Java tutorial
package com.pokersu.server; /* * 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. */ 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.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.FullHttpResponse; import io.netty.handler.codec.http.HttpHeaders; import io.netty.handler.codec.http.HttpRequest; import io.netty.handler.codec.http.websocketx.BinaryWebSocketFrame; 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 org.slf4j.Logger; import org.slf4j.LoggerFactory; /** * Handles handshakes and messages */ public abstract class WebSocketServerHandler extends SimpleChannelInboundHandler<Object> { protected static Logger log = LoggerFactory.getLogger(WebSocketServerHandler.class); private static boolean useSsl = false; private static final String WEBSOCKET_PATH = "/websocket"; private WebSocketServerHandshaker handshaker; @Override protected void channelRead0(ChannelHandlerContext ctx, Object msg) throws Exception { System.out.println("Received Request: " + msg); log.debug("Received Request: {}", msg); if (msg instanceof WebSocketFrame) { handleWebSocketFrame(ctx, (WebSocketFrame) msg); } else if (msg instanceof HttpRequest) { handleHttpRequest(ctx, (HttpRequest) msg); } else log.warn("Not support handle: {}", msg.getClass()); } @Override public void channelReadComplete(ChannelHandlerContext ctx) { ctx.flush(); } private void handleHttpRequest(ChannelHandlerContext ctx, HttpRequest 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 = WebSocketServerIndexPage.getContent(getWebSocketLocation(req)); FullHttpResponse res = new DefaultFullHttpResponse(HTTP_1_1, OK, content); res.headers().set(HttpHeaders.Names.CONTENT_TYPE, "text/html; charset=UTF-8"); // HttpUtil.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) { if (frame instanceof BinaryWebSocketFrame) { //Handle BinaryWebSocketFrame handleBinaryWebSocketFrame(ctx, (BinaryWebSocketFrame) frame); } else if (frame instanceof TextWebSocketFrame) { //Handle TextWebSocketFrame //Send the uppercase string back. String request = ((TextWebSocketFrame) frame).text(); log.info("Received %{}", request); ctx.channel().write(new TextWebSocketFrame(request.toUpperCase())); } else if (frame instanceof CloseWebSocketFrame) { // Check for closing frame handshaker.close(ctx.channel(), (CloseWebSocketFrame) frame.retain()); } else if (frame instanceof PingWebSocketFrame) { //Ping ctx.channel().write(new PongWebSocketFrame(frame.content().retain())); } else { throw new UnsupportedOperationException( String.format("%s frame types not supported", frame.getClass().getName())); } } private void handleBinaryWebSocketFrame(ChannelHandlerContext ctx, BinaryWebSocketFrame frame) { try { } catch (Exception e) { log.error(e.getMessage(), e); } } private static void sendHttpResponse(ChannelHandlerContext ctx, HttpRequest 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(); // HttpUtil.setContentLength(res, res.content().readableBytes()); } // Send the response and close the connection if necessary. ChannelFuture f = ctx.channel().writeAndFlush(res); if (/*!HttpUtil.isKeepAlive(req) || */ res.getStatus().code() != 200) { f.addListener(ChannelFutureListener.CLOSE); } } @Override public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) { log.warn(cause.getMessage(), cause); log.warn("Closed channel: {}", ctx.channel().remoteAddress()); ctx.close(); } @Override public void channelInactive(ChannelHandlerContext ctx) throws Exception { super.channelInactive(ctx); } private static String getWebSocketLocation(HttpRequest req) { String location = req.headers().get(HttpHeaders.Names.HOST) + WEBSOCKET_PATH; if (useSsl) { return "wss://" + location; } else { return "ws://" + location; } } }