
-import org.springframework.cache.annotation.Cacheable;
 
 /**
  * Base class for the score feature that allows filtering on the question variant.
diff --git a/src/main/java/de/thm/arsnova/util/ImageUtils.java b/src/main/java/de/thm/arsnova/util/ImageUtils.java
index 79155fbea..8cccb5409 100644
--- a/src/main/java/de/thm/arsnova/util/ImageUtils.java
+++ b/src/main/java/de/thm/arsnova/util/ImageUtils.java
@@ -15,23 +15,24 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-package de.thm.arsnova.util;
 
-import de.thm.arsnova.model.migration.v2.Answer;
-import org.apache.commons.codec.binary.Base64;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-import org.springframework.beans.factory.annotation.Value;
-import org.springframework.stereotype.Component;
+package de.thm.arsnova.util;
 
-import javax.imageio.ImageIO;
-import java.awt.*;
+import java.awt.Graphics2D;
 import java.awt.image.BufferedImage;
 import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
 import java.net.URL;
+import javax.imageio.ImageIO;
+import org.apache.commons.codec.binary.Base64;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.stereotype.Component;
+
+import de.thm.arsnova.model.migration.v2.Answer;
 
 /**
  * Util class for image operations.
diff --git a/src/main/java/de/thm/arsnova/util/PaginationListDecorator.java b/src/main/java/de/thm/arsnova/util/PaginationListDecorator.java
index 05901fd71..e630c1cf7 100644
--- a/src/main/java/de/thm/arsnova/util/PaginationListDecorator.java
+++ b/src/main/java/de/thm/arsnova/util/PaginationListDecorator.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.util;
 
 import java.util.Collection;
diff --git a/src/main/java/de/thm/arsnova/web/CacheControl.java b/src/main/java/de/thm/arsnova/web/CacheControl.java
index bcbadb5ee..4fad63ee2 100644
--- a/src/main/java/de/thm/arsnova/web/CacheControl.java
+++ b/src/main/java/de/thm/arsnova/web/CacheControl.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.web;
 
 import java.lang.annotation.ElementType;
diff --git a/src/main/java/de/thm/arsnova/web/CacheControlInterceptorHandler.java b/src/main/java/de/thm/arsnova/web/CacheControlInterceptorHandler.java
index 0a10cabc2..d362ae20d 100644
--- a/src/main/java/de/thm/arsnova/web/CacheControlInterceptorHandler.java
+++ b/src/main/java/de/thm/arsnova/web/CacheControlInterceptorHandler.java
@@ -15,15 +15,15 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.web;
 
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
 import org.springframework.stereotype.Component;
 import org.springframework.web.method.HandlerMethod;
 import org.springframework.web.servlet.handler.HandlerInterceptorAdapter;
 
-import javax.servlet.http.HttpServletRequest;
-import javax.servlet.http.HttpServletResponse;
-
 /**
  * Adds caching headers to a HTTP request based on {@link CacheControl} annotation.
  */
diff --git a/src/main/java/de/thm/arsnova/web/CorsFilter.java b/src/main/java/de/thm/arsnova/web/CorsFilter.java
index f51d96a47..f5aa3a320 100644
--- a/src/main/java/de/thm/arsnova/web/CorsFilter.java
+++ b/src/main/java/de/thm/arsnova/web/CorsFilter.java
@@ -15,15 +15,15 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.web;
 
+import java.util.List;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.web.cors.CorsConfiguration;
 import org.springframework.web.cors.UrlBasedCorsConfigurationSource;
 
-import java.util.List;
-
 public class CorsFilter extends org.springframework.web.filter.CorsFilter {
 	private static final String TOKEN_HEADER_NAME = "Arsnova-Auth-Token";
 	private final Logger logger = LoggerFactory.getLogger(CorsFilter.class);
diff --git a/src/main/java/de/thm/arsnova/web/DeprecatedApi.java b/src/main/java/de/thm/arsnova/web/DeprecatedApi.java
index 784f968db..ad671a7fe 100644
--- a/src/main/java/de/thm/arsnova/web/DeprecatedApi.java
+++ b/src/main/java/de/thm/arsnova/web/DeprecatedApi.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.web;
 
 import java.lang.annotation.ElementType;
diff --git a/src/main/java/de/thm/arsnova/web/DeprecatedApiInterceptorHandler.java b/src/main/java/de/thm/arsnova/web/DeprecatedApiInterceptorHandler.java
index f81f239d3..321a7308f 100644
--- a/src/main/java/de/thm/arsnova/web/DeprecatedApiInterceptorHandler.java
+++ b/src/main/java/de/thm/arsnova/web/DeprecatedApiInterceptorHandler.java
@@ -15,15 +15,15 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.web;
 
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
 import org.springframework.stereotype.Component;
 import org.springframework.web.method.HandlerMethod;
 import org.springframework.web.servlet.handler.HandlerInterceptorAdapter;
 
-import javax.servlet.http.HttpServletRequest;
-import javax.servlet.http.HttpServletResponse;
-
 /**
  * Adds a "deprecated" header to any HTTP response that is served by a controller method with the {@link DeprecatedApi}
  * annotation.
diff --git a/src/main/java/de/thm/arsnova/web/InternalEntityAspect.java b/src/main/java/de/thm/arsnova/web/InternalEntityAspect.java
index 54e4142a6..c2d29fb8a 100644
--- a/src/main/java/de/thm/arsnova/web/InternalEntityAspect.java
+++ b/src/main/java/de/thm/arsnova/web/InternalEntityAspect.java
@@ -15,14 +15,16 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.web;
 
-import de.thm.arsnova.model.Entity;
 import org.aspectj.lang.annotation.AfterReturning;
 import org.aspectj.lang.annotation.Aspect;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import de.thm.arsnova.model.Entity;
+
 /**
  * This aspect ensures that entities marked for internal use are not serialized for the public API.
  *
diff --git a/src/main/java/de/thm/arsnova/web/MaintenanceModeFilter.java b/src/main/java/de/thm/arsnova/web/MaintenanceModeFilter.java
index 7577faa34..58286907b 100644
--- a/src/main/java/de/thm/arsnova/web/MaintenanceModeFilter.java
+++ b/src/main/java/de/thm/arsnova/web/MaintenanceModeFilter.java
@@ -15,17 +15,18 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-package de.thm.arsnova.web;
 
-import de.thm.arsnova.service.StatusService;
-import org.springframework.stereotype.Component;
-import org.springframework.web.filter.OncePerRequestFilter;
+package de.thm.arsnova.web;
 
+import java.io.IOException;
 import javax.servlet.FilterChain;
 import javax.servlet.ServletException;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
-import java.io.IOException;
+import org.springframework.stereotype.Component;
+import org.springframework.web.filter.OncePerRequestFilter;
+
+import de.thm.arsnova.service.StatusService;
 
 /**
  * Blocks API requests while maintenance reasons are active.
diff --git a/src/main/java/de/thm/arsnova/web/Pagination.java b/src/main/java/de/thm/arsnova/web/Pagination.java
index e27194bfe..7865928d3 100644
--- a/src/main/java/de/thm/arsnova/web/Pagination.java
+++ b/src/main/java/de/thm/arsnova/web/Pagination.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.web;
 
 import java.lang.annotation.Documented;
diff --git a/src/main/java/de/thm/arsnova/web/PathApiVersionContentNegotiationStrategy.java b/src/main/java/de/thm/arsnova/web/PathApiVersionContentNegotiationStrategy.java
index 3bacee85d..699a79f6c 100644
--- a/src/main/java/de/thm/arsnova/web/PathApiVersionContentNegotiationStrategy.java
+++ b/src/main/java/de/thm/arsnova/web/PathApiVersionContentNegotiationStrategy.java
@@ -15,10 +15,13 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.web;
 
