netty websocket协议开发
websocket的好处我们就不用多说了，就是用于解决长连接、服务推送等需要的一种技术。
以下我们来看一个例子:
1 package com.ming.netty.http.websocket; 2 3 import java.net.InetSocketAddress; 4 5 import io.netty.bootstrap.ServerBootstrap; 6 import io.netty.channel.ChannelFuture; 7 import io.netty.channel.ChannelInitializer; 8 import io.netty.channel.ChannelOption; 9 import io.netty.channel.ChannelPipeline; 10 import io.netty.channel.EventLoopGroup; 11 import io.netty.channel.nio.NioEventLoopGroup; 12 import io.netty.channel.socket.SocketChannel; 13 import io.netty.channel.socket.nio.NioServerSocketChannel; 14 import io.netty.handler.codec.http.HttpObjectAggregator; 15 import io.netty.handler.codec.http.HttpServerCodec; 16 import io.netty.handler.codec.http.websocketx.WebSocketServerProtocolHandler; 17 import io.netty.handler.stream.ChunkedWriteHandler; 18 19 public class WebSocketServer { 20 21 22 23 public static void main(String[] args) { 24 new WebSocketServer().run("127.0.0.1", 8500); 25 } 26 27 28 public void run(String addr,int port){ 29 EventLoopGroup bossGroup = new NioEventLoopGroup(); 30 EventLoopGroup workerGroup = new NioEventLoopGroup(); 31 try { 32 ServerBootstrap b=new ServerBootstrap(); 33 b.group(bossGroup, workerGroup) 34 .channel(NioServerSocketChannel.class) 35 .option(ChannelOption.SO_BACKLOG, 128) 36 .childOption(ChannelOption.SO_KEEPALIVE, true) 37 .childHandler(new WebSocketServerHandlerInitializer()); 38 39 ChannelFuture f=b.bind(new InetSocketAddress(addr, port)).sync(); 40 System.out.println("启动服务器:"+f.channel().localAddress()); 41 //等等服务器端监听端口关闭 42 f.channel().closeFuture().sync(); 43 44 } catch (Exception e) { 45 e.printStackTrace(); 46 }finally{ 47 bossGroup.shutdownGracefully(); 48 workerGroup.shutdownGracefully(); 49 } 50 } 51 52 protected class WebSocketServerHandlerInitializer extends ChannelInitializer<SocketChannel>{ 53 54 @Override 55 protected void initChannel(SocketChannel ch) throws Exception { 56 ChannelPipeline pipeline = ch.pipeline(); 57 pipeline.addLast(new HttpServerCodec()); 58 pipeline.addLast(new HttpObjectAggregator(64*1024)); 59 pipeline.addLast(new ChunkedWriteHandler()); 60 pipeline.addLast(new HttpRequestHandler("/ws")); 61 pipeline.addLast(new WebSocketServerProtocolHandler("/ws")); 62 pipeline.addLast(new TextWebSocketFrameHandler()); 63 } 64 65 } 66 }
1 package com.ming.netty.http.websocket; 2 3 import io.netty.channel.Channel; 4 import io.netty.channel.ChannelFuture; 5 import io.netty.channel.ChannelFutureListener; 6 import io.netty.channel.ChannelHandlerContext; 7 import io.netty.channel.DefaultFileRegion; 8 import io.netty.channel.SimpleChannelInboundHandler; 9 import io.netty.handler.codec.http.DefaultFullHttpResponse; 10 import io.netty.handler.codec.http.DefaultHttpResponse; 11 import io.netty.handler.codec.http.FullHttpRequest; 12 import io.netty.handler.codec.http.FullHttpResponse; 13 import io.netty.handler.codec.http.HttpHeaders; 14 import io.netty.handler.codec.http.HttpResponse; 15 import io.netty.handler.codec.http.HttpResponseStatus; 16 import io.netty.handler.codec.http.HttpVersion; 17 import io.netty.handler.codec.http.LastHttpContent; 18 import io.netty.handler.ssl.SslHandler; 19 import io.netty.handler.stream.ChunkedNioFile; 20 21 import java.io.File; 22 import java.io.IOException; 23 import java.io.RandomAccessFile; 24 import java.net.URISyntaxException; 25 import java.net.URL; 26 27 public class HttpRequestHandler extends SimpleChannelInboundHandler<FullHttpRequest> { 28 29 private final String wsUri; 30 private static final File INDEX; 31 32 // static HTTP request handling operation. 