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. */ package com.flysoloing.learning.network.netty.qotm; import io.netty.bootstrap.Bootstrap; import io.netty.buffer.Unpooled; import io.netty.channel.Channel; import io.netty.channel.ChannelOption; import io.netty.channel.EventLoopGroup; import io.netty.channel.nio.NioEventLoopGroup; import io.netty.channel.socket.DatagramPacket; import io.netty.channel.socket.nio.NioDatagramChannel; import io.netty.util.CharsetUtil; import io.netty.util.internal.SocketUtils; /** * A UDP broadcast client that asks for a quote of the moment (QOTM) to {@link QuoteOfTheMomentServer}. * * Inspired by <a href="http://docs.oracle.com/javase/tutorial/networking/datagrams/clientServer.html">the official * Java tutorial</a>. */ public final class QuoteOfTheMomentClient { static final int PORT = Integer.parseInt(System.getProperty("port", "7686")); public static void main(String[] args) throws Exception { EventLoopGroup group = new NioEventLoopGroup(); try { Bootstrap b = new Bootstrap(); b.group(group).channel(NioDatagramChannel.class).option(ChannelOption.SO_BROADCAST, true) .handler(new QuoteOfTheMomentClientHandler()); Channel ch = b.bind(0).sync().channel(); // Broadcast the QOTM request to port 8080. ch.writeAndFlush(new DatagramPacket(Unpooled.copiedBuffer("QOTM?", CharsetUtil.UTF_8), SocketUtils.socketAddress("255.255.255.255", PORT))).sync(); // QuoteOfTheMomentClientHandler will close the DatagramChannel when a // response is received. If the channel is not closed within 5 seconds, // print an error message and quit. if (!ch.closeFuture().await(5000)) { System.err.println("QOTM request timed out."); } } finally { group.shutdownGracefully(); } } }