diff --git a/src/main/java/envoy/data/Contact.java b/src/main/java/envoy/data/Contact.java
index e7a22ed..870aec8 100644
--- a/src/main/java/envoy/data/Contact.java
+++ b/src/main/java/envoy/data/Contact.java
@@ -23,7 +23,7 @@ public abstract class Contact implements Serializable {
 	/**
 	 * Creates a new instance of a {@link Contact}.
 	 *
-	 * @param id   the id of this contact
+	 * @param id   the ID of this contact
 	 * @param name the name of this contact
 	 * @since Envoy Common v0.1-beta
 	 */
@@ -45,12 +45,13 @@ public abstract class Contact implements Serializable {
 	public String getName() { return name; }
 
 	/**
-	 * @param newName the new name of this {@link Contact}
+	 * @param name the new name of this {@link Contact}
 	 * @since Envoy Common v0.1-beta
 	 */
-	public void setName(String newName) { name = newName; }
+	public void setName(String name) { this.name = name; }
 
 	/**
+	 * 
 	 * {@inheritDoc}
 	 */
 	@Override
diff --git a/src/main/java/envoy/data/Group.java b/src/main/java/envoy/data/Group.java
index 44f91d4..abc51d0 100644
--- a/src/main/java/envoy/data/Group.java
+++ b/src/main/java/envoy/data/Group.java
@@ -14,15 +14,15 @@ import java.util.StringJoiner;
  */
 public class Group extends Contact {
 
-	private static final long serialVersionUID = 0L;
-
 	// TODO add admins
 	private List<Long> memberIDs;
 
+	private static final long serialVersionUID = 0L;
+
 	/**
 	 * Creates a new instance of a {@link Group}.
 	 *
-	 * @param id   the id of this group
+	 * @param id   the ID of this group
 	 * @param name the name of this group
 	 * @since Envoy Common v0.1-beta
 	 */
@@ -31,7 +31,7 @@ public class Group extends Contact {
 	/**
 	 * Creates a new instance of a {@link Group}.
 	 *
-	 * @param id        the id of this group
+	 * @param id        the ID of this group
 	 * @param name      the name of this group
 	 * @param memberIDs the IDs of all members that should be preinitialized
 	 * @since Envoy Common v0.1-beta
@@ -61,7 +61,7 @@ public class Group extends Contact {
 		var joiner = new StringJoiner(",", "Group[id=", "]");
 		joiner.add("id=" + getID());
 		joiner.add("name=" + getName());
-		joiner.add("memberIDs=" + getMemberIDs());
+		joiner.add("members=" + getMemberIDs().size());
 		return joiner.toString();
 	}
 }
diff --git a/src/main/java/envoy/event/GroupCreationEvent.java b/src/main/java/envoy/event/GroupCreationEvent.java
index a2d393c..17810e9 100644
--- a/src/main/java/envoy/event/GroupCreationEvent.java
+++ b/src/main/java/envoy/event/GroupCreationEvent.java
@@ -19,5 +19,4 @@ public class GroupCreationEvent extends Event<String> {
 	 * @since Envoy Common v0.1-beta
 	 */
 	public GroupCreationEvent(String value) { super(value); }
-
 }
diff --git a/src/main/java/envoy/event/GroupResizeEvent.java b/src/main/java/envoy/event/GroupResizeEvent.java
index 8ad2ce5..af09c35 100644
--- a/src/main/java/envoy/event/GroupResizeEvent.java
+++ b/src/main/java/envoy/event/GroupResizeEvent.java
@@ -20,14 +20,14 @@ import envoy.data.User;
 public class GroupResizeEvent extends Event<Long> {
 
 	private final long		groupID;
-	private OperationType	operationType;
+	private Operation	operation;
 
 	private static final long serialVersionUID = 0L;
 