33 static { 34 URL location = HttpRequestHandler.class.getProtectionDomain().getCodeSource().getLocation(); 35 try { 36 String path = location.toURI() + "WebSocketClient.html"; 37 path = !path.contains("file:") ? path : path.substring(5); 38 INDEX = new File("D:\\javaPro\\workspace\\NettyTest\\resources\\WebsocketChatClient.html"); 39 } catch (URISyntaxException e) { 40 throw new IllegalStateException("Unable to locate WebsocketChatClient.html", e); 41 } 42 } 43 44 45 public HttpRequestHandler(String wsUri) { 46 this.wsUri = wsUri; 47 } 48 49 50 51 52 @Override 53 protected void messageReceived(ChannelHandlerContext ctx, FullHttpRequest request) throws Exception { 54 channelRead(ctx,request); 55 56 } 57 58 59 60 61 public void channelRead(ChannelHandlerContext ctx, FullHttpRequest request) 62 throws Exception { 63 if (wsUri.equalsIgnoreCase(request.getUri())) { 64 ctx.fireChannelRead(request.retain()); 65 } else { 66 if (HttpHeaders.is100ContinueExpected(request)) { 67 send100Continue(ctx); 68 } 69 70 RandomAccessFile file = new RandomAccessFile(INDEX, "r"); 71 HttpResponse response = new DefaultHttpResponse( 72 request.getProtocolVersion(), HttpResponseStatus.OK); 73 response.headers().set(HttpHeaders.Names.CONTENT_TYPE, 74 "text/html; charset=UTF-8"); 75 76 boolean keepAlive = HttpHeaders.isKeepAlive(request); 77 if (keepAlive) { 78 response.headers().set(HttpHeaders.Names.CONTENT_LENGTH, file.length()); 79 response.headers().set(HttpHeaders.Names.CONNECTION, HttpHeaders.Values.KEEP_ALIVE); 80 } 81 ctx.write(response); 82 83 if (ctx.pipeline().get(SslHandler.class) == null) { 84 ctx.write(new DefaultFileRegion(file.getChannel(), 0, file.length())); 85 } else { 86 ctx.write(new ChunkedNioFile(file.getChannel())); 87 } 88 ChannelFuture future = ctx.writeAndFlush(LastHttpContent.EMPTY_LAST_CONTENT); 89 if (!keepAlive) { 90 future.addListener(ChannelFutureListener.CLOSE); 91 } 92 93 file.close(); 94 } 95 } 96 97 private static void send100Continue(ChannelHandlerContext ctx) { 98 FullHttpResponse response = new DefaultFullHttpResponse( 99 HttpVersion.HTTP_1_1, HttpResponseStatus.CONTINUE); 100 ctx.writeAndFlush(response); 101 } 102 103 @Override 104 public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) 105 throws Exception { 106 Channel incoming = ctx.channel(); 107 System.out.println("Client:" + incoming.remoteAddress() + "异常"); 108 109 // 当出现异常就关闭连接 110 cause.printStackTrace(); 111 ctx.close(); 112 } 113 114 }
1 package com.ming.netty.http.websocket; 2 3 import io.netty.channel.Channel; 4 import io.netty.channel.ChannelHandlerContext; 5 import io.netty.channel.SimpleChannelInboundHandler; 6 import io.netty.channel.group.ChannelGroup; 7 import io.netty.channel.group.DefaultChannelGroup; 8 import io.netty.handler.codec.http.websocketx.TextWebSocketFrame; 9 import io.netty.util.concurrent.GlobalEventExecutor; 10 11 public class TextWebSocketFrameHandler extends SimpleChannelInboundHandler<TextWebSocketFrame> { 12 13 public static ChannelGroup channels = new DefaultChannelGroup(GlobalEventExecutor.INSTANCE); 14 15 16 17 @Override 18 public void channelActive(ChannelHandlerContext ctx) throws Exception { 19 Channel incoming = ctx.channel(); 20 System.out.println("Client:" + incoming.remoteAddress() + "在线"); 