netty4.0.23 初学的demo
例子共4个文件,用到的jar包有:
netty-all-4.0.23.Final.jar
log4j.jar (apache的)
commons-logging-1.1.1.jar(apache的)
文件 TcpServerHandler
package test.netty; import org.apache.log4j.Logger; import io.netty.channel.ChannelHandlerContext; import io.netty.channel.SimpleChannelInboundHandler; public class TcpServerHandler extends SimpleChannelInboundHandler<Object> { private static final Logger logger = Logger.getLogger(TcpServerHandler.class); @Override protected void channelRead0(ChannelHandlerContext ctx, Object msg) throws Exception { logger.info("SERVER接收到消息:"+msg); ctx.channel().writeAndFlush("yes, server is accepted you ,nice !"+msg); } @Override public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception { logger.warn("Unexpected exception from downstream.", cause); ctx.close(); } }
文件 TcpServer
package test.netty; import org.apache.log4j.Logger; import io.netty.bootstrap.ServerBootstrap; import io.netty.channel.ChannelInitializer; 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.NioServerSocketChannel; import io.netty.handler.codec.LengthFieldBasedFrameDecoder; import io.netty.handler.codec.LengthFieldPrepender; import io.netty.handler.codec.string.StringDecoder; import io.netty.handler.codec.string.StringEncoder; import io.netty.util.CharsetUtil; public class TcpServer { private static final Logger logger = Logger.getLogger(TcpServer.class); private static final String IP = "127.0.0.1"; private static final int PORT = 9999; /**用于分配处理业务线程的线程组个数 */ protected static final int BIZGROUPSIZE = Runtime.getRuntime().availableProcessors()*2; //默认 /** 业务出现线程大小*/ protected static final int BIZTHREADSIZE = 4; /* * NioEventLoopGroup实际上就是个线程池, * NioEventLoopGroup在后台启动了n个NioEventLoop来处理Channel事件, * 每一个NioEventLoop负责处理m个Channel, * NioEventLoopGroup从NioEventLoop数组里挨个取出NioEventLoop来处理Channel */ private static final EventLoopGroup bossGroup = new NioEventLoopGroup(BIZGROUPSIZE); private static final EventLoopGroup workerGroup = new NioEventLoopGroup(BIZTHREADSIZE); protected static void run() throws Exception { ServerBootstrap b = new ServerBootstrap(); b.group(bossGroup, workerGroup); b.channel(NioServerSocketChannel.class); b.childHandler(new ChannelInitializer<SocketChannel>() { @Override public void initChannel(SocketChannel ch) throws Exception { ChannelPipeline pipeline = ch.pipeline(); pipeline.addLast("frameDecoder", new LengthFieldBasedFrameDecoder(Integer.MAX_VALUE, 0, 4, 0, 4)); pipeline.addLast("frameEncoder", new LengthFieldPrepender(4)); pipeline.addLast("decoder", new StringDecoder(CharsetUtil.UTF_8)); pipeline.addLast("encoder", new StringEncoder(CharsetUtil.UTF_8)); pipeline.addLast(new TcpServerHandler()); } }); b.bind(IP, PORT).sync(); logger.info("TCP服务器已启动"); } protected static void shutdown() { workerGroup.shutdownGracefully(); bossGroup.shutdownGracefully(); } public static void main(String[] args) throws Exception { logger.info("开始启动TCP服务器..."); TcpServer.run(); // TcpServer.shutdown(); } }
文件 TcpClientHandler
package test.netty; import org.apache.log4j.Logger; import io.netty.channel.ChannelHandlerContext; import io.netty.channel.SimpleChannelInboundHandler; public class TcpClientHandler extends SimpleChannelInboundHandler<Object> { private static final Logger logger = Logger.getLogger(TcpClientHandler.class); @Override protected void channelRead0(ChannelHandlerContext ctx, Object msg) throws Exception { //messageReceived方法,名称很别扭,像是一个内部方法. logger.info("client接收到服务器返回的消息:"+msg); } }
文件 TcpClient
package test.netty; import io.netty.bootstrap.Bootstrap; import io.netty.channel.Channel; 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.nio.NioSocketChannel; import io.netty.handler.codec.LengthFieldBasedFrameDecoder; import io.netty.handler.codec.LengthFieldPrepender; import io.netty.handler.codec.string.StringDecoder; import io.netty.handler.codec.string.StringEncoder; import io.netty.util.CharsetUtil; import org.apache.log4j.Logger; public class TcpClient { private static final Logger logger = Logger.getLogger(TcpClient.class); public static String HOST = "127.0.0.1"; public static int PORT = 9999; public static Bootstrap bootstrap = getBootstrap(); public static Channel channel = getChannel(HOST,PORT); /** * 初始化Bootstrap * @return */ public static final Bootstrap getBootstrap(){ EventLoopGroup group = new NioEventLoopGroup(); Bootstrap b = new Bootstrap(); b.group(group).channel(NioSocketChannel.class); b.handler(new ChannelInitializer<Channel>() { @Override protected void initChannel(Channel ch) throws Exception { ChannelPipeline pipeline = ch.pipeline(); pipeline.addLast("frameDecoder", new LengthFieldBasedFrameDecoder(Integer.MAX_VALUE, 0, 4, 0, 4)); pipeline.addLast("frameEncoder", new LengthFieldPrepender(4)); pipeline.addLast("decoder", new StringDecoder(CharsetUtil.UTF_8)); pipeline.addLast("encoder", new StringEncoder(CharsetUtil.UTF_8)); pipeline.addLast("handler", new TcpClientHandler()); } }); b.option(ChannelOption.SO_KEEPALIVE, true); return b; } public static final Channel getChannel(String host,int port){ Channel channel = null; try { channel = bootstrap.connect(host, port).sync().channel(); } catch (Exception e) { logger.error(String.format("连接Server(IP[%s],PORT[%s])失败", host,port),e); return null; } return channel; } public static void sendMsg(String msg) throws Exception { if(channel!=null){ channel.writeAndFlush(msg).sync(); }else{ logger.warn("消息发送失败,连接尚未建立!"); } } public static void main(String[] args) throws Exception { try { long t0 = System.nanoTime(); for (int i = 0; i < 100000; i++) { TcpClient.sendMsg(i+"你好1"); } long t1 = System.nanoTime(); System.out.println((t1-t0)/1000000.0); } catch (Exception e) { e.printStackTrace(); } } }