414479 - Add WebSocketPingPongListener for those that want PING/PONG payload data

+ Adding WebSocketPingPongListener and example case

jetty-websocket/websocket-api/src/main/java/org/eclipse/jetty/websocket/api/WebSocketPingPongListener.java

@@ -0,0 +1,43 @@
+//
+//  ========================================================================
+//  Copyright (c) 1995-2015 Mort Bay Consulting Pty. Ltd.
+//  ------------------------------------------------------------------------
+//  All rights reserved. This program and the accompanying materials
+//  are made available under the terms of the Eclipse Public License v1.0
+//  and Apache License v2.0 which accompanies this distribution.
+//
+//      The Eclipse Public License is available at
+//      http://www.eclipse.org/legal/epl-v10.html
+//
+//      The Apache License v2.0 is available at
+//      http://www.opensource.org/licenses/apache2.0.php
+//
+//  You may elect to redistribute this code under either of these licenses.
+//  ========================================================================
+//
+
+package org.eclipse.jetty.websocket.api;
+
+import java.nio.ByteBuffer;
+
+/**
+ * WebSocket PING/PONG Listener interface for incoming WebSocket PING/PONG frames.
+ */
+public interface WebSocketPingPongListener extends WebSocketConnectionListener
+{
+    /**
+     * A WebSocket PING has been received.
+     * 
+     * @param payload
+     *            the ping payload
+     */
+    void onWebSocketPing(ByteBuffer payload);
+
+    /**
+     * A WebSocket PONG has been received.
+     * 
+     * @param payload
+     *            the pong payload
+     */
+    void onWebSocketPong(ByteBuffer payload);
+}

jetty-websocket/websocket-common/src/test/java/examples/ListenerPingPongSocket.java

@@ -0,0 +1,60 @@
+//
+//  ========================================================================
+//  Copyright (c) 1995-2015 Mort Bay Consulting Pty. Ltd.
+//  ------------------------------------------------------------------------
+//  All rights reserved. This program and the accompanying materials
+//  are made available under the terms of the Eclipse Public License v1.0
+//  and Apache License v2.0 which accompanies this distribution.
+//
+//      The Eclipse Public License is available at
+//      http://www.eclipse.org/legal/epl-v10.html
+//
+//      The Apache License v2.0 is available at
+//      http://www.opensource.org/licenses/apache2.0.php
+//
+//  You may elect to redistribute this code under either of these licenses.
+//  ========================================================================
+//
+
+package examples;
+
+import java.nio.ByteBuffer;
+
+import org.eclipse.jetty.websocket.api.Session;
+import org.eclipse.jetty.websocket.api.WebSocketPingPongListener;
+import org.eclipse.jetty.websocket.common.events.EventCapture;
+
+public class ListenerPingPongSocket implements WebSocketPingPongListener
+{
+    public EventCapture capture = new EventCapture();
+
+    @Override
+    public void onWebSocketClose(int statusCode, String reason)
+    {
+        capture.add("onWebSocketClose(%d, %s)",statusCode,capture.q(reason));
+    }
+
+    @Override
+    public void onWebSocketConnect(Session session)
+    {
+        capture.add("onWebSocketConnect(%s)",session);
+    }
+
+    @Override
+    public void onWebSocketError(Throwable cause)
+    {
+        capture.add("onWebSocketError((%s) %s)",cause.getClass().getSimpleName(),cause.getMessage());
+    }
+
+    @Override
+    public void onWebSocketPing(ByteBuffer payload)
+    {
+        capture.add("onWebSocketPing(%d)",payload.remaining());
+    }
+
+    @Override
+    public void onWebSocketPong(ByteBuffer payload)
+    {
+        capture.add("onWebSocketPong(%d)",payload.remaining());
+    }
+}