Merge branch 'refactoring' into error-handling

# Conflicts:
#	src/main/java/mops/gruppen2/controller/Gruppen2Controller.java
#	src/main/java/mops/gruppen2/domain/Exceptions/UserAlreadyExistsException.java
#	src/main/java/mops/gruppen2/domain/Exceptions/UserNotFoundException.java
#	src/main/java/mops/gruppen2/domain/Group.java
#	src/main/java/mops/gruppen2/domain/event/AddUserEvent.java
#	src/main/java/mops/gruppen2/domain/event/CreateGroupEvent.java
#	src/main/java/mops/gruppen2/domain/event/DeleteUserEvent.java
#	src/main/java/mops/gruppen2/domain/event/Event.java
#	src/main/java/mops/gruppen2/domain/event/UpdateGroupDescriptionEvent.java
#	src/main/java/mops/gruppen2/domain/event/UpdateGroupTitleEvent.java
#	src/main/java/mops/gruppen2/domain/event/UpdateRoleEvent.java
#	src/main/java/mops/gruppen2/domain/exception/EventException.java
#	src/main/java/mops/gruppen2/domain/exception/GroupIdMismatchException.java
#	src/main/java/mops/gruppen2/domain/exception/GroupNotFoundException.java
#	src/main/java/mops/gruppen2/domain/exception/NoValueException.java
#	src/main/java/mops/gruppen2/service/ControllerService.java
#	src/main/java/mops/gruppen2/service/GroupService.java
#	src/main/java/mops/gruppen2/service/UserService.java
#	src/main/resources/templates/errorRenameLater.html

src/main/java/mops/gruppen2/domain/exception/EventException.java

@@ -0,0 +1,12 @@
+package mops.gruppen2.domain.exception;
+
+import org.springframework.http.HttpStatus;
+import org.springframework.web.server.ResponseStatusException;
+
+public abstract class EventException extends ResponseStatusException {
+
+    public EventException(HttpStatus status, String msg, String info) {
+        super(status, msg + "    (" + info + ")");
+    }
+
+}

src/main/java/mops/gruppen2/domain/exception/GroupIdMismatchException.java

@@ -0,0 +1,10 @@
+package mops.gruppen2.domain.Exceptions;
+
+import org.springframework.http.HttpStatus;
+
+public class GroupIdMismatchException extends EventException {
+
+    public GroupIdMismatchException(String info) {
+        super(HttpStatus.INTERNAL_SERVER_ERROR, "Falsche Gruppe für Event.", info);
+    }
+}

src/main/java/mops/gruppen2/domain/exception/GroupNotFoundException.java

@@ -0,0 +1,10 @@
+package mops.gruppen2.domain.Exceptions;
+
+import org.springframework.http.HttpStatus;
+
+public class GroupNotFoundException extends EventException {
+
+    public GroupNotFoundException(String info) {
+        super(HttpStatus.NOT_FOUND, "Gruppe wurde nicht gefunden.", info);
+    }
+}

src/main/java/mops/gruppen2/domain/exception/NoValueException.java

@@ -0,0 +1,10 @@
+package mops.gruppen2.domain.Exceptions;
+
+import org.springframework.http.HttpStatus;
+
+public class NoValueException extends EventException {
+
+    public NoValueException(String info) {
+        super(HttpStatus.NO_CONTENT, "Eine Information fehlt.", info);
+    }
+}

src/main/java/mops/gruppen2/domain/exception/UserAlreadyExistsException.java

@@ -0,0 +1,8 @@
+package mops.gruppen2.domain.exception;
+
+public class UserAlreadyExistsException extends EventException {
+
+    public UserAlreadyExistsException(String msg) {
+        super(msg);
+    }
+}

src/main/java/mops/gruppen2/domain/exception/UserNotFoundException.java

@@ -0,0 +1,8 @@
+package mops.gruppen2.domain.exception;
+
+public class UserNotFoundException extends EventException {
+
+    public UserNotFoundException(String msg) {
+        super(msg);
+    }
+}