try to make naming more consistent

src/main/java/mops/gruppen2/domain/Group.java

@@ -18,50 +18,50 @@ import java.util.Map;
 @Data
 public class Group extends Aggregate {
 	long id;
-	String titel;
-	String beschreibung;
-	List<User> teilnehmersList;
-	Map<User, Role> rollenList;
+	String title;
+	String description;
+	List<User> members;
+	Map<User, Role> roles;
 
 	public void applyEvent(CreateGroupEvent event){
-		this.id = event.getGruppe_id();
-		this.titel = event.getTitel();
-		this.beschreibung = event.getBeschreibung();
-		this.teilnehmersList = new ArrayList<>();
-		this.rollenList = new HashMap<>();
+		this.id = event.getGroup_id();
+		this.title = event.getGroupTitle();
+		this.description = event.getGroupDescription();
+		this.members = new ArrayList<>();
+		this.roles = new HashMap<>();
 	}
 
 	public void applyEvent(UpdateRoleEvent event) {
-		teilnehmersList.stream()
-				.filter(user -> user.getId().equals(event.getUser_id()))
+		members.stream()
+				.filter(user -> user.getUser_id().equals(event.getUser_id()))
 				.findFirst()
-				.ifPresentOrElse(user -> rollenList.put(user, event.getRole()),
+				.ifPresentOrElse(user -> roles.put(user, event.getNewRole()),
 						() -> System.out.println("UserNotFoundException"));
 	}
 
 	public void  applyEvent(AddUserEvent event){
 		User user = new User();
 
-		user.setId(event.getUser_id());
-		user.setVorname(event.getVorname());
-		user.setNachname(event.getNachname());
+		user.setUser_id(event.getUser_id());
+		user.setGivenname(event.getGivenname());
+		user.setFamilyname(event.getFamilyname());
 		user.setEmail(event.getEmail());
 
-		this.teilnehmersList.add(user);
+		this.members.add(user);
 	}
 
 	public void applyEvent(UpdateGroupTitleEvent event) {
-		this.titel = event.getTitel();
+		this.title = event.getNewGroupTitle();
 	}
 
 	public void applyEvent(UpdateGroupDescriptionEvent event) {
-		this.beschreibung = event.getBeschreibung();
+		this.description = event.getNewGroupDescription();
 	}
 
 	public void applyEvent(DeleteUserEvent event) {
-		for (User user : teilnehmersList) {
-			if (user.getId().equals(event.getUser_id())) {
-				this.teilnehmersList.remove(user);
+		for (User user : members) {
+			if (user.getUser_id().equals(event.getUser_id())) {
+				this.members.remove(user);
 				break;
 			}
 		}

src/main/java/mops/gruppen2/domain/User.java

@@ -1,14 +1,13 @@
 package mops.gruppen2.domain;
 
+import lombok.AllArgsConstructor;
 import lombok.Data;
 
-import java.util.List;
-
 @Data
+@AllArgsConstructor
 public class User {
-	String id;
-	String vorname;
-	String nachname;
+	String user_id;
+	String givenname;
+	String familyname;
 	String email;
-	List<Group> gruppen;
 }

src/main/java/mops/gruppen2/domain/event/AddUserEvent.java

@@ -4,12 +4,12 @@ import lombok.Getter;
 
 @Getter
 public class AddUserEvent extends Event{
-	String vorname, nachname, email;
+	String givenname, familyname, email;
 
-	public AddUserEvent(long id, long gruppe_id, String user_id, String vorname, String nachname, String email) {
-		super(id, gruppe_id, user_id);
-		this.vorname = vorname;
-		this.nachname = nachname;
+	public AddUserEvent(long event_id, long group_id, String user_id, String givenname, String familyname, String email) {
+		super(event_id, group_id, user_id);
+		this.givenname = givenname;
+		this.familyname = familyname;
 		this.email = email;
 	}
 }

src/main/java/mops/gruppen2/domain/event/CreateGroupEvent.java

@@ -4,12 +4,12 @@ import lombok.Getter;
 
