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 com.github.sparkfy.network.server; import com.github.sparkfy.network.TransportContext; import com.github.sparkfy.network.util.IOMode; import com.github.sparkfy.network.util.NettyUtils; import com.github.sparkfy.network.util.TransportConf; import com.github.sparkfy.util.JavaUtils; import com.google.common.base.Preconditions; import com.google.common.collect.Lists; import io.netty.bootstrap.ServerBootstrap; import io.netty.buffer.PooledByteBufAllocator; import io.netty.channel.ChannelFuture; import io.netty.channel.ChannelInitializer; import io.netty.channel.ChannelOption; import io.netty.channel.EventLoopGroup; import io.netty.channel.socket.SocketChannel; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import java.io.Closeable; import java.net.InetSocketAddress; import java.util.List; import java.util.concurrent.TimeUnit; /** * Server for the efficient, low-level streaming service. */ public class TransportServer implements Closeable { private final Logger logger = LoggerFactory.getLogger(TransportServer.class); private final TransportContext context; private final TransportConf conf; private final RpcHandler appRpcHandler; private final List<TransportServerBootstrap> bootstraps; private ServerBootstrap bootstrap; private ChannelFuture channelFuture; private int port = -1; /** * Creates a TransportServer that binds to the given host and the given port, or to any available * if 0. If you don't want to bind to any special host, set "hostToBind" to null. * */ public TransportServer(TransportContext context, String hostToBind, int portToBind, RpcHandler appRpcHandler, List<TransportServerBootstrap> bootstraps) { this.context = context; this.conf = context.getConf(); this.appRpcHandler = appRpcHandler; this.bootstraps = Lists.newArrayList(Preconditions.checkNotNull(bootstraps)); try { init(hostToBind, portToBind); } catch (RuntimeException e) { JavaUtils.closeQuietly(this); throw e; } } public int getPort() { if (port == -1) { throw new IllegalStateException("Server not initialized"); } return port; } private void init(String hostToBind, int portToBind) { IOMode ioMode = IOMode.valueOf(conf.ioMode()); EventLoopGroup bossGroup = NettyUtils.createEventLoop(ioMode, conf.serverThreads(), "shuffle-server"); EventLoopGroup workerGroup = bossGroup; PooledByteBufAllocator allocator = NettyUtils.createPooledByteBufAllocator(conf.preferDirectBufs(), true /* allowCache */, conf.serverThreads()); bootstrap = new ServerBootstrap().group(bossGroup, workerGroup) .channel(NettyUtils.getServerChannelClass(ioMode)).option(ChannelOption.ALLOCATOR, allocator) .childOption(ChannelOption.ALLOCATOR, allocator); if (conf.backLog() > 0) { bootstrap.option(ChannelOption.SO_BACKLOG, conf.backLog()); } if (conf.receiveBuf() > 0) { bootstrap.childOption(ChannelOption.SO_RCVBUF, conf.receiveBuf()); } if (conf.sendBuf() > 0) { bootstrap.childOption(ChannelOption.SO_SNDBUF, conf.sendBuf()); } bootstrap.childHandler(new ChannelInitializer<SocketChannel>() { @Override protected void initChannel(SocketChannel ch) throws Exception { RpcHandler rpcHandler = appRpcHandler; for (TransportServerBootstrap bootstrap : bootstraps) { rpcHandler = bootstrap.doBootstrap(ch, rpcHandler); } context.initializePipeline(ch, rpcHandler); } }); InetSocketAddress address = hostToBind == null ? new InetSocketAddress(portToBind) : new InetSocketAddress(hostToBind, portToBind); channelFuture = bootstrap.bind(address); channelFuture.syncUninterruptibly(); port = ((InetSocketAddress) channelFuture.channel().localAddress()).getPort(); logger.debug("Shuffle server started on port :" + port); } @Override public void close() { if (channelFuture != null) { // close is a local operation and should finish within milliseconds; timeout just to be safe channelFuture.channel().close().awaitUninterruptibly(10, TimeUnit.SECONDS); channelFuture = null; } if (bootstrap != null && bootstrap.group() != null) { bootstrap.group().shutdownGracefully(); } if (bootstrap != null && bootstrap.childGroup() != null) { bootstrap.childGroup().shutdownGracefully(); } bootstrap = null; } public void sync() throws InterruptedException { channelFuture.channel().closeFuture().sync(); } }