-import de.thm.arsnova.config.AppConfig;
-import de.thm.arsnova.controller.AbstractEntityController;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+import javax.servlet.http.HttpServletRequest;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.http.HttpHeaders;
@@ -27,10 +30,8 @@ import org.springframework.web.HttpMediaTypeNotAcceptableException;
 import org.springframework.web.accept.ContentNegotiationStrategy;
 import org.springframework.web.context.request.NativeWebRequest;
 
-import javax.servlet.http.HttpServletRequest;
-import java.util.ArrayList;
-import java.util.Arrays;
-import java.util.List;
+import de.thm.arsnova.config.AppConfig;
+import de.thm.arsnova.controller.AbstractEntityController;
 
 /**
  * This {@link ContentNegotiationStrategy} selects the media type based on request path. It allows to set the correct
diff --git a/src/main/java/de/thm/arsnova/web/RangeAspect.java b/src/main/java/de/thm/arsnova/web/RangeAspect.java
index 87e2c14dc..913606164 100644
--- a/src/main/java/de/thm/arsnova/web/RangeAspect.java
+++ b/src/main/java/de/thm/arsnova/web/RangeAspect.java
@@ -15,11 +15,14 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.web;
 
-import de.thm.arsnova.controller.PaginationController;
-import de.thm.arsnova.service.ResponseProviderService;
-import de.thm.arsnova.util.PaginationListDecorator;
+import java.util.List;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
 import org.aspectj.lang.ProceedingJoinPoint;
 import org.aspectj.lang.annotation.Around;
 import org.aspectj.lang.annotation.Aspect;
@@ -28,11 +31,9 @@ import org.slf4j.LoggerFactory;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.beans.factory.annotation.Configurable;
 
-import javax.servlet.http.HttpServletRequest;
-import javax.servlet.http.HttpServletResponse;
-import java.util.List;
-import java.util.regex.Matcher;
-import java.util.regex.Pattern;
+import de.thm.arsnova.controller.PaginationController;
+import de.thm.arsnova.service.ResponseProviderService;
+import de.thm.arsnova.util.PaginationListDecorator;
 
 /**
  * An aspect which parses requests for pagination parameters in a "Range" header and adds a "Content-Range" header to
diff --git a/src/main/java/de/thm/arsnova/web/ResponseInterceptorHandler.java b/src/main/java/de/thm/arsnova/web/ResponseInterceptorHandler.java
index 9d4f2cb3d..24f1311c0 100644
--- a/src/main/java/de/thm/arsnova/web/ResponseInterceptorHandler.java
+++ b/src/main/java/de/thm/arsnova/web/ResponseInterceptorHandler.java
@@ -15,15 +15,16 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.web;
 
-import de.thm.arsnova.service.ResponseProviderService;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.stereotype.Component;
 import org.springframework.web.servlet.handler.HandlerInterceptorAdapter;
 
-import javax.servlet.http.HttpServletRequest;
-import javax.servlet.http.HttpServletResponse;
+import de.thm.arsnova.service.ResponseProviderService;
 
 /**
  *  Injects a {@link HttpServletResponse} into {@link ResponseProviderService} to allow access to it outside of
diff --git a/src/main/java/de/thm/arsnova/web/V2ContentTypeOverrideFilter.java b/src/main/java/de/thm/arsnova/web/V2ContentTypeOverrideFilter.java
index f06569027..99c09a24e 100644
--- a/src/main/java/de/thm/arsnova/web/V2ContentTypeOverrideFilter.java
+++ b/src/main/java/de/thm/arsnova/web/V2ContentTypeOverrideFilter.java
@@ -15,9 +15,19 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.web;
 
-import de.thm.arsnova.config.AppConfig;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.Enumeration;
+import java.util.List;
+import javax.servlet.FilterChain;
+import javax.servlet.ServletException;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletRequestWrapper;
+import javax.servlet.http.HttpServletResponse;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.http.HttpHeaders;
@@ -25,16 +35,7 @@ import org.springframework.http.MediaType;
 import org.springframework.stereotype.Component;
 import org.springframework.web.filter.OncePerRequestFilter;
 
-import javax.servlet.FilterChain;
-import javax.servlet.ServletException;
-import javax.servlet.http.HttpServletRequest;
-import javax.servlet.http.HttpServletRequestWrapper;
-import javax.servlet.http.HttpServletResponse;
-import java.io.IOException;
-import java.util.ArrayList;
-import java.util.Collections;
-import java.util.Enumeration;
-import java.util.List;
+import de.thm.arsnova.config.AppConfig;
 
 /**
  * This {@link javax.servlet.Filter} overrides the Content-Type for JSON data sent by the client with the ARSnova API v2
diff --git a/src/main/java/de/thm/arsnova/web/exceptions/package-info.java b/src/main/java/de/thm/arsnova/web/exceptions/package-info.java
index 03df89db5..3a24af121 100644
--- a/src/main/java/de/thm/arsnova/web/exceptions/package-info.java
+++ b/src/main/java/de/thm/arsnova/web/exceptions/package-info.java
@@ -1,4 +1,5 @@
 /**
  * Contains exceptions used to return HTTP status codes
  */
+
 package de.thm.arsnova.web.exceptions;
diff --git a/src/main/java/de/thm/arsnova/web/package-info.java b/src/main/java/de/thm/arsnova/web/package-info.java
index c22db2a22..92bdc3752 100644
--- a/src/main/java/de/thm/arsnova/web/package-info.java
+++ b/src/main/java/de/thm/arsnova/web/package-info.java
@@ -1,4 +1,5 @@
 /**
  * Contains HTTP related classes and interfaces
  */
+
 package de.thm.arsnova.web;
diff --git a/src/main/java/de/thm/arsnova/websocket/ArsnovaSocketioServer.java b/src/main/java/de/thm/arsnova/websocket/ArsnovaSocketioServer.java
index b9d773ac3..64c30a521 100644
--- a/src/main/java/de/thm/arsnova/websocket/ArsnovaSocketioServer.java
+++ b/src/main/java/de/thm/arsnova/websocket/ArsnovaSocketioServer.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.websocket;
 
