Contacts events

Created 2 events used for the contact list (add/remove) of the client
and requesting a list of users form the server.

src/main/java/envoy/event/ContactOperation.java

@@ -0,0 +1,50 @@
+package envoy.event;
+
+import envoy.data.User;
+
+/**
+ * Project: <strong>envoy-common</strong><br>
+ * File: <strong>ContactOperation.java</strong><br>
+ * Created: <strong>05.02.2020</strong><br>
+ * 
+ * @author Maximilian K&auml;fer
+ * @since Envoy Common v0.2-alpha
+ */
+public class ContactOperation implements Event<User> {
+
+	public enum Operation {
+		ADD, REMOVE;
+	}
+
+	private final User		contact;
+	private final Operation	operationType;
+
+	private static final long serialVersionUID = -1166652868189511553L;
+
+	/**
+	 * Initializes a {@link ContacsOperation}.
+	 * 
+	 * @param operationType the {@link Operation} which should be executed on the
+	 *                      {@link contact}.
+	 * @since Envoy Common v0.2-alpha
+	 */
+	public ContactOperation(User contact, Operation operationType) {
+		this.contact		= contact;
+		this.operationType	= operationType;
+	}
+
+	/**
+	 * @return the {@link User}, which should be added/removed from the contacts
+	 *         list.
+	 * @since Envoy Common v0.2-alpha
+	 */
+	@Override
+	public User get() { return contact; }
+
+	/**
+	 * @return the {@link Operation}, which should be executed with the contact,
+	 *         this event corresponds with.
+	 * @since Envoy Common v0.2-alpha
+	 */
+	public Operation getOperationType() { return operationType; }
+}

src/main/java/envoy/event/ContactsRequest.java

@@ -0,0 +1,32 @@
+package envoy.event;
+
+/**
+ * Project: <strong>envoy-common</strong><br>
+ * File: <strong>ContactsRequest.java</strong><br>
+ * Created: <strong>05.02.2020</strong><br>
+ * 
+ * @author Maximilian K&auml;fer
+ * @since Envoy Common v0.2-alpha
+ */
+public class ContactsRequest implements Event<String> {
+
+	private final String request;
+
+	private static final long serialVersionUID = -7969312055630533627L;
+
+	/**
+	 * Initializes a {@link ContactsRequest}.
+	 * 
+	 * @param request the string, which is entered by the client to request
+	 *                corresponding clients as contacts from the server.
+	 * @since Envoy Common v0.2-alpha
+	 */
+	public ContactsRequest(String request) { this.request = request; }
+
+	/**
+	 * @return the request string
+	 * @since Envoy Common v0.2-alpha
+	 */
+	@Override
+	public String get() { return request; }
+}