Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF 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 spark.network.netty; import io.netty.bootstrap.Bootstrap; import io.netty.channel.Channel; import io.netty.channel.ChannelFuture; import io.netty.channel.ChannelFutureListener; import io.netty.channel.ChannelOption; import io.netty.channel.oio.OioEventLoopGroup; import io.netty.channel.socket.oio.OioSocketChannel; import org.slf4j.Logger; import org.slf4j.LoggerFactory; class FileClient { private Logger LOG = LoggerFactory.getLogger(this.getClass().getName()); private FileClientHandler handler = null; private Channel channel = null; private Bootstrap bootstrap = null; private int connectTimeout = 60 * 1000; // 1 min public FileClient(FileClientHandler handler, int connectTimeout) { this.handler = handler; this.connectTimeout = connectTimeout; } public void init() { bootstrap = new Bootstrap(); bootstrap.group(new OioEventLoopGroup()).channel(OioSocketChannel.class) .option(ChannelOption.SO_KEEPALIVE, true).option(ChannelOption.TCP_NODELAY, true) .option(ChannelOption.CONNECT_TIMEOUT_MILLIS, connectTimeout) .handler(new FileClientChannelInitializer(handler)); } public void connect(String host, int port) { try { // Start the connection attempt. channel = bootstrap.connect(host, port).sync().channel(); // ChannelFuture cf = channel.closeFuture(); //cf.addListener(new ChannelCloseListener(this)); } catch (InterruptedException e) { close(); } } public void waitForClose() { try { channel.closeFuture().sync(); } catch (InterruptedException e) { LOG.warn("FileClient interrupted", e); } } public void sendRequest(String file) { //assert(file == null); //assert(channel == null); channel.write(file + "\r\n"); } public void close() { if (channel != null) { channel.close(); channel = null; } if (bootstrap != null) { bootstrap.shutdown(); bootstrap = null; } } }