diff --git a/src/main/java/de/thm/arsnova/dao/IDatabaseDao.java b/src/main/java/de/thm/arsnova/dao/IDatabaseDao.java
index 17fba6ffee234655d4c8c686daa36728e8fdf3a9..092e267e2ab698852b4b21f3afcb77b17057ba00 100644
--- a/src/main/java/de/thm/arsnova/dao/IDatabaseDao.java
+++ b/src/main/java/de/thm/arsnova/dao/IDatabaseDao.java
@@ -18,10 +18,7 @@
 package de.thm.arsnova.dao;
 
 import java.util.AbstractMap.SimpleEntry;
-import java.util.ArrayList;
 import java.util.List;
-import java.util.Map;
-
 import de.thm.arsnova.connector.model.Course;
 import de.thm.arsnova.entities.Answer;
 import de.thm.arsnova.entities.DbUser;
@@ -39,9 +36,9 @@ public interface IDatabaseDao {
 	Session getSession(String keyword);
 
 	List<Session> getMySessions(User user);
-	
+
 	List<Session> getPublicPoolSessions();
-	
+
 	List<Session> getMyPublicPoolSessions(User user);
 
 	Session saveSession(User user, Session session);
@@ -75,7 +72,7 @@ public interface IDatabaseDao {
 	List<Answer> getAnswers(String questionId, int piRound);
 
 	int getAnswerCount(Question question, int piRound);
-	
+
 	int getAbstentionAnswerCount(String questionId);
 
 	List<Answer> getFreetextAnswers(String questionId);
@@ -159,7 +156,7 @@ public interface IDatabaseDao {
 	void deleteAllInterposedQuestions(Session session);
 
 	void deleteAllInterposedQuestions(Session session, User user);
-	
+
 	void publishQuestions(Session session, boolean publish, List<Question> questions);
 
 	void publishAllQuestions(Session session, boolean publish);
@@ -177,11 +174,11 @@ public interface IDatabaseDao {
 	SimpleEntry<Integer, Integer> getMyLearningProgress(Session session, User user);
 
 	List<SessionInfo> getMySessionsInfo(User user);
-	
+
 	List<SessionInfo> getPublicPoolSessionsInfo();
 
 	List<SessionInfo> getMyPublicPoolSessionsInfo(final User user);
-	
+
 	List<SessionInfo> getMyVisitedSessionsInfo(User currentUser);
 
 	void deleteAllPreparationAnswers(Session session);
diff --git a/src/main/java/de/thm/arsnova/services/SessionService.java b/src/main/java/de/thm/arsnova/services/SessionService.java
index 330f0bde143df7c836b1f605c0e7a05aeb35ff89..8da5105bc013ebb32ed1cfe0553186bcde008d03 100644
--- a/src/main/java/de/thm/arsnova/services/SessionService.java
+++ b/src/main/java/de/thm/arsnova/services/SessionService.java
@@ -19,10 +19,8 @@ package de.thm.arsnova.services;
 
 import java.io.Serializable;
 import java.util.AbstractMap.SimpleEntry;
-import java.util.ArrayList;
 import java.util.Comparator;
 import java.util.List;
-import java.util.Map;
 import java.util.UUID;
 
 import org.springframework.beans.factory.annotation.Autowired;
diff --git a/src/test/java/de/thm/arsnova/dao/StubDatabaseDao.java b/src/test/java/de/thm/arsnova/dao/StubDatabaseDao.java
index b3c85df2f112f97f4708e5d0cc89dc0ae1cdd696..ab187a6342197304ba5321a403c5e2660f7d3101 100644
--- a/src/test/java/de/thm/arsnova/dao/StubDatabaseDao.java
+++ b/src/test/java/de/thm/arsnova/dao/StubDatabaseDao.java
@@ -193,25 +193,25 @@ public class StubDatabaseDao implements IDatabaseDao {
 		// TODO Auto-generated method stub
 		return null;
 	}
-	
+
 	@Override
 	public List<Session> getPublicPoolSessions() {
 		// TODO Auto-generated method stub
 		return null;
 	}
-	
+
 	@Override
 	public List<SessionInfo> getPublicPoolSessionsInfo() {
 		// TODO Auto-generated method stub
 		return null;
 	}
-	
+
 	@Override
 	public List<Session> getMyPublicPoolSessions(User user) {
 		// TODO Auto-generated method stub
 		return null;
 	}
-	
+
 	@Override
 	public List<SessionInfo> getMyPublicPoolSessionsInfo(final User user) {
 		// TODO Auto-generated method stub
@@ -477,7 +477,7 @@ public class StubDatabaseDao implements IDatabaseDao {
 	public void deleteAllInterposedQuestions(Session session) {
 		// TODO Auto-generated method stub
 	}
-	
+
 	@Override
 	public void publishQuestions(Session session, boolean publish, List<Question> questions) {
 		// TODO Auto-generated method stub