 /**
diff --git a/src/main/java/de/thm/arsnova/websocket/ArsnovaSocketioServerImpl.java b/src/main/java/de/thm/arsnova/websocket/ArsnovaSocketioServerImpl.java
index 7211c9450..46c4cd369 100644
--- a/src/main/java/de/thm/arsnova/websocket/ArsnovaSocketioServerImpl.java
+++ b/src/main/java/de/thm/arsnova/websocket/ArsnovaSocketioServerImpl.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.websocket;
 
 import com.codahale.metrics.annotation.Timed;
@@ -28,6 +29,27 @@ import com.corundumstudio.socketio.listener.DataListener;
 import com.corundumstudio.socketio.listener.DisconnectListener;
 import com.corundumstudio.socketio.protocol.Packet;
 import com.corundumstudio.socketio.protocol.PacketType;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.Set;
+import java.util.UUID;
+import javax.annotation.PreDestroy;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.beans.factory.annotation.Required;
+import org.springframework.context.event.EventListener;
+import org.springframework.scheduling.annotation.Async;
+import org.springframework.stereotype.Component;
+
 import de.thm.arsnova.event.AfterCreationEvent;
 import de.thm.arsnova.event.AfterDeletionEvent;
 import de.thm.arsnova.event.ChangeScoreEvent;
@@ -51,27 +73,6 @@ import de.thm.arsnova.web.exceptions.UnauthorizedException;
 import de.thm.arsnova.websocket.message.Content;
 import de.thm.arsnova.websocket.message.Feedback;
 import de.thm.arsnova.websocket.message.Room;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.beans.factory.annotation.Required;
-import org.springframework.context.event.EventListener;
-import org.springframework.scheduling.annotation.Async;
-import org.springframework.stereotype.Component;
-
-import javax.annotation.PreDestroy;
-import java.io.FileInputStream;
-import java.io.FileNotFoundException;
-import java.io.IOException;
-import java.io.InputStream;
-import java.util.ArrayList;
-import java.util.Collections;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
-import java.util.Map.Entry;
-import java.util.Set;
-import java.util.UUID;
 
 /**
  * Web socket implementation based on Socket.io.
diff --git a/src/main/java/de/thm/arsnova/websocket/WebsocketAuthenticationAspect.java b/src/main/java/de/thm/arsnova/websocket/WebsocketAuthenticationAspect.java
index 6b0abc8bb..6b045c981 100644
--- a/src/main/java/de/thm/arsnova/websocket/WebsocketAuthenticationAspect.java
+++ b/src/main/java/de/thm/arsnova/websocket/WebsocketAuthenticationAspect.java
@@ -15,11 +15,13 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.websocket;
 
 import com.corundumstudio.socketio.SocketIOClient;
-import de.thm.arsnova.security.User;
-import de.thm.arsnova.service.UserService;
+import java.util.HashSet;
+import java.util.Set;
+import java.util.UUID;
 import org.aspectj.lang.ProceedingJoinPoint;
 import org.aspectj.lang.annotation.Around;
 import org.aspectj.lang.annotation.Aspect;
@@ -35,9 +37,8 @@ import org.springframework.security.core.authority.SimpleGrantedAuthority;
 import org.springframework.security.core.context.SecurityContext;
 import org.springframework.security.core.context.SecurityContextHolder;
 
-import java.util.HashSet;
-import java.util.Set;
-import java.util.UUID;
+import de.thm.arsnova.security.User;
+import de.thm.arsnova.service.UserService;
 
 /**
  * This aspect populates the SecurityContextHolder of Spring Security when data are received via WebSockets.
diff --git a/src/main/java/de/thm/arsnova/websocket/handler/AuthChannelInterceptorAdapter.java b/src/main/java/de/thm/arsnova/websocket/handler/AuthChannelInterceptorAdapter.java
index 3e06953af..4318789f9 100644
--- a/src/main/java/de/thm/arsnova/websocket/handler/AuthChannelInterceptorAdapter.java
+++ b/src/main/java/de/thm/arsnova/websocket/handler/AuthChannelInterceptorAdapter.java
@@ -1,7 +1,7 @@
 package de.thm.arsnova.websocket.handler;
 
-import de.thm.arsnova.security.User;
-import de.thm.arsnova.service.UserService;
+import java.util.List;
+import org.checkerframework.checker.nullness.qual.Nullable;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.beans.factory.annotation.Autowired;
@@ -13,8 +13,8 @@ import org.springframework.messaging.support.ChannelInterceptor;
 import org.springframework.messaging.support.MessageBuilder;
 import org.springframework.stereotype.Component;
 
-import org.checkerframework.checker.nullness.qual.Nullable;
-import java.util.List;
+import de.thm.arsnova.security.User;
+import de.thm.arsnova.service.UserService;
 
 @Component
 public class AuthChannelInterceptorAdapter implements ChannelInterceptor {
diff --git a/src/main/java/de/thm/arsnova/websocket/handler/FeedbackCommandHandler.java b/src/main/java/de/thm/arsnova/websocket/handler/FeedbackCommandHandler.java
index 19c8de57f..e3e6f430c 100644
--- a/src/main/java/de/thm/arsnova/websocket/handler/FeedbackCommandHandler.java
+++ b/src/main/java/de/thm/arsnova/websocket/handler/FeedbackCommandHandler.java
@@ -1,14 +1,14 @@
 package de.thm.arsnova.websocket.handler;
 
-import de.thm.arsnova.websocket.message.CreateFeedback;
-import de.thm.arsnova.websocket.message.FeedbackChanged;
-import de.thm.arsnova.websocket.message.FeedbackChangedPayload;
-import de.thm.arsnova.websocket.message.GetFeedback;
+import java.util.HashMap;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.messaging.simp.SimpMessagingTemplate;
 import org.springframework.stereotype.Component;
 
-import java.util.HashMap;
+import de.thm.arsnova.websocket.message.CreateFeedback;
+import de.thm.arsnova.websocket.message.FeedbackChanged;
+import de.thm.arsnova.websocket.message.FeedbackChangedPayload;
+import de.thm.arsnova.websocket.message.GetFeedback;
 
 @Component
 public class FeedbackCommandHandler {
diff --git a/src/main/java/de/thm/arsnova/websocket/handler/FeedbackHandler.java b/src/main/java/de/thm/arsnova/websocket/handler/FeedbackHandler.java
index 2bb2943a9..50308d6ff 100644
--- a/src/main/java/de/thm/arsnova/websocket/handler/FeedbackHandler.java
+++ b/src/main/java/de/thm/arsnova/websocket/handler/FeedbackHandler.java
@@ -1,12 +1,13 @@
 package de.thm.arsnova.websocket.handler;
 
-import de.thm.arsnova.websocket.message.CreateFeedback;
-import de.thm.arsnova.websocket.message.GetFeedback;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.messaging.handler.annotation.DestinationVariable;
 import org.springframework.messaging.handler.annotation.MessageMapping;
 import org.springframework.stereotype.Controller;
 
+import de.thm.arsnova.websocket.message.CreateFeedback;
+import de.thm.arsnova.websocket.message.GetFeedback;
+
 @Controller
 public class FeedbackHandler {
 	private final FeedbackCommandHandler commandHandler;
diff --git a/src/main/java/de/thm/arsnova/websocket/message/Content.java b/src/main/java/de/thm/arsnova/websocket/message/Content.java
index 86eb37a68..5ccc1c236 100644
--- a/src/main/java/de/thm/arsnova/websocket/message/Content.java
+++ b/src/main/java/de/thm/arsnova/websocket/message/Content.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.websocket.message;
 
 /**
diff --git a/src/main/java/de/thm/arsnova/websocket/message/Feedback.java b/src/main/java/de/thm/arsnova/websocket/message/Feedback.java
index 0059ef5a1..e18789dc4 100644
--- a/src/main/java/de/thm/arsnova/websocket/message/Feedback.java
+++ b/src/main/java/de/thm/arsnova/websocket/message/Feedback.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.websocket.message;
 
 /**
diff --git a/src/main/java/de/thm/arsnova/websocket/message/Room.java b/src/main/java/de/thm/arsnova/websocket/message/Room.java
index a55734625..25de1d48b 100644
--- a/src/main/java/de/thm/arsnova/websocket/message/Room.java
+++ b/src/main/java/de/thm/arsnova/websocket/message/Room.java
@@ -15,6 +15,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.websocket.message;
 
