Java tutorial
/** * Copyright (c) 2015, WSO2 Inc. (http://www.wso2.org) All Rights Reserved. * * WSO2 Inc. 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 org.wso2.carbon.websocket.transport; import io.netty.bootstrap.Bootstrap; import io.netty.channel.Channel; import io.netty.channel.ChannelFuture; import io.netty.channel.ChannelFutureListener; import io.netty.channel.ChannelInitializer; import io.netty.channel.ChannelPipeline; import io.netty.channel.EventLoopGroup; import io.netty.channel.nio.NioEventLoopGroup; import io.netty.channel.socket.SocketChannel; import io.netty.channel.socket.nio.NioSocketChannel; import io.netty.handler.codec.http.DefaultHttpHeaders; import io.netty.handler.codec.http.HttpClientCodec; import io.netty.handler.codec.http.HttpObjectAggregator; import io.netty.handler.codec.http.websocketx.WebSocketClientHandshakerFactory; import io.netty.handler.codec.http.websocketx.WebSocketFrameAggregator; import io.netty.handler.codec.http.websocketx.WebSocketVersion; import io.netty.handler.ssl.SslContext; import io.netty.handler.ssl.SslContextBuilder; import org.apache.axiom.om.OMElement; import org.apache.axis2.description.Parameter; import org.apache.axis2.description.TransportOutDescription; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.wso2.carbon.websocket.transport.utils.SSLUtil; import javax.net.ssl.SSLException; import javax.xml.namespace.QName; import java.net.URI; import java.util.concurrent.ConcurrentHashMap; public class WebsocketConnectionFactory { private static final Log log = LogFactory.getLog(WebsocketConnectionFactory.class); private static WebsocketConnectionFactory instance = null; private final TransportOutDescription transportOut; private ConcurrentHashMap<String, ConcurrentHashMap<String, WebSocketClientHandler>> channelHandlerPool = new ConcurrentHashMap<String, ConcurrentHashMap<String, WebSocketClientHandler>>(); public WebsocketConnectionFactory(TransportOutDescription transportOut) { this.transportOut = transportOut; } public static WebsocketConnectionFactory getInstance(TransportOutDescription transportOut) { if (instance == null) { instance = new WebsocketConnectionFactory(transportOut); } return instance; } public WebSocketClientHandler getChannelHandler(final URI uri, final String sourceIdentifier, final boolean handshakePresent, final String dispatchSequence, final String dispatchErrorSequence, final String contentType) throws InterruptedException { WebSocketClientHandler channelHandler; if (handshakePresent) { channelHandler = cacheNewConnection(uri, sourceIdentifier, dispatchSequence, dispatchErrorSequence, contentType); } else { channelHandler = getChannelHandlerFromPool(sourceIdentifier, getClientHandlerIdentifier(uri)); if (channelHandler == null) { channelHandler = cacheNewConnection(uri, sourceIdentifier, dispatchSequence, dispatchErrorSequence, contentType); } } channelHandler.handshakeFuture().sync(); return channelHandler; } public String getClientHandlerIdentifier(final URI uri) { final String host = uri.getHost() == null ? "127.0.0.1" : uri.getHost(); final int port = uri.getPort(); final String subscriberPath = uri.getPath(); return host.concat(String.valueOf(port)).concat(subscriberPath); } public WebSocketClientHandler cacheNewConnection(final URI uri, final String sourceIdentifier, String dispatchSequence, String dispatchErrorSequence, String contentType) { if (log.isDebugEnabled()) { log.debug("Creating a Connection for the specified WS endpoint."); } final WebSocketClientHandler handler; try { String scheme = uri.getScheme() == null ? WebsocketConstants.WS : uri.getScheme(); final String host = uri.getHost() == null ? "127.0.0.1" : uri.getHost(); final int port = uri.getPort(); if (!WebsocketConstants.WS.equalsIgnoreCase(scheme) && !WebsocketConstants.WSS.equalsIgnoreCase(scheme)) { return null; } final boolean ssl = WebsocketConstants.WSS.equalsIgnoreCase(scheme); final SslContext sslCtx; if (ssl) { Parameter trustParam = transportOut.getParameter(WebsocketConstants.TRUST_STORE_CONFIG_ELEMENT); OMElement tsEle = null; if (trustParam != null) { tsEle = trustParam.getParameterElement().getFirstElement(); } final String location = tsEle .getFirstChildWithName(new QName(WebsocketConstants.TRUST_STORE_LOCATION)).getText(); final String storePassword = tsEle .getFirstChildWithName(new QName(WebsocketConstants.TRUST_STORE_PASSWORD)).getText(); sslCtx = SslContextBuilder.forClient() .trustManager(SSLUtil.createTrustmanager(location, storePassword)).build(); } else { sslCtx = null; } if (sourceIdentifier.equals(WebsocketConstants.UNIVERSAL_SOURCE_IDENTIFIER)) { Parameter dispatchParam = transportOut .getParameter(WebsocketConstants.WEBSOCKET_OUTFLOW_DISPATCH_SEQUENCE); if (dispatchParam != null) { dispatchSequence = dispatchParam.getParameterElement().getText(); } Parameter errorParam = transportOut .getParameter(WebsocketConstants.WEBSOCKET_OUTFLOW_DISPATCH_FAULT_SEQUENCE); if (errorParam != null) { dispatchErrorSequence = errorParam.getParameterElement().getText(); } } final EventLoopGroup group = new NioEventLoopGroup(); handler = new WebSocketClientHandler( WebSocketClientHandshakerFactory.newHandshaker(uri, WebSocketVersion.V13, contentType != null ? SubprotocolBuilderUtil.contentTypeToSyanapeSubprotocol(contentType) : null, false, new DefaultHttpHeaders())); Bootstrap b = new Bootstrap(); b.group(group).channel(NioSocketChannel.class).handler(new ChannelInitializer<SocketChannel>() { @Override protected void initChannel(SocketChannel ch) { ChannelPipeline p = ch.pipeline(); if (sslCtx != null) { p.addLast(sslCtx.newHandler(ch.alloc(), host, port)); } p.addLast(new HttpClientCodec(), new HttpObjectAggregator(8192), new WebSocketFrameAggregator(Integer.MAX_VALUE), handler); } }); Channel ch = b.connect(uri.getHost(), port).sync().channel(); ch.closeFuture().addListener(new ChannelFutureListener() { @Override public void operationComplete(ChannelFuture channelFuture) throws Exception { group.shutdownGracefully(); removeChannelHandler(sourceIdentifier, getClientHandlerIdentifier(uri)); } }); handler.setDispatchSequence(dispatchSequence); handler.setDispatchErrorSequence(dispatchErrorSequence); addChannelHandler(sourceIdentifier, getClientHandlerIdentifier(uri), handler); return handler; } catch (InterruptedException e) { log.error("Interruption occured while connecting to the remote WS endpoint", e); } catch (SSLException e) { log.error("Error occurred while building the SSL context fo WSS endpoint", e); } return null; } public void addChannelHandler(String sourceIdentifier, String clientIdentifier, WebSocketClientHandler clientHandler) { ConcurrentHashMap<String, WebSocketClientHandler> handlerMap = channelHandlerPool.get(sourceIdentifier); if (handlerMap == null) { handlerMap = new ConcurrentHashMap<String, WebSocketClientHandler>(); handlerMap.put(clientIdentifier, clientHandler); channelHandlerPool.put(sourceIdentifier, handlerMap); } else { handlerMap.put(clientIdentifier, clientHandler); } } public WebSocketClientHandler getChannelHandlerFromPool(String sourceIdentifier, String clientIdentifier) { ConcurrentHashMap<String, WebSocketClientHandler> handlerMap = channelHandlerPool.get(sourceIdentifier); if (handlerMap == null) { return null; } else { return handlerMap.get(clientIdentifier); } } public void removeChannelHandler(String sourceIdentifier, String clientIdentifier) { ConcurrentHashMap<String, WebSocketClientHandler> handlerMap = channelHandlerPool.get(sourceIdentifier); handlerMap.remove(clientIdentifier); } }