Java example source code file (WebSocketProtocolHandler.java)

This example Java source code file (WebSocketProtocolHandler.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

exception, list, messagetomessagedecoder, override, pingwebsocketframe, pongwebsocketframe, throwable, util, websocketprotocolhandler

The WebSocketProtocolHandler.java Java example source code

/*
 * Copyright 2013 The Netty Project
 *
 * The Netty Project licenses this file to you under the Apache License,
 * version 2.0 (the "License"); you may not use this file except in compliance
 * with the License. You may obtain a copy of the License at:
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations
 * under the License.
 */
package io.netty.handler.codec.http.websocketx;


import io.netty.channel.ChannelHandlerContext;
import io.netty.handler.codec.MessageToMessageDecoder;

import java.util.List;

abstract class WebSocketProtocolHandler extends MessageToMessageDecoder<WebSocketFrame> {
    @Override
    protected void decode(ChannelHandlerContext ctx, WebSocketFrame frame, List<Object> out) throws Exception {
        if (frame instanceof PingWebSocketFrame) {
            frame.content().retain();
            ctx.channel().writeAndFlush(new PongWebSocketFrame(frame.content()));
            return;
        }
        if (frame instanceof PongWebSocketFrame) {
            // Pong frames need to get ignored
            return;
        }

        out.add(frame.retain());
    }

    @Override
    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
        ctx.close();
    }
}