 /**
diff --git a/src/main/java/de/thm/arsnova/websocket/message/package-info.java b/src/main/java/de/thm/arsnova/websocket/message/package-info.java
index 0af4ab419..3f488a34d 100644
--- a/src/main/java/de/thm/arsnova/websocket/message/package-info.java
+++ b/src/main/java/de/thm/arsnova/websocket/message/package-info.java
@@ -1,4 +1,5 @@
 /**
  * Contains classes that are used as web socket messages
  */
+
 package de.thm.arsnova.websocket.message;
diff --git a/src/main/java/de/thm/arsnova/websocket/package-info.java b/src/main/java/de/thm/arsnova/websocket/package-info.java
index 3fd6e43c0..febedc2d5 100644
--- a/src/main/java/de/thm/arsnova/websocket/package-info.java
+++ b/src/main/java/de/thm/arsnova/websocket/package-info.java
@@ -1,4 +1,5 @@
 /**
  * Classes and interfaces for communication over web sockets
  */
+
 package de.thm.arsnova.websocket;
diff --git a/src/test/java/de/thm/arsnova/config/AppConfigTest.java b/src/test/java/de/thm/arsnova/config/AppConfigTest.java
index fc210c35a..0d7062cd1 100644
--- a/src/test/java/de/thm/arsnova/config/AppConfigTest.java
+++ b/src/test/java/de/thm/arsnova/config/AppConfigTest.java
@@ -15,9 +15,11 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.config;
 
-import de.thm.arsnova.connector.client.ConnectorClient;
+import static org.junit.Assert.assertNull;
+
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.springframework.beans.factory.annotation.Autowired;
@@ -29,10 +31,10 @@ import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
 import org.springframework.test.context.web.WebAppConfiguration;
 
 import java.util.Arrays;
+import de.thm.arsnova.connector.client.ConnectorClient;
 import java.util.List;
 
 import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertNull;
 
 @RunWith(SpringJUnit4ClassRunner.class)
 @WebAppConfiguration
diff --git a/src/test/java/de/thm/arsnova/config/TestAppConfig.java b/src/test/java/de/thm/arsnova/config/TestAppConfig.java
index 036464233..6fdff03e3 100644
--- a/src/test/java/de/thm/arsnova/config/TestAppConfig.java
+++ b/src/test/java/de/thm/arsnova/config/TestAppConfig.java
@@ -15,14 +15,11 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.config;
 
 import de.thm.arsnova.controller.JsonViewControllerAdviceTest;
-import de.thm.arsnova.persistence.UserRepository;
 import de.thm.arsnova.service.EntityService;
-import de.thm.arsnova.service.StubUserService;
-import de.thm.arsnova.websocket.ArsnovaSocketioServer;
-import de.thm.arsnova.websocket.ArsnovaSocketioServerImpl;
 import org.mockito.Mockito;
 import org.springframework.beans.factory.annotation.Qualifier;
 import org.springframework.beans.factory.annotation.Value;
@@ -44,6 +41,11 @@ import org.springframework.test.context.ContextConfiguration;
 import org.springframework.test.context.support.AnnotationConfigContextLoader;
 import org.springframework.web.servlet.config.annotation.EnableWebMvc;
 
+import de.thm.arsnova.persistence.UserRepository;
+import de.thm.arsnova.service.StubUserService;
+import de.thm.arsnova.websocket.ArsnovaSocketioServer;
+import de.thm.arsnova.websocket.ArsnovaSocketioServerImpl;
+
 @ComponentScan({
 		"de.thm.arsnova.aop",
 		"de.thm.arsnova.cache",
diff --git a/src/test/java/de/thm/arsnova/config/TestPersistanceConfig.java b/src/test/java/de/thm/arsnova/config/TestPersistanceConfig.java
index 0198395ee..92e5af312 100644
--- a/src/test/java/de/thm/arsnova/config/TestPersistanceConfig.java
+++ b/src/test/java/de/thm/arsnova/config/TestPersistanceConfig.java
@@ -15,14 +15,25 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.config;
 
-import de.thm.arsnova.persistence.*;
 import org.mockito.Mockito;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.context.annotation.Profile;
 
+import de.thm.arsnova.persistence.AnswerRepository;
+import de.thm.arsnova.persistence.AttachmentRepository;
+import de.thm.arsnova.persistence.CommentRepository;
+import de.thm.arsnova.persistence.ContentRepository;
+import de.thm.arsnova.persistence.LogEntryRepository;
+import de.thm.arsnova.persistence.MotdRepository;
+import de.thm.arsnova.persistence.RoomRepository;
+import de.thm.arsnova.persistence.SessionStatisticsRepository;
+import de.thm.arsnova.persistence.StatisticsRepository;
+import de.thm.arsnova.persistence.UserRepository;
+
 @Profile("test")
 @Configuration
 public class TestPersistanceConfig {
diff --git a/src/test/java/de/thm/arsnova/config/TestSecurityConfig.java b/src/test/java/de/thm/arsnova/config/TestSecurityConfig.java
index 7afd4e027..34750f976 100644
--- a/src/test/java/de/thm/arsnova/config/TestSecurityConfig.java
+++ b/src/test/java/de/thm/arsnova/config/TestSecurityConfig.java
@@ -15,9 +15,9 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.config;
 
-import de.thm.arsnova.security.CasUserDetailsService;
 import org.jasig.cas.client.validation.Cas20ProxyTicketValidator;
 import org.pac4j.oauth.client.FacebookClient;
 import org.pac4j.oauth.client.TwitterClient;
@@ -36,6 +36,8 @@ import org.springframework.security.config.annotation.web.configuration.EnableWe
 import org.springframework.security.core.session.SessionRegistry;
 import org.springframework.security.core.session.SessionRegistryImpl;
 
+import de.thm.arsnova.security.CasUserDetailsService;
+
 @Configuration
 @EnableGlobalMethodSecurity(mode = AdviceMode.ASPECTJ, prePostEnabled = true)
 @EnableWebSecurity
diff --git a/src/test/java/de/thm/arsnova/controller/AbstractControllerTest.java b/src/test/java/de/thm/arsnova/controller/AbstractControllerTest.java
index 9d4f39e59..ef63d662a 100644
--- a/src/test/java/de/thm/arsnova/controller/AbstractControllerTest.java
+++ b/src/test/java/de/thm/arsnova/controller/AbstractControllerTest.java
@@ -15,14 +15,11 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.controller;
 
-import de.thm.arsnova.config.AppConfig;
-import de.thm.arsnova.config.TestAppConfig;
-import de.thm.arsnova.config.TestPersistanceConfig;
-import de.thm.arsnova.config.TestSecurityConfig;
-import de.thm.arsnova.config.WebSocketConfig;
-import de.thm.arsnova.service.StubUserService;
+import java.util.ArrayList;
+import java.util.List;
 import org.junit.After;
 import org.junit.runner.RunWith;
 import org.springframework.beans.factory.annotation.Autowired;
@@ -35,8 +32,12 @@ import org.springframework.test.context.junit4.AbstractJUnit4SpringContextTests;
 import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
 import org.springframework.test.context.web.WebAppConfiguration;
 
-import java.util.ArrayList;
-import java.util.List;
+import de.thm.arsnova.config.AppConfig;
+import de.thm.arsnova.config.TestAppConfig;
+import de.thm.arsnova.config.TestPersistanceConfig;
+import de.thm.arsnova.config.TestSecurityConfig;
+import de.thm.arsnova.config.WebSocketConfig;
+import de.thm.arsnova.service.StubUserService;
 
