Added HandshakeRejectionEvent and fixed some Javadoc

src/main/java/envoy/event/HandshakeRejectionEvent.java

@@ -0,0 +1,41 @@
+package envoy.event;
+
+/**
+ * Signifies to the client that the handshake failed for the attached
+ * reason.<br>
+ * <br>
+ * Project: <strong>envoy-common</strong><br>
+ * File: <strong>HandshakeRejectionEvent.java</strong><br>
+ * Created: <strong>28 Jan 2020</strong><br>
+ *
+ * @author Kai S. K. Engelbart
+ * @since Envoy Common v0.3-alpha
+ */
+public class HandshakeRejectionEvent implements Event<String> {
+
+	private final String reason;
+
+	private static final long serialVersionUID = -8723270093452609197L;
+
+	/**
+	 * Creates an instance of {@link HandshakeRejectionEvent} with an empty reason.
+	 *
+	 * @since Envoy Common v0.3-alpha
+	 */
+	public HandshakeRejectionEvent() { this(""); }
+
+	/**
+	 * Creates an instance of {@link HandshakeRejectionEvent}.
+	 *
+	 * @param reason the reason why the handshake was rejected
+	 * @since Envoy Common v0.3-alpha
+	 */
+	public HandshakeRejectionEvent(String reason) { this.reason = reason; }
+
+	/**
+	 * @return the reason why the handshake was rejected
+	 * @since Envoy Common v0.3-alpha
+	 */
+	@Override
+	public String get() { return reason; }
+}

src/main/java/envoy/event/IdGeneratorRequest.java

@@ -9,6 +9,7 @@ package envoy.event;
  * Created: <strong>28 Jan 2020</strong><br>
  *
  * @author Kai S. K. Engelbart
+ * @since Envoy Common v0.3-alpha
  */
 public class IdGeneratorRequest implements Event<Void> {
 

src/main/java/envoy/event/MessageStatusChangeEvent.java

@@ -36,7 +36,7 @@ public class MessageStatusChangeEvent implements Event<Message.MessageStatus> {
 	}
 
 	/**
-	 * Initialises a {@link MessageStatusChangeEvent} through a message.
+	 * Initializes a {@link MessageStatusChangeEvent} through a message.
 	 *
 	 * @param message the message from which to build the event
 	 * @since Envoy Common v0.2-alpha