Java tutorial
/* * Copyright 2012 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 com.thomas.netty4.websocket.server; import static io.netty.handler.codec.http.HttpHeaders.Names.CONTENT_TYPE; import static io.netty.handler.codec.http.HttpHeaders.Names.HOST; import static io.netty.handler.codec.http.HttpMethod.GET; import static io.netty.handler.codec.http.HttpResponseStatus.BAD_REQUEST; import static io.netty.handler.codec.http.HttpResponseStatus.FORBIDDEN; import static io.netty.handler.codec.http.HttpResponseStatus.NOT_FOUND; import static io.netty.handler.codec.http.HttpResponseStatus.OK; import static io.netty.handler.codec.http.HttpVersion.HTTP_1_1; import io.netty.buffer.ByteBuf; import io.netty.buffer.Unpooled; import io.netty.channel.Channel; import io.netty.channel.ChannelFuture; import io.netty.channel.ChannelFutureListener; import io.netty.channel.ChannelHandlerContext; import io.netty.channel.SimpleChannelInboundHandler; import io.netty.handler.codec.http.DefaultFullHttpResponse; import io.netty.handler.codec.http.FullHttpRequest; import io.netty.handler.codec.http.FullHttpResponse; import io.netty.handler.codec.http.HttpHeaders; import io.netty.handler.codec.http.websocketx.CloseWebSocketFrame; import io.netty.handler.codec.http.websocketx.PingWebSocketFrame; import io.netty.handler.codec.http.websocketx.PongWebSocketFrame; import io.netty.handler.codec.http.websocketx.TextWebSocketFrame; import io.netty.handler.codec.http.websocketx.WebSocketFrame; import io.netty.handler.codec.http.websocketx.WebSocketServerHandshaker; import io.netty.handler.codec.http.websocketx.WebSocketServerHandshakerFactory; import io.netty.util.CharsetUtil; import java.net.InetSocketAddress; import java.util.HashMap; import java.util.Iterator; import java.util.Map; import java.util.Map.Entry; /** * Handles handshakes and messages */ public class GxWebSocketServerHandler extends SimpleChannelInboundHandler<Object> { private static final String WEBSOCKET_PATH = "/websocket"; private WebSocketServerHandshaker handshaker; public static Map<String, Channel> channels = new HashMap<String, Channel>(); @Override public void channelRead0(ChannelHandlerContext ctx, Object msg) { if (msg instanceof FullHttpRequest) { handleHttpRequest(ctx, (FullHttpRequest) msg); } else if (msg instanceof WebSocketFrame) { handleWebSocketFrame(ctx, (WebSocketFrame) msg); } } @Override public void channelReadComplete(ChannelHandlerContext ctx) { ctx.flush(); } @Override public void channelActive(ChannelHandlerContext ctx) throws Exception { //int port = ((InetSocketAddress)ctx.channel().localAddress()).getPort(); InetSocketAddress address = (InetSocketAddress) ctx.channel().remoteAddress(); String host = address.getHostName(); int port = address.getPort(); channels.put(host + ":" + port, ctx.channel()); System.out.println("connection active, " + channels.size() + " connections counted"); } @Override public void channelUnregistered(ChannelHandlerContext ctx) throws Exception { //int port = ((InetSocketAddress)ctx.channel().localAddress()).getPort(); InetSocketAddress address = (InetSocketAddress) ctx.channel().remoteAddress(); String host = address.getHostName(); int port = address.getPort(); channels.remove(host + ":" + port); System.out.println("connection leave, " + channels.size() + " connections counted"); } private void handleHttpRequest(ChannelHandlerContext ctx, FullHttpRequest req) { // Handle a bad request. if (!req.getDecoderResult().isSuccess()) { sendHttpResponse(ctx, req, new DefaultFullHttpResponse(HTTP_1_1, BAD_REQUEST)); return; } // Allow only GET methods. if (req.getMethod() != GET) { sendHttpResponse(ctx, req, new DefaultFullHttpResponse(HTTP_1_1, FORBIDDEN)); return; } // Send the demo page and favicon.ico if ("/".equals(req.getUri())) { ByteBuf content = GxWebSocketServerIndexPage.getContent(getWebSocketLocation(req)); FullHttpResponse res = new DefaultFullHttpResponse(HTTP_1_1, OK, content); res.headers().set(CONTENT_TYPE, "text/html; charset=UTF-8"); HttpHeaders.setContentLength(res, content.readableBytes()); sendHttpResponse(ctx, req, res); return; } if ("/favicon.ico".equals(req.getUri())) { FullHttpResponse res = new DefaultFullHttpResponse(HTTP_1_1, NOT_FOUND); sendHttpResponse(ctx, req, res); return; } // Handshake WebSocketServerHandshakerFactory wsFactory = new WebSocketServerHandshakerFactory(getWebSocketLocation(req), null, true); handshaker = wsFactory.newHandshaker(req); if (handshaker == null) { WebSocketServerHandshakerFactory.sendUnsupportedVersionResponse(ctx.channel()); } else { handshaker.handshake(ctx.channel(), req); } } private void handleWebSocketFrame(ChannelHandlerContext ctx, WebSocketFrame frame) { // Check for closing frame if (frame instanceof CloseWebSocketFrame) { handshaker.close(ctx.channel(), (CloseWebSocketFrame) frame.retain()); return; } if (frame instanceof PingWebSocketFrame) { ctx.channel().write(new PongWebSocketFrame(frame.content().retain())); return; } if (!(frame instanceof TextWebSocketFrame)) { throw new UnsupportedOperationException( String.format("%s frame types not supported", frame.getClass().getName())); } // Send the uppercase string back. String message = ((TextWebSocketFrame) frame).text(); //System.err.printf("%s received %s%n", ctx.channel(), message); System.err.println("exchange:" + message); ctx.channel().write(new TextWebSocketFrame(message.toUpperCase())); broadcastWebSocketFrame(message); } private void broadcastWebSocketFrame(String message) { if (message.startsWith("producer")) { Iterator<Entry<String, Channel>> citerator = channels.entrySet().iterator(); while (citerator.hasNext()) { Entry<String, Channel> hpch = citerator.next(); String hp = hpch.getKey(); Channel channel = hpch.getValue(); if (channel == null) { channels.remove(hp); System.out.println("remove damn null channel : " + hp); System.out.println("connection leave, " + channels.size() + " connections counted"); } else if (!channel.isActive()) { channels.remove(hp); System.out.println("remove damn dead channel : " + hp); System.out.println("connection leave, " + channels.size() + " connections counted"); } else { channel.writeAndFlush(new TextWebSocketFrame(message.toUpperCase())); } } } } private static void sendHttpResponse(ChannelHandlerContext ctx, FullHttpRequest req, FullHttpResponse res) { // Generate an error page if response getStatus code is not OK (200). if (res.getStatus().code() != 200) { ByteBuf buf = Unpooled.copiedBuffer(res.getStatus().toString(), CharsetUtil.UTF_8); res.content().writeBytes(buf); buf.release(); HttpHeaders.setContentLength(res, res.content().readableBytes()); } // Send the response and close the connection if necessary. ChannelFuture f = ctx.channel().writeAndFlush(res); if (!HttpHeaders.isKeepAlive(req) || res.getStatus().code() != 200) { f.addListener(ChannelFutureListener.CLOSE); } } @Override public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) { cause.printStackTrace(); ctx.close(); } private static String getWebSocketLocation(FullHttpRequest req) { String location = req.headers().get(HOST) + WEBSOCKET_PATH; if (GxWebSocketServer.SSL) { return "wss://" + location; } else { return "ws://" + location; } } }