 	/**
 	 * This enum defines all possibilities for handling
 	 * {@link GroupResizeEvent}s.<br>
-	 * These can be: {@link OperationType#ADD} or {@link OperationType#REMOVE}.<br>
+	 * These can be: {@link Operation#ADD} or {@link Operation#REMOVE}.<br>
 	 * <br>
 	 * Project: <strong>envoy-common</strong><br>
 	 * File: <strong>GroupResizeEvent.java</strong><br>
@@ -36,7 +36,7 @@ public class GroupResizeEvent extends Event<Long> {
 	 * @author Leon Hofmeister
 	 * @since Envoy Common v0.1-beta
 	 */
-	public enum OperationType {
+	public enum Operation {
 		/**
 		 * Select this element, if the given {@link User} should be added to the given
 		 * {@link Group}
@@ -53,45 +53,44 @@ public class GroupResizeEvent extends Event<Long> {
 	 * Initializes a {@link GroupResizeEvent} through a Contact where the name has
 	 * already been set.
 	 *
-	 * @param user          the {@link User} who wants to join or leave a group
-	 * @param group         the {@link Group} he wants to join or leave
-	 * @param operationType whether the user should be removed from this group. If
-	 *                      false,
-	 *                      this user will be added
+	 * @param user      the {@link User} who wants to join or leave a group
+	 * @param group     the {@link Group} he wants to join or leave
+	 * @param operation whether the user should be removed from this group. If
+	 *                  false, this user will be added.
 	 * @since Envoy Common v0.2-alpha
 	 */
-	public GroupResizeEvent(User user, Group group, OperationType operationType) {
+	public GroupResizeEvent(User user, Group group, Operation operation) {
 		super(user.getID());
 		if (group.getMemberIDs().contains(user.getID())) {
-			if (operationType.equals(OperationType.ADD)) throw new IllegalStateException(
+			if (operation.equals(Operation.ADD)) throw new IllegalStateException(
 					"Cannot add " + user + " to group " + group.getID() + " because he is already a member of this group");
-		} else if (operationType.equals(OperationType.REMOVE))
+		} else if (operation.equals(Operation.REMOVE))
 			throw new IllegalStateException("Cannot remove " + user + " from group " + group.getID() + " because he is no part of this group");
 		groupID				= group.getID();
-		this.operationType	= operationType;
+		this.operation	= operation;
 	}
 
 	/**
 	 * @return the ID of the {@link Contact} this event is related to
 	 * @since Envoy Common v0.2-alpha
 	 */
-	public long getGroupId() { return groupID; }
+	public long getGroupID() { return groupID; }
 
 	/**
 	 * @return the operationType
 	 * @since Envoy Common v0.1-beta
 	 */
-	public OperationType getOperationType() { return operationType; }
+	public Operation getOperationType() { return operation; }
 
 	/**
-	 * @param operationType the operationType to set
+	 * @param operation the operationType to set
 	 * @since Envoy Common v0.1-beta
 	 */
-	public void setOperationType(OperationType operationType) { this.operationType = operationType; }
+	public void setOperationType(Operation operation) { this.operation = operation; }
 
 	/**
 	 * {@inheritDoc}
 	 */
 	@Override
-	public String toString() { return String.format("GroupResizeEvent[userid=%d,groupid=%d,operationType=%b]", get(), groupID, operationType); }
+	public String toString() { return String.format("GroupResizeEvent[userid=%d,groupid=%d,operation=%b]", get(), groupID, operation); }
 }
diff --git a/src/main/java/envoy/event/NameChangeEvent.java b/src/main/java/envoy/event/NameChangeEvent.java
index 4cfa640..76f6e46 100644
--- a/src/main/java/envoy/event/NameChangeEvent.java
+++ b/src/main/java/envoy/event/NameChangeEvent.java
@@ -16,8 +16,9 @@ import envoy.data.Contact;
  */
 public class NameChangeEvent extends Event<String> {
 
+	private final long id;
+
 	private static final long	serialVersionUID	= 0L;
-	private final long			id;
 
 	/**
 	 * Creates a new {@link NameChangeEvent} for a user or a group.
@@ -48,5 +49,4 @@ public class NameChangeEvent extends Event<String> {
 
 	@Override
 	public String toString() { return String.format("NameChangeEvent[id=%d,name=%s]", id, value); }
-
 }