Java tutorial
/* * Copyright 2012 Brad Anderson * * The Franz 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.mapr.franz.netty; import io.netty.bootstrap.Bootstrap; import io.netty.channel.ChannelFuture; import io.netty.channel.ChannelInitializer; import io.netty.channel.ChannelOption; import io.netty.channel.socket.SocketChannel; import io.netty.channel.socket.nio.NioEventLoopGroup; import io.netty.channel.socket.nio.NioSocketChannel; import io.netty.handler.logging.LogLevel; import io.netty.handler.logging.LoggingHandler; import java.net.InetSocketAddress; /** * Sends one message when a connection is open and echoes back any received * data to the server. Simply put, the echo client initiates the ping-pong * traffic between the echo client and server by sending the first message to * the server. */ public class FranzClient { private final String host; private final int port; private final int firstMessageSize; public FranzClient(String host, int port, int firstMessageSize) { this.host = host; this.port = port; this.firstMessageSize = firstMessageSize; } public void run() throws Exception { // Configure the client. Bootstrap b = new Bootstrap(); try { b.group(new NioEventLoopGroup()).channel(NioSocketChannel.class).option(ChannelOption.TCP_NODELAY, true) .remoteAddress(new InetSocketAddress(host, port)) .handler(new ChannelInitializer<SocketChannel>() { @Override public void initChannel(SocketChannel ch) throws Exception { ch.pipeline().addLast(new LoggingHandler(LogLevel.INFO), new FranzClientHandler(firstMessageSize)); } }); // Start the client. ChannelFuture f = b.connect().sync(); // Wait until the connection is closed. f.channel().closeFuture().sync(); } finally { // Shut down the event loop to terminate all threads. b.shutdown(); } } public static void main(String[] args) throws Exception { // Print usage if no argument is specified. if (args.length < 2 || args.length > 3) { System.err.println( "Usage: " + FranzClient.class.getSimpleName() + " <host> <port> [<first message size>]"); return; } // Parse options. final String host = args[0]; final int port = Integer.parseInt(args[1]); final int firstMessageSize; if (args.length == 3) { firstMessageSize = Integer.parseInt(args[2]); } else { firstMessageSize = 256; } new FranzClient(host, port, firstMessageSize).run(); } }