Netty的第一个例子

import io.netty.bootstrap.ServerBootstrap; import io.netty.channel.ChannelFuture; import io.netty.channel.ChannelInitializer; import io.netty.channel.ChannelOption; import io.netty.channel.EventLoopGroup; import io.netty.channel.nio.NioEventLoopGroup; import io.netty.channel.socket.SocketChannel; import io.netty.channel.socket.nio.NioServerSocketChannel; public class TimeServer { public void bind(int port) throws Exception { EventLoopGroup bossGroup = new NioEventLoopGroup(); EventLoopGroup workerGroup = new NioEventLoopGroup(); try { ServerBootstrap serverBootstrap = new ServerBootstrap(); serverBootstrap.group(bossGroup, workerGroup) .channel(NioServerSocketChannel.class) .option(ChannelOption.SO_BACKLOG, 1024) .childHandler(new ChildChannelHandler()); //绑定端口，同步等待成功 ChannelFuture future = serverBootstrap.bind(port).sync(); //等待服务端监听端口关闭 future.channel().closeFuture().sync(); } catch (Exception e) { e.printStackTrace(); } finally { //优雅退出 bossGroup.shutdownGracefully(); workerGroup.shutdownGracefully(); } } private class ChildChannelHandler extends ChannelInitializer<SocketChannel> { @Override protected void initChannel(SocketChannel socketChannel) throws Exception { socketChannel.pipeline().addLast(new TimeServerHandler()); } } public static void main(String[] args) throws Exception { int port = 8080; if (args != null && args.length > 0) { try { port = Integer.parseInt(args[0]); } catch (Exception e) { e.printStackTrace(); } } new TimeServer().bind(port); } }

 

TimeServerHandler

 

import io.netty.buffer.ByteBuf; import io.netty.buffer.Unpooled; import io.netty.channel.ChannelHandlerAdapter; import io.netty.channel.ChannelHandlerContext; import io.netty.channel.ChannelInboundHandlerAdapter; import java.sql.Timestamp; import java.text.DateFormat; import java.text.SimpleDateFormat; import java.util.Date; public class TimeServerHandler extends ChannelInboundHandlerAdapter { public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception { ByteBuf buf = (ByteBuf) msg; byte[] req = new byte[buf.readableBytes()]; buf.readBytes(req); String body = new String(req, "UTF-8"); System.out.println("The time server receive order:" + body); String currentTime = "QUERY TIME ORDER".equalsIgnoreCase(body) ? new Date(System.currentTimeMillis()).toString() : "BAD ORDER"; ByteBuf resp = Unpooled.copiedBuffer(currentTime.getBytes()); ctx.write(resp); ctx.flush(); } @Override public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception { super.exceptionCaught(ctx, cause); } }

 

 

TimeClient

  import io.netty.bootstrap.Bootstrap; import io.netty.channel.ChannelFuture; import io.netty.channel.ChannelInitializer; import io.netty.channel.ChannelOption; import io.netty.channel.EventLoopGroup; import io.netty.channel.nio.NioEventLoopGroup; import io.netty.channel.socket.SocketChannel; import io.netty.channel.socket.nio.NioSocketChannel; public class TimeClient { public void connect(int port, String host) throws Exception { //配置客户端NIO线程组 EventLoopGroup eventLoopGroup = new NioEventLoopGroup(); try { Bootstrap bootstrap = new Bootstrap(); bootstrap.group(eventLoopGroup) .channel(NioSocketChannel.class) .option(ChannelOption.SO_BACKLOG, 1024) .handler(new ChannelInitializer<SocketChannel>() { @Override protected void initChannel(SocketChannel socketChannel) throws Exception { socketChannel.pipeline().addLast(new TimeClientHandler()); } }); //发起异步链接操作 ChannelFuture channelFuture = bootstrap.connect(host, port).sync(); //等待客户端链路关闭 channelFuture.channel().closeFuture().sync(); } catch (Exception e) { e.printStackTrace(); } finally { //优雅退出，释放NIO线程组 eventLoopGroup.shutdownGracefully(); } } public static void main(String[] args) throws Exception { int port = 8080; if (args != null && args.length > 0) { try { port = Integer.parseInt(args[0]); } catch (Exception e) { //采用默认值 e.printStackTrace(); } } new TimeClient().connect(port, "127.0.0.1"); }     TimeClientHandler Time import io.netty.buffer.ByteBuf; import io.netty.buffer.Unpooled; import io.netty.channel.ChannelHandlerAdapter; import io.netty.channel.ChannelHandlerContext; import io.netty.channel.ChannelInboundHandlerAdapter; public class TimeClientHandler extends ChannelInboundHandlerAdapter { private ByteBuf firstMessage; public TimeClientHandler() { byte[] req = "QUERY TIME ORDER".getBytes(); this.firstMessage = Unpooled.buffer(req.length); this.firstMessage.writeBytes(req); } public void channelActive(ChannelHandlerContext ctx) { ctx.writeAndFlush(this.firstMessage); } public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception { ByteBuf byteBuf = (ByteBuf)msg; byte[] req = new byte[byteBuf.readableBytes()]; byteBuf.readBytes(req); String body = new String(req, "UTF-8"); System.out.println("Now is " + body); } @Override public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception { super.exceptionCaught(ctx, cause); } }  

越努力，越幸运，欢迎关注我的个人技术公众号

深耕java领域，技术专家，博客专家，联系我请去 微信公众号：波哥的技术积累，回复“资料”，会有意外惊喜，包含面试题，系统架构图，并发包源码分析等资料，而且波哥老师的视频教程【Java并发包源码分析(JDK1.8)】即将免费，https://edu.csdn.net/course/detail/22039，大家有对JUC源码感兴趣的，可以去学习，有问题微信联系，会及时解答！