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 org.apache.kerby.kerberos.kdc.impl; import io.netty.bootstrap.Bootstrap; import io.netty.bootstrap.ServerBootstrap; import io.netty.channel.ChannelHandler; import io.netty.channel.ChannelInitializer; import io.netty.channel.ChannelOption; 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.NioDatagramChannel; import io.netty.channel.socket.nio.NioServerSocketChannel; import io.netty.handler.codec.LengthFieldBasedFrameDecoder; import io.netty.handler.logging.LogLevel; import io.netty.handler.logging.LoggingHandler; import io.netty.util.concurrent.DefaultEventExecutorGroup; import org.apache.kerby.kerberos.kerb.server.KdcContext; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import java.io.IOException; import java.net.InetSocketAddress; /** * A combined and mixed network server handling UDP and TCP. */ public class NettyKdcNetwork { private KdcContext kdcContext; private InetSocketAddress tcpAddress; private InetSocketAddress udpAddress; private EventLoopGroup bossGroup; private EventLoopGroup workerGroup; private EventLoopGroup group; private static final Logger LOG = LoggerFactory.getLogger(NettyKdcNetwork.class); public void init(KdcContext kdcContext) { this.kdcContext = kdcContext; // Configure the server. bossGroup = new NioEventLoopGroup(1); workerGroup = new NioEventLoopGroup(); } public void listen(InetSocketAddress tcpAddress, InetSocketAddress udpAddress) throws IOException { this.tcpAddress = tcpAddress; this.udpAddress = udpAddress; } public void start() { try { doStart(); } catch (Exception e) { LOG.error("Error occurred while starting the netty kdc network."); } } private void doStart() throws Exception { ServerBootstrap b = new ServerBootstrap(); b.group(bossGroup, workerGroup).channel(NioServerSocketChannel.class).option(ChannelOption.SO_BACKLOG, 100) .handler(new LoggingHandler(LogLevel.INFO)).childHandler(createChannelInitializer()); // Start the server. b.bind(tcpAddress.getPort()); if (udpAddress != null) { startUDPServer(); } } private void startUDPServer() { this.group = new NioEventLoopGroup(); Bootstrap b = new Bootstrap(); b.group(group).channel(NioDatagramChannel.class).option(ChannelOption.SO_BROADCAST, true) .handler((ChannelHandler) new NettyKdcUdpServerHandler(kdcContext)); b.bind(udpAddress.getPort()); } static class KrbMessageDecoder extends LengthFieldBasedFrameDecoder { public KrbMessageDecoder() { super(1 * 1024 * 1024, 0, 4, 0, 4, true); } } private ChannelInitializer<SocketChannel> createChannelInitializer() { return new ChannelInitializer<SocketChannel>() { @Override public void initChannel(SocketChannel ch) throws Exception { ChannelPipeline p = ch.pipeline(); p.addLast(new KrbMessageDecoder()); p.addLast(new DefaultEventExecutorGroup(10), //TODO: to configure. "KDC_HANDLER", new NettyKdcHandler(kdcContext)); } }; } public synchronized void stop() { // Shut down all event loops to terminate all threads. bossGroup.shutdownGracefully(); workerGroup.shutdownGracefully(); if (udpAddress != null) { group.shutdownGracefully(); } } }