 @Getter
 public class CreateGroupEvent extends Event {
-	String titel;
-	String beschreibung;
+	String groupTitle;
+	String groupDescription;
 
-	public CreateGroupEvent(long id, long gruppe_id, String user_id, String titel, String beschreibung) {
-		super(id, gruppe_id, user_id);
-		this.titel = titel;
-		this.beschreibung = beschreibung;
+	public CreateGroupEvent(long event_id, long group_id, String user_id, String groupTitle, String groupDescription) {
+		super(event_id, group_id, user_id);
+		this.groupTitle = groupTitle;
+		this.groupDescription = groupDescription;
 	}
 }

src/main/java/mops/gruppen2/domain/event/DeleteUserEvent.java

@@ -5,7 +5,7 @@ import lombok.Getter;
 @Getter
 public class DeleteUserEvent extends Event{
 
-    public DeleteUserEvent(long id, long gruppe_id, String user_id) {
-        super(id, gruppe_id, user_id);
+    public DeleteUserEvent(long event_id, long group_id, String user_id) {
+        super(event_id, group_id, user_id);
     }
 }

src/main/java/mops/gruppen2/domain/event/Event.java

@@ -6,7 +6,7 @@ import lombok.Getter;
 @Getter
 @AllArgsConstructor
 public class Event {
-	long id;
-	long gruppe_id;
+	long event_id;
+	long group_id;
 	String user_id;
 }

src/main/java/mops/gruppen2/domain/event/UpdateGroupDescriptionEvent.java

@@ -4,10 +4,10 @@ import lombok.Getter;
 
 @Getter
 public class UpdateGroupDescriptionEvent extends Event {
-    String beschreibung;
+    String newGroupDescription;
 
-    public UpdateGroupDescriptionEvent(long id, long gruppe_id, String user_id, String beschreibung) {
-        super(id, gruppe_id, user_id);
-        this.beschreibung = beschreibung;
+    public UpdateGroupDescriptionEvent(long event_id, long group_id, String user_id, String newGroupDescription) {
+        super(event_id, group_id, user_id);
+        this.newGroupDescription = newGroupDescription;
     }
 }

src/main/java/mops/gruppen2/domain/event/UpdateGroupTitleEvent.java

@@ -4,10 +4,10 @@ import lombok.Getter;
 
 @Getter
 public class UpdateGroupTitleEvent extends Event {
-    String titel;
+    String newGroupTitle;
 
-    public UpdateGroupTitleEvent(long id, long gruppe_id, String user_id, String titel) {
-        super(id, gruppe_id, user_id);
-        this.titel = titel;
+    public UpdateGroupTitleEvent(long event_id, long group_id, String user_id, String newGroupTitle) {
+        super(event_id, group_id, user_id);
+        this.newGroupTitle = newGroupTitle;
     }
 }

src/main/java/mops/gruppen2/domain/event/UpdateRoleEvent.java

@@ -6,11 +6,11 @@ import mops.gruppen2.domain.Role;
 @Getter
 public class UpdateRoleEvent extends Event {
 
-    private final Role role;
+    private final Role newRole;
 
-    public UpdateRoleEvent(long id, long gruppe_id, String user_id, Role newRole) {
-        super(id, gruppe_id, user_id);
+    public UpdateRoleEvent(long event_id, long group_id, String user_id, Role newRole) {
+        super(event_id, group_id, user_id);
 
-        this.role = newRole;
+        this.newRole = newRole;
     }
 }

src/main/java/mops/gruppen2/service/GroupService.java

@@ -8,9 +8,11 @@ import java.util.List;
 @Service
 public class GroupService {
 
-	Group buildGroup(List<Event> eventList){
+	Group buildGroupFromEvents(List<Event> eventList){
 		Group newGroup = new Group();
+
 		eventList.forEach(newGroup::applyEvent);
+
 		return newGroup;
 	}
 }