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. */ //The MIT License // //Copyright (c) 2009 Carl Bystrm // //Permission is hereby granted, free of charge, to any person obtaining a copy //of this software and associated documentation files (the "Software"), to deal //in the Software without restriction, including without limitation the rights //to use, copy, modify, merge, publish, distribute, sublicense, and/or sell //copies of the Software, and to permit persons to whom the Software is //furnished to do so, subject to the following conditions: // //The above copyright notice and this permission notice shall be included in //all copies or substantial portions of the Software. // //THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR //IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, //FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE //AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER //LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, //OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN //THE SOFTWARE. package org.radarlab.client.ws; import io.netty.channel.*; import io.netty.handler.codec.http.FullHttpResponse; import io.netty.handler.codec.http.websocketx.*; import io.netty.util.CharsetUtil; import org.apache.log4j.Logger; import org.json.JSONObject; import java.util.concurrent.TimeUnit; public class WebSocketClientHandler extends SimpleChannelInboundHandler<Object> { private static final Logger logger = Logger.getLogger(WebSocketClientHandler.class); private final WebSocketClientHandshaker handshaker; private ChannelPromise handshakeFuture; public WebSocketClientHandler(WebSocketClientHandshaker handshaker) { this.handshaker = handshaker; } public static String getMessage(Long requestId) { try { String message = RadarWebSocketClient.queues.get(requestId).poll(5, TimeUnit.SECONDS); RadarWebSocketClient.queues.remove(requestId); return message; } catch (InterruptedException e) { logger.error(e.getMessage(), e); } return null; } public ChannelFuture handshakeFuture() { return handshakeFuture; } @Override public void handlerAdded(ChannelHandlerContext ctx) { handshakeFuture = ctx.newPromise(); } @Override public void channelActive(ChannelHandlerContext ctx) { handshaker.handshake(ctx.channel()); } @Override public void channelInactive(ChannelHandlerContext ctx) { logger.info("WebSocket Client disconnected!"); ctx.close(); } @Override public void channelRead0(ChannelHandlerContext ctx, Object msg) throws Exception { Channel ch = ctx.channel(); if (!handshaker.isHandshakeComplete()) { handshaker.finishHandshake(ch, (FullHttpResponse) msg); logger.info("WebSocket Client:" + ctx.name() + " connected!"); handshakeFuture.setSuccess(); return; } if (msg instanceof FullHttpResponse) { FullHttpResponse response = (FullHttpResponse) msg; throw new IllegalStateException("Unexpected FullHttpResponse (getStatus=" + response.getStatus() + ", content=" + response.content().toString(CharsetUtil.UTF_8) + ')'); } WebSocketFrame frame = (WebSocketFrame) msg; if (frame instanceof TextWebSocketFrame) { TextWebSocketFrame textFrame = (TextWebSocketFrame) frame; String result = textFrame.text(); JSONObject json = new JSONObject(result); if (json.has("id")) { RadarWebSocketClient.queues.get(json.getLong("id")).put(result); } else { RadarWebSocketClient.subscribeQueue.offer(result); } } else if (frame instanceof PongWebSocketFrame) { System.out.println("WebSocket Client received pong"); } else if (frame instanceof CloseWebSocketFrame) { System.out.println("WebSocket Client received closing"); ch.close(); } } @Override public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) { logger.error("Handler caught exception: " + cause.getMessage(), cause); if (!handshakeFuture.isDone()) { handshakeFuture.setFailure(cause); } ctx.close(); } }