 @RunWith(SpringJUnit4ClassRunner.class)
 @WebAppConfiguration
diff --git a/src/test/java/de/thm/arsnova/controller/v2/AuthenticationControllerTest.java b/src/test/java/de/thm/arsnova/controller/v2/AuthenticationControllerTest.java
index 5efa24841..9dbf5bc46 100644
--- a/src/test/java/de/thm/arsnova/controller/v2/AuthenticationControllerTest.java
+++ b/src/test/java/de/thm/arsnova/controller/v2/AuthenticationControllerTest.java
@@ -15,10 +15,16 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.controller.v2;
 
-import de.thm.arsnova.controller.AbstractControllerTest;
-import de.thm.arsnova.service.StubUserService;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotSame;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.content;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.jsonPath;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
 import org.junit.Before;
 import org.junit.Ignore;
 import org.junit.Test;
@@ -31,10 +37,8 @@ import org.springframework.test.web.servlet.MockMvc;
 import org.springframework.test.web.servlet.setup.MockMvcBuilders;
 import org.springframework.web.context.WebApplicationContext;
 
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertNotSame;
-import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
-import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.*;
+import de.thm.arsnova.controller.AbstractControllerTest;
+import de.thm.arsnova.service.StubUserService;
 
 public class AuthenticationControllerTest extends AbstractControllerTest {
 
diff --git a/src/test/java/de/thm/arsnova/controller/v2/CourseControllerTest.java b/src/test/java/de/thm/arsnova/controller/v2/CourseControllerTest.java
index 3068b1dcf..1f944e3de 100644
--- a/src/test/java/de/thm/arsnova/controller/v2/CourseControllerTest.java
+++ b/src/test/java/de/thm/arsnova/controller/v2/CourseControllerTest.java
@@ -15,11 +15,12 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.controller.v2;
 
-import de.thm.arsnova.connector.client.ConnectorClient;
-import de.thm.arsnova.controller.AbstractControllerTest;
-import de.thm.arsnova.service.StubUserService;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
 import org.junit.Before;
 import org.junit.Test;
 import org.mockito.InjectMocks;
@@ -30,8 +31,9 @@ import org.springframework.test.web.servlet.MockMvc;
 import org.springframework.test.web.servlet.setup.MockMvcBuilders;
 import org.springframework.web.context.WebApplicationContext;
 
-import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
-import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+import de.thm.arsnova.connector.client.ConnectorClient;
+import de.thm.arsnova.controller.AbstractControllerTest;
+import de.thm.arsnova.service.StubUserService;
 
 public class CourseControllerTest extends AbstractControllerTest {
 
diff --git a/src/test/java/de/thm/arsnova/event/StateEventDispatcherTest.java b/src/test/java/de/thm/arsnova/event/StateEventDispatcherTest.java
index 607220e06..6a0d592f3 100644
--- a/src/test/java/de/thm/arsnova/event/StateEventDispatcherTest.java
+++ b/src/test/java/de/thm/arsnova/event/StateEventDispatcherTest.java
@@ -15,20 +15,20 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.event;
 
+import static org.junit.Assert.assertEquals;
+import static org.mockito.AdditionalAnswers.returnsFirstArg;
+import static org.mockito.Matchers.any;
+import static org.mockito.Matchers.eq;
+import static org.mockito.Mockito.when;
+
 import com.fasterxml.jackson.databind.ObjectMapper;
-import de.thm.arsnova.config.AppConfig;
-import de.thm.arsnova.config.TestAppConfig;
-import de.thm.arsnova.config.TestPersistanceConfig;
-import de.thm.arsnova.config.TestSecurityConfig;
-import de.thm.arsnova.config.WebSocketConfig;
-import de.thm.arsnova.model.Content;
-import de.thm.arsnova.model.Room;
-import de.thm.arsnova.persistence.ContentRepository;
-import de.thm.arsnova.persistence.RoomRepository;
-import de.thm.arsnova.service.DefaultEntityServiceImpl;
-import de.thm.arsnova.test.context.support.WithMockUser;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
@@ -43,16 +43,17 @@ import org.springframework.test.context.ContextConfiguration;
 import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
 import org.springframework.test.context.web.WebAppConfiguration;
 
-import java.io.IOException;
-import java.util.ArrayList;
-import java.util.Collections;
-import java.util.List;
-
-import static org.junit.Assert.assertEquals;
-import static org.mockito.AdditionalAnswers.returnsFirstArg;
-import static org.mockito.Matchers.any;
-import static org.mockito.Matchers.eq;
-import static org.mockito.Mockito.when;
+import de.thm.arsnova.config.AppConfig;
+import de.thm.arsnova.config.TestAppConfig;
+import de.thm.arsnova.config.TestPersistanceConfig;
+import de.thm.arsnova.config.TestSecurityConfig;
+import de.thm.arsnova.config.WebSocketConfig;
+import de.thm.arsnova.model.Content;
+import de.thm.arsnova.model.Room;
+import de.thm.arsnova.persistence.ContentRepository;
+import de.thm.arsnova.persistence.RoomRepository;
+import de.thm.arsnova.service.DefaultEntityServiceImpl;
+import de.thm.arsnova.test.context.support.WithMockUser;
 
 @RunWith(SpringJUnit4ClassRunner.class)
 @WebAppConfiguration
diff --git a/src/test/java/de/thm/arsnova/model/ContentTest.java b/src/test/java/de/thm/arsnova/model/ContentTest.java
index b40506d1b..78ed369a3 100644
--- a/src/test/java/de/thm/arsnova/model/ContentTest.java
+++ b/src/test/java/de/thm/arsnova/model/ContentTest.java
@@ -15,16 +15,17 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model;
 
-import de.thm.arsnova.model.migration.v2.Answer;
-import de.thm.arsnova.model.migration.v2.AnswerOption;
-import de.thm.arsnova.model.migration.v2.Content;
-import org.junit.Test;
+import static org.junit.Assert.assertEquals;
 
 import java.util.ArrayList;
+import org.junit.Test;
 
-import static org.junit.Assert.assertEquals;
+import de.thm.arsnova.model.migration.v2.Answer;
+import de.thm.arsnova.model.migration.v2.AnswerOption;
+import de.thm.arsnova.model.migration.v2.Content;
 
 public class ContentTest {
 
diff --git a/src/test/java/de/thm/arsnova/model/EntityTest.java b/src/test/java/de/thm/arsnova/model/EntityTest.java
index 275eae31f..6e4c55069 100644
--- a/src/test/java/de/thm/arsnova/model/EntityTest.java
+++ b/src/test/java/de/thm/arsnova/model/EntityTest.java
@@ -15,16 +15,18 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-package de.thm.arsnova.model;
 
-import org.junit.Test;
-import org.springframework.core.style.ToStringCreator;
-
-import java.util.Date;
+package de.thm.arsnova.model;
 
 import static org.hamcrest.Matchers.endsWith;
 import static org.hamcrest.Matchers.startsWith;
-import static org.junit.Assert.*;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotEquals;
+import static org.junit.Assert.assertThat;
+
+import java.util.Date;
+import org.junit.Test;
+import org.springframework.core.style.ToStringCreator;
 
