* check before add a user to the map beacause if its maybe unauthorized

* rename methods to clearify that this are sockets

src/main/java/de/thm/arsnova/controller/SessionController.java

@@ -66,7 +66,9 @@ public class SessionController extends AbstractController {
 		User u = userService.getCurrentUser();
 		LOGGER.info("authorize session: " + socketid + ", user is:  " + u);
 		response.setStatus(u != null ? HttpStatus.CREATED.value() : HttpStatus.UNAUTHORIZED.value());
-		userService.putUser2SessionID(UUID.fromString(socketid), u);
+		if(u != null) {
+			userService.putUser2SocketId(UUID.fromString(socketid), u);	
+		}		
 	}
 
 	@RequestMapping(value = "/session/{sessionkey}", method = RequestMethod.GET)

src/main/java/de/thm/arsnova/services/IUserService.java

@@ -29,13 +29,13 @@ import de.thm.arsnova.entities.User;
 public interface IUserService {
 	User getCurrentUser();
 
-	User getUser2SessionID(UUID sessionID);
+	User getUser2SocketId(UUID socketId);
 
-	void putUser2SessionID(UUID sessionID, User user);
+	void putUser2SocketId(UUID socketId, User user);
 
-	void removeUser2SessionID(UUID sessionID);
+	void removeUser2SocketId(UUID socketId);
 
-	Set<Map.Entry<UUID, User>> users2Session();
+	Set<Map.Entry<UUID, User>> socketId2User();
 
 	boolean isUserInSession(User user, String keyword);
 

src/main/java/de/thm/arsnova/services/UserService.java

@@ -83,23 +83,23 @@ public class UserService implements IUserService, InitializingBean, DisposableBe
 	}
 
 	@Override
-	public User getUser2SessionID(UUID sessionID) {
-		return socketid2user.get(sessionID);
+	public User getUser2SocketId(UUID socketId) {
+		return socketid2user.get(socketId);
 	}
 
 	@Override
-	public void putUser2SessionID(UUID sessionID, User user) {
-		socketid2user.put(sessionID, user);
+	public void putUser2SocketId(UUID socketId, User user) {
+		socketid2user.put(socketId, user);
 	}
 
 	@Override
-	public Set<Map.Entry<UUID, User>> users2Session() {
+	public Set<Map.Entry<UUID, User>> socketId2User() {
 		return socketid2user.entrySet();
 	}
 
 	@Override
-	public void removeUser2SessionID(UUID sessionID) {
-		socketid2user.remove(sessionID);
+	public void removeUser2SocketId(UUID socketId) {
+		socketid2user.remove(socketId);
 	}
 
 	@Override

src/main/java/de/thm/arsnova/socket/ARSnovaSocketIOServer.java

@@ -82,7 +82,7 @@ public class ARSnovaSocketIOServer {
 						 * do a check if user is in the session, for which he
 						 * would give a feedback
 						 */
-						User u = userService.getUser2SessionID(client
+						User u = userService.getUser2SocketId(client
 								.getSessionId());
 						if (u == null
 								|| userService.isUserInSession(u,
@@ -103,7 +103,7 @@ public class ARSnovaSocketIOServer {
 								.getFeedback(data.getSessionkey());
 
 						for (SocketIOClient c : server.getAllClients()) {
-							u = userService.getUser2SessionID(c.getSessionId());
+							u = userService.getUser2SocketId(c.getSessionId());
 							if (u != null && users.contains(u.getUsername())) {
 								c.sendEvent("updateFeedback", fb.getValues());
 							}
@@ -133,7 +133,7 @@ public class ARSnovaSocketIOServer {
 			public void onDisconnect(SocketIOClient client) {
 				logger.info("addDisconnectListener.onDisconnect: Client: {}",
 						new Object[] { client });
-				userService.removeUser2SessionID(client.getSessionId());
+				userService.removeUser2SocketId(client.getSessionId());
 			}
 		});
 
@@ -210,7 +210,7 @@ public class ARSnovaSocketIOServer {
 
 	private List<UUID> findConnectionIdForUser(String username) {
 		List<UUID> result = new ArrayList<UUID>();
-		for (Entry<UUID, User> e : userService.users2Session()) {
+		for (Entry<UUID, User> e : userService.socketId2User()) {
 			if (e.getValue().getUsername().equals(username)) {
 				result.add(e.getKey());
 			}