21 } 22 23 24 25 @Override 26 public void channelInactive(ChannelHandlerContext ctx) throws Exception { 27 Channel incoming = ctx.channel(); 28 System.out.println("Client:" + incoming.remoteAddress() + "掉线"); 29 } 30 31 32 @Override 33 public void handlerAdded(ChannelHandlerContext ctx) throws Exception { 34 Channel incoming = ctx.channel(); 35 for (Channel channel : channels) { 36 channel.writeAndFlush(new TextWebSocketFrame("[SERVER] - " + incoming.remoteAddress() + " 加入")); 37 } 38 channels.add(ctx.channel()); 39 System.out.println("Client:" + incoming.remoteAddress() + "加入"); 40 } 41 42 43 44 @Override 45 public void handlerRemoved(ChannelHandlerContext ctx) throws Exception { 46 Channel incoming = ctx.channel(); 47 for (Channel channel : channels) { 48 channel.writeAndFlush(new TextWebSocketFrame("[SERVER] - " + incoming.remoteAddress() + " 离开")); 49 } 50 System.out.println("Client:" + incoming.remoteAddress() + "离开"); 51 channels.remove(ctx.channel()); 52 } 53 54 55 56 57 58 59 @Override 60 protected void messageReceived(ChannelHandlerContext ctx, TextWebSocketFrame msg) throws Exception { 61 Channel incoming = ctx.channel(); 62 for (Channel channel : channels) { 63 if (channel != incoming) { 64 //channel.writeAndFlush(new TextWebSocketFrame("[" + incoming.remoteAddress() + "]" + msg.text())); 65 } else { 66 //返送给指定的 67 channel.writeAndFlush(new TextWebSocketFrame("[服务器端返回]：" + msg.text())); 68 69 70 //output current message to context. 71 StringBuffer sb = new StringBuffer(); 72 sb.append(incoming.remoteAddress()).append("->").append(msg.text()); 73 System.out.println(sb.toString()); 74 } 75 } 76 77 } 78 79 80 81 @Override 82 public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception { 83 Channel incoming = ctx.channel(); 84 System.out.println("Client:" + incoming.remoteAddress() + "异常"); 85 // 当出现异常就关闭连接 86 cause.printStackTrace(); 87 ctx.close(); 88 } 89 90 91 92 93 94 95 96 }
1 <!DOCTYPE html> 2 <html> 3 <head> 4 <meta charset="UTF-8"> 5 <title>WebSocket Chat</title> 6 </head> 7 <body> 8 <script type="text/javascript"> 9 var socket; 10 if (!window.WebSocket) { 11 window.WebSocket = window.MozWebSocket; 12 } 13 if (window.WebSocket) { 14 socket = new WebSocket("ws://127.0.0.1:8500/ws"); 15 socket.onmessage = function(event) { 16 var ta = document.getElementById('responseText'); 17 ta.value = ta.value + '\n' + event.data 18 }; 19 socket.onopen = function(event) { 20 var ta = document.getElementById('responseText'); 21 ta.value = "连接开启!"; 22 }; 23 socket.onclose = function(event) { 24 var ta = document.getElementById('responseText'); 25 ta.value = ta.value + "连接被关闭"; 26 }; 27 } else { 28 alert("你的浏览器不支持 WebSocket！"); 29 } 30 31 function send(message) { 32 if (!window.WebSocket) { 33 return; 34 } 35 if (socket.readyState == WebSocket.OPEN) { 36 socket.send(message); 37 } else { 38 alert("连接没有开启."); 39 } 40 } 41 </script> 42 <form onsubmit="return false;"> 43 <h3>WebSocket 聊天室：</h3> 44 <textarea id="responseText" style="width: 500px; height: 300px;"></textarea> 45 <br> 46 <input type="text" name="message" style="width: 300px" value="Welcome to www.waylau.com"> 47 <input type="button" value="发送消息" onclick="send(this.form.message.value)"> 48 <input type="button" onclick="javascript:document.getElementById('responseText').value=''" value="清空聊天记录"> 49 </form> 50 <br> 51 <br> 52 53 </body> 54 </html>
运行服务器，然后在浏览器输入：127.0.0.1:8500 就可以看见一个简单的聊天室效果了.