 /**
  * Tests {@link Entity}'s overrides for {@link Object#hashCode()}, {@link Object#equals(Object)}, and
diff --git a/src/test/java/de/thm/arsnova/model/FeedbackTest.java b/src/test/java/de/thm/arsnova/model/FeedbackTest.java
index b94bd0d70..5cc91beb6 100644
--- a/src/test/java/de/thm/arsnova/model/FeedbackTest.java
+++ b/src/test/java/de/thm/arsnova/model/FeedbackTest.java
@@ -15,13 +15,15 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model;
 
-import org.junit.Test;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
 
 import java.util.Optional;
-
-import static org.junit.Assert.*;
+import org.junit.Test;
 
 public class FeedbackTest {
 
diff --git a/src/test/java/de/thm/arsnova/model/TestClient.java b/src/test/java/de/thm/arsnova/model/TestClient.java
index 3cb03ea8e..d51426482 100644
--- a/src/test/java/de/thm/arsnova/model/TestClient.java
+++ b/src/test/java/de/thm/arsnova/model/TestClient.java
@@ -15,14 +15,15 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-package de.thm.arsnova.model;
 
-import de.thm.arsnova.model.migration.v2.ClientAuthentication;
-import org.springframework.security.core.GrantedAuthority;
+package de.thm.arsnova.model;
 
 import java.util.HashSet;
 import java.util.Set;
 import java.util.UUID;
+import org.springframework.security.core.GrantedAuthority;
+
+import de.thm.arsnova.model.migration.v2.ClientAuthentication;
 
 public class TestClient extends ClientAuthentication {
 	private static final long serialVersionUID = 1L;
diff --git a/src/test/java/de/thm/arsnova/model/migration/FromV2MigratorTest.java b/src/test/java/de/thm/arsnova/model/migration/FromV2MigratorTest.java
index 28c3f0bb9..475d4df81 100644
--- a/src/test/java/de/thm/arsnova/model/migration/FromV2MigratorTest.java
+++ b/src/test/java/de/thm/arsnova/model/migration/FromV2MigratorTest.java
@@ -15,8 +15,21 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model.migration;
 
+import static org.junit.Assert.assertEquals;
+
+import java.util.ArrayList;
+import java.util.List;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.test.context.ActiveProfiles;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+import org.springframework.test.context.web.WebAppConfiguration;
+
 import de.thm.arsnova.config.AppConfig;
 import de.thm.arsnova.config.TestAppConfig;
 import de.thm.arsnova.config.TestPersistanceConfig;
@@ -26,18 +39,6 @@ import de.thm.arsnova.model.ChoiceAnswer;
 import de.thm.arsnova.model.ChoiceQuestionContent;
 import de.thm.arsnova.model.Content;
 import de.thm.arsnova.model.migration.v2.Answer;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.test.context.ActiveProfiles;
-import org.springframework.test.context.ContextConfiguration;
-import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
-import org.springframework.test.context.web.WebAppConfiguration;
-
-import java.util.ArrayList;
-import java.util.List;
-
-import static org.junit.Assert.assertEquals;
 
 /**
  * @author Daniel Gerhardt
diff --git a/src/test/java/de/thm/arsnova/model/migration/ToV2MigratorTest.java b/src/test/java/de/thm/arsnova/model/migration/ToV2MigratorTest.java
index 7f798db33..9b96a2db2 100644
--- a/src/test/java/de/thm/arsnova/model/migration/ToV2MigratorTest.java
+++ b/src/test/java/de/thm/arsnova/model/migration/ToV2MigratorTest.java
@@ -15,8 +15,23 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.model.migration;
 
+import static org.junit.Assert.assertEquals;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.test.context.ActiveProfiles;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+import org.springframework.test.context.web.WebAppConfiguration;
+
 import de.thm.arsnova.config.AppConfig;
 import de.thm.arsnova.config.TestAppConfig;
 import de.thm.arsnova.config.TestPersistanceConfig;
@@ -27,20 +42,6 @@ import de.thm.arsnova.model.ChoiceAnswer;
 import de.thm.arsnova.model.ChoiceQuestionContent;
 import de.thm.arsnova.model.Content;
 import de.thm.arsnova.model.migration.v2.Answer;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.test.context.ActiveProfiles;
-import org.springframework.test.context.ContextConfiguration;
-import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
-import org.springframework.test.context.web.WebAppConfiguration;
-
-import java.util.ArrayList;
-import java.util.Arrays;
-import java.util.Collections;
-import java.util.List;
-
-import static org.junit.Assert.assertEquals;
 
 /**
  * @author Daniel Gerhardt
diff --git a/src/test/java/de/thm/arsnova/service/DefaultEntityServiceImplTest.java b/src/test/java/de/thm/arsnova/service/DefaultEntityServiceImplTest.java
index e07841c73..52a254ce9 100644
--- a/src/test/java/de/thm/arsnova/service/DefaultEntityServiceImplTest.java
+++ b/src/test/java/de/thm/arsnova/service/DefaultEntityServiceImplTest.java
@@ -15,17 +15,23 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.service;
 
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertSame;
+import static org.mockito.AdditionalAnswers.returnsFirstArg;
+import static org.mockito.Matchers.anyListOf;
+import static org.mockito.Mockito.any;
+import static org.mockito.Mockito.when;
+
 import com.fasterxml.jackson.databind.ObjectMapper;
-import de.thm.arsnova.config.AppConfig;
-import de.thm.arsnova.config.TestAppConfig;
-import de.thm.arsnova.config.TestPersistanceConfig;
-import de.thm.arsnova.config.TestSecurityConfig;
-import de.thm.arsnova.config.WebSocketConfig;
-import de.thm.arsnova.model.Room;
-import de.thm.arsnova.persistence.RoomRepository;
-import de.thm.arsnova.test.context.support.WithMockUser;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Optional;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.springframework.beans.factory.annotation.Autowired;
@@ -38,18 +44,14 @@ import org.springframework.test.context.ContextConfiguration;
 import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
 import org.springframework.test.context.web.WebAppConfiguration;
 
-import java.io.IOException;
-import java.util.ArrayList;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
-import java.util.Optional;
-
-import static org.junit.Assert.*;
-import static org.mockito.AdditionalAnswers.returnsFirstArg;
-import static org.mockito.Matchers.anyListOf;
-import static org.mockito.Mockito.any;
-import static org.mockito.Mockito.when;
+import de.thm.arsnova.config.AppConfig;
+import de.thm.arsnova.config.TestAppConfig;
+import de.thm.arsnova.config.TestPersistanceConfig;
+import de.thm.arsnova.config.TestSecurityConfig;
+import de.thm.arsnova.config.WebSocketConfig;
+import de.thm.arsnova.model.Room;
+import de.thm.arsnova.persistence.RoomRepository;
+import de.thm.arsnova.test.context.support.WithMockUser;
 
 
 @RunWith(SpringJUnit4ClassRunner.class)
diff --git a/src/test/java/de/thm/arsnova/service/FeedbackServiceTest.java b/src/test/java/de/thm/arsnova/service/FeedbackServiceTest.java
index 0fe0bd1d2..71cb00fed 100644
--- a/src/test/java/de/thm/arsnova/service/FeedbackServiceTest.java
+++ b/src/test/java/de/thm/arsnova/service/FeedbackServiceTest.java
@@ -1,10 +1,18 @@
 package de.thm.arsnova.service;
 
-import de.thm.arsnova.event.DeleteFeedbackForRoomsEvent;
-import de.thm.arsnova.model.Feedback;
-import de.thm.arsnova.model.Room;
-import de.thm.arsnova.web.exceptions.NoContentException;
-import de.thm.arsnova.web.exceptions.NotFoundException;
+import static org.junit.Assert.assertEquals;
+import static org.mockito.ArgumentMatchers.anyInt;
+import static org.mockito.ArgumentMatchers.anyString;
+import static org.mockito.ArgumentMatchers.argThat;
+import static org.mockito.ArgumentMatchers.eq;
+import static org.mockito.Mockito.lenient;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+import java.util.Arrays;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
@@ -13,15 +21,11 @@ import org.mockito.Mockito;
 import org.mockito.junit.MockitoJUnitRunner;
 import org.springframework.context.ApplicationEventPublisher;
 
-import java.util.Arrays;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
-
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.fail;
-import static org.mockito.ArgumentMatchers.*;
-import static org.mockito.Mockito.*;
+import de.thm.arsnova.event.DeleteFeedbackForRoomsEvent;
+import de.thm.arsnova.model.Feedback;
+import de.thm.arsnova.model.Room;
+import de.thm.arsnova.web.exceptions.NoContentException;
+import de.thm.arsnova.web.exceptions.NotFoundException;
 
 @RunWith(MockitoJUnitRunner.StrictStubs.class)
 public class FeedbackServiceTest {
diff --git a/src/test/java/de/thm/arsnova/service/StubUserService.java b/src/test/java/de/thm/arsnova/service/StubUserService.java
index e56dde169..3375e27c0 100644
--- a/src/test/java/de/thm/arsnova/service/StubUserService.java
+++ b/src/test/java/de/thm/arsnova/service/StubUserService.java
@@ -15,20 +15,21 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.service;
 
-import de.thm.arsnova.model.UserProfile;
-import de.thm.arsnova.persistence.UserRepository;
-import de.thm.arsnova.security.User;
+import java.util.HashSet;
+import java.util.Set;
+import java.util.UUID;
 import org.springframework.beans.factory.annotation.Qualifier;
 import org.springframework.http.converter.json.MappingJackson2HttpMessageConverter;
 import org.springframework.mail.javamail.JavaMailSender;
 import org.springframework.security.core.GrantedAuthority;
 import org.springframework.security.core.authority.SimpleGrantedAuthority;
 
-import java.util.HashSet;
-import java.util.Set;
-import java.util.UUID;
+import de.thm.arsnova.model.UserProfile;
+import de.thm.arsnova.persistence.UserRepository;
+import de.thm.arsnova.security.User;
 
 public class StubUserService extends UserServiceImpl {
 	private final Set<GrantedAuthority> grantedAuthorities;
diff --git a/src/test/java/de/thm/arsnova/service/UserServiceTest.java b/src/test/java/de/thm/arsnova/service/UserServiceTest.java
index 94daea8b4..710ce5582 100644
--- a/src/test/java/de/thm/arsnova/service/UserServiceTest.java
+++ b/src/test/java/de/thm/arsnova/service/UserServiceTest.java
@@ -15,28 +15,10 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.service;
 
-import de.thm.arsnova.config.AppConfig;
-import de.thm.arsnova.config.TestAppConfig;
-import de.thm.arsnova.config.TestPersistanceConfig;
-import de.thm.arsnova.config.TestSecurityConfig;
-import de.thm.arsnova.config.WebSocketConfig;
-import de.thm.arsnova.model.UserProfile;
-import de.thm.arsnova.model.migration.v2.ClientAuthentication;
-import de.thm.arsnova.security.User;
-import de.thm.arsnova.security.pac4j.OAuthToken;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.pac4j.core.profile.definition.CommonProfileDefinition;
-import org.pac4j.oidc.profile.google.GoogleOidcProfile;
-import org.springframework.security.authentication.AnonymousAuthenticationToken;
-import org.springframework.security.core.GrantedAuthority;
-import org.springframework.security.core.authority.SimpleGrantedAuthority;
-import org.springframework.test.context.ActiveProfiles;
-import org.springframework.test.context.ContextConfiguration;
-import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
-import org.springframework.test.context.web.WebAppConfiguration;
+import static org.junit.Assert.assertEquals;
 
 import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
@@ -49,8 +31,27 @@ import java.util.List;
 import java.util.Map;
 import java.util.UUID;
 import java.util.concurrent.ConcurrentHashMap;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.pac4j.core.profile.definition.CommonProfileDefinition;
+import org.pac4j.oidc.profile.google.GoogleOidcProfile;
+import org.springframework.security.authentication.AnonymousAuthenticationToken;
+import org.springframework.security.core.GrantedAuthority;
+import org.springframework.security.core.authority.SimpleGrantedAuthority;
+import org.springframework.test.context.ActiveProfiles;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+import org.springframework.test.context.web.WebAppConfiguration;
 
-import static org.junit.Assert.assertEquals;
+import de.thm.arsnova.config.AppConfig;
+import de.thm.arsnova.config.TestAppConfig;
+import de.thm.arsnova.config.TestPersistanceConfig;
+import de.thm.arsnova.config.TestSecurityConfig;
+import de.thm.arsnova.config.WebSocketConfig;
+import de.thm.arsnova.model.UserProfile;
+import de.thm.arsnova.model.migration.v2.ClientAuthentication;
+import de.thm.arsnova.security.User;
+import de.thm.arsnova.security.pac4j.OAuthToken;
 
 @RunWith(SpringJUnit4ClassRunner.class)
 @WebAppConfiguration
diff --git a/src/test/java/de/thm/arsnova/service/score/QuestionBasedScoreCalculatorTest.java b/src/test/java/de/thm/arsnova/service/score/QuestionBasedScoreCalculatorTest.java
index 0d6232e7a..216ec9274 100644
--- a/src/test/java/de/thm/arsnova/service/score/QuestionBasedScoreCalculatorTest.java
+++ b/src/test/java/de/thm/arsnova/service/score/QuestionBasedScoreCalculatorTest.java
@@ -15,19 +15,19 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-package de.thm.arsnova.service.score;
 
-import de.thm.arsnova.model.TestClient;
-import de.thm.arsnova.model.migration.v2.ClientAuthentication;
-import de.thm.arsnova.model.transport.ScoreStatistics;
-import de.thm.arsnova.persistence.SessionStatisticsRepository;
-import org.junit.Before;
-import org.junit.Test;
+package de.thm.arsnova.service.score;
 
 import static org.junit.Assert.assertEquals;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.when;
 
+import org.junit.Before;
+import org.junit.Test;
+
+import de.thm.arsnova.model.transport.ScoreStatistics;
+import de.thm.arsnova.persistence.SessionStatisticsRepository;
+
 public class QuestionBasedScoreCalculatorTest {
 
 	private Score courseScore;
diff --git a/src/test/java/de/thm/arsnova/service/score/ScoreBasedScoreCalculatorTest.java b/src/test/java/de/thm/arsnova/service/score/ScoreBasedScoreCalculatorTest.java
index be7afed80..9d694167f 100644
--- a/src/test/java/de/thm/arsnova/service/score/ScoreBasedScoreCalculatorTest.java
+++ b/src/test/java/de/thm/arsnova/service/score/ScoreBasedScoreCalculatorTest.java
@@ -15,17 +15,19 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-package de.thm.arsnova.service.score;
 
-import de.thm.arsnova.model.transport.ScoreStatistics;
-import de.thm.arsnova.persistence.SessionStatisticsRepository;
-import org.junit.Before;
-import org.junit.Test;
+package de.thm.arsnova.service.score;
 
 import static org.junit.Assert.assertEquals;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.when;
 
+import org.junit.Before;
+import org.junit.Test;
+
+import de.thm.arsnova.model.transport.ScoreStatistics;
+import de.thm.arsnova.persistence.SessionStatisticsRepository;
+
 public class ScoreBasedScoreCalculatorTest {
 
 	private Score courseScore;
diff --git a/src/test/java/de/thm/arsnova/test/context/support/WithMockUser.java b/src/test/java/de/thm/arsnova/test/context/support/WithMockUser.java
index db001d4e0..9e6a7512e 100644
--- a/src/test/java/de/thm/arsnova/test/context/support/WithMockUser.java
+++ b/src/test/java/de/thm/arsnova/test/context/support/WithMockUser.java
@@ -15,10 +15,8 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-package de.thm.arsnova.test.context.support;
 
-import de.thm.arsnova.model.UserProfile;
-import org.springframework.security.test.context.support.WithSecurityContext;
+package de.thm.arsnova.test.context.support;
 
 import java.lang.annotation.Documented;
 import java.lang.annotation.ElementType;
@@ -26,6 +24,9 @@ import java.lang.annotation.Inherited;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 import java.lang.annotation.Target;
+import org.springframework.security.test.context.support.WithSecurityContext;
+
+import de.thm.arsnova.model.UserProfile;
 
 /**
  * @author Daniel Gerhardt
diff --git a/src/test/java/de/thm/arsnova/test/context/support/WithMockUserSecurityContextFactory.java b/src/test/java/de/thm/arsnova/test/context/support/WithMockUserSecurityContextFactory.java
index 3da5ee7cc..6858e3fc7 100644
--- a/src/test/java/de/thm/arsnova/test/context/support/WithMockUserSecurityContextFactory.java
+++ b/src/test/java/de/thm/arsnova/test/context/support/WithMockUserSecurityContextFactory.java
@@ -15,10 +15,11 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.test.context.support;
 
-import de.thm.arsnova.model.UserProfile;
-import de.thm.arsnova.security.User;
+import java.util.Arrays;
+import java.util.stream.Collectors;
 import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
 import org.springframework.security.core.Authentication;
 import org.springframework.security.core.authority.SimpleGrantedAuthority;
@@ -27,8 +28,8 @@ import org.springframework.security.core.context.SecurityContextHolder;
 import org.springframework.security.test.context.support.WithSecurityContextFactory;
 import org.springframework.util.StringUtils;
 
-import java.util.Arrays;
-import java.util.stream.Collectors;
+import de.thm.arsnova.model.UserProfile;
+import de.thm.arsnova.security.User;
 
 /**
  * @author Daniel Gerhardt
diff --git a/src/test/java/de/thm/arsnova/util/ImageUtilsTest.java b/src/test/java/de/thm/arsnova/util/ImageUtilsTest.java
index 701ab910b..a1f47cf13 100644
--- a/src/test/java/de/thm/arsnova/util/ImageUtilsTest.java
+++ b/src/test/java/de/thm/arsnova/util/ImageUtilsTest.java
@@ -15,13 +15,16 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+
 package de.thm.arsnova.util;
 
-import de.thm.arsnova.config.AppConfig;
-import de.thm.arsnova.config.TestAppConfig;
-import de.thm.arsnova.config.TestPersistanceConfig;
-import de.thm.arsnova.config.TestSecurityConfig;
-import de.thm.arsnova.config.WebSocketConfig;
+import static de.thm.arsnova.util.ImageUtils.IMAGE_PREFIX_MIDDLE;
+import static de.thm.arsnova.util.ImageUtils.IMAGE_PREFIX_START;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertTrue;
+
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.springframework.test.context.ActiveProfiles;
@@ -29,9 +32,11 @@ import org.springframework.test.context.ContextConfiguration;
 import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
 import org.springframework.test.context.web.WebAppConfiguration;
 
-import static de.thm.arsnova.util.ImageUtils.IMAGE_PREFIX_MIDDLE;
-import static de.thm.arsnova.util.ImageUtils.IMAGE_PREFIX_START;
-import static org.junit.Assert.*;
+import de.thm.arsnova.config.AppConfig;
+import de.thm.arsnova.config.TestAppConfig;
+import de.thm.arsnova.config.TestPersistanceConfig;
+import de.thm.arsnova.config.TestSecurityConfig;
+import de.thm.arsnova.config.WebSocketConfig;
 
 @RunWith(SpringJUnit4ClassRunner.class)
 @WebAppConfiguration
diff --git a/src/test/java/de/thm/arsnova/websocket/handler/FeedbackCommandHandlerTest.java b/src/test/java/de/thm/arsnova/websocket/handler/FeedbackCommandHandlerTest.java
index 073c586e1..844234368 100644
--- a/src/test/java/de/thm/arsnova/websocket/handler/FeedbackCommandHandlerTest.java
+++ b/src/test/java/de/thm/arsnova/websocket/handler/FeedbackCommandHandlerTest.java
@@ -1,10 +1,9 @@
 package de.thm.arsnova.websocket.handler;
 
-import de.thm.arsnova.websocket.message.CreateFeedback;
-import de.thm.arsnova.websocket.message.CreateFeedbackPayload;
-import de.thm.arsnova.websocket.message.FeedbackChanged;
-import de.thm.arsnova.websocket.message.FeedbackChangedPayload;
-import de.thm.arsnova.websocket.message.GetFeedback;
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.Mockito.verify;
+
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
@@ -13,9 +12,11 @@ import org.springframework.boot.test.mock.mockito.MockBean;
 import org.springframework.messaging.simp.SimpMessagingTemplate;
 import org.springframework.test.context.junit4.SpringRunner;
 
-import static org.assertj.core.api.Assertions.assertThat;
-import static org.mockito.ArgumentMatchers.any;
-import static org.mockito.Mockito.verify;
+import de.thm.arsnova.websocket.message.CreateFeedback;
+import de.thm.arsnova.websocket.message.CreateFeedbackPayload;
+import de.thm.arsnova.websocket.message.FeedbackChanged;
+import de.thm.arsnova.websocket.message.FeedbackChangedPayload;
+import de.thm.arsnova.websocket.message.GetFeedback;
 
 @RunWith(SpringRunner.class)
 public class FeedbackCommandHandlerTest {
diff --git a/src/test/java/de/thm/arsnova/websocket/handler/FeedbackHandlerTest.java b/src/test/java/de/thm/arsnova/websocket/handler/FeedbackHandlerTest.java
index ebbdeb474..b95cd307a 100644
--- a/src/test/java/de/thm/arsnova/websocket/handler/FeedbackHandlerTest.java
+++ b/src/test/java/de/thm/arsnova/websocket/handler/FeedbackHandlerTest.java
@@ -1,6 +1,9 @@
 package de.thm.arsnova.websocket.handler;
 
-import de.thm.arsnova.websocket.message.CreateFeedback;
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.verify;
+
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
@@ -8,9 +11,7 @@ import org.mockito.ArgumentCaptor;
 import org.springframework.boot.test.mock.mockito.MockBean;
 import org.springframework.test.context.junit4.SpringRunner;
 
-import static org.assertj.core.api.Assertions.assertThat;
-import static org.mockito.Mockito.times;
-import static org.mockito.Mockito.verify;
+import de.thm.arsnova.websocket.message.CreateFeedback;
 
 @RunWith(SpringRunner.class)
 public class FeedbackHandlerTest {
-- 
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