1. 編寫服務端代碼

編寫業務邏輯：讀取到客戶端的消息時候，打印客戶端消息，并給客戶端回復一條消息

import io.netty.bootstrap.ServerBootstrap; import io.netty.channel.ChannelFuture; import io.netty.channel.ChannelInitializer; 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 DemoNettyServer {public void bind(int port) throws Exception {// 主線程組EventLoopGroup bossGroup = new NioEventLoopGroup();// 從線程組EventLoopGroup workerGroup = new NioEventLoopGroup();try {// netty服務器啟動類ServerBootstrap serverBootstrap = new ServerBootstrap();serverBootstrap.group(bossGroup, workerGroup) //綁定兩個線程組// 用于構造socketchannel工廠.channel(NioServerSocketChannel.class) //指定NIO的模式.childHandler(new ChannelInitializer<SocketChannel>() { // 子處理器，用于處理workerGroupprotected void initChannel(SocketChannel socketChannel) throws Exception {socketChannel.pipeline().addLast(new DemoNettyServerHandler());}});// 啟動server，綁定端口ChannelFuture channelFuture = serverBootstrap.bind(8088).sync();System.out.println("server start");// 監聽關閉的channel，等待服務器 socket 關閉 。設置位同步方式channelFuture.channel().closeFuture().sync();System.out.println("server close");} finally {//退出線程組bossGroup.shutdownGracefully();workerGroup.shutdownGracefully();}}public static void main(String[] args) throws Exception {int port = 8080;new DemoNettyServer().bind(port);}} import io.netty.buffer.ByteBuf; import io.netty.channel.ChannelHandlerContext; import io.netty.channel.ChannelInboundHandlerAdapter;public class DemoNettyServerHandler extends ChannelInboundHandlerAdapter {/*** 本方法用于讀取客戶端發送的信息*/@Overridepublic void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {System.out.println("收到來自客服端的一條消息");ByteBuf result = (ByteBuf) msg;byte[] bytesMsg = new byte[result.readableBytes()];// msg中存儲的是ByteBuf類型的數據，把數據讀取到byte[]中result.readBytes(bytesMsg);String resultStr = new String(bytesMsg);// 接收并打印客戶端的信息System.out.println("客服端內容:" + resultStr);// 釋放資源，這行很關鍵result.release();// 向客戶端發送消息String response = "我是server，我已經收到你的消息： " + resultStr;// 在當前場景下，發送的數據必須轉換成ByteBuf數組ByteBuf encoded = ctx.alloc().buffer(4 * response.length());encoded.writeBytes(response.getBytes());ctx.write(encoded);ctx.flush();}/*** 本方法用作處理異常*/@Overridepublic void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {// 當出現異常就關閉連接cause.printStackTrace();ctx.close();}/*** 信息獲取完畢后操作*/@Overridepublic void channelReadComplete(ChannelHandlerContext ctx) throws Exception {ctx.flush();}}

2. 編寫客戶端代碼

編寫業務邏輯：獲取用戶輸入，連接服務端，發送消息，讀取服務端消息，關閉連接。

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;import java.util.Scanner;public class DemoNettyClient {public void connect(String host, int port) throws Exception {EventLoopGroup worker = new NioEventLoopGroup();try {// 客戶端啟動類程序Bootstrap bootstrap = new Bootstrap();/***EventLoop的組*/bootstrap.group(worker);/*** 用于構造socketchannel工廠*/bootstrap.channel(NioSocketChannel.class);/**設置選項* 參數：Socket的標準參數（key，value），可自行百度保持呼吸，不要斷氣！* */bootstrap.option(ChannelOption.SO_KEEPALIVE, true);/*** 自定義客戶端Handle（客戶端在這里搞事情）*/bootstrap.handler(new ChannelInitializer<SocketChannel>() {@Overridepublic void initChannel(SocketChannel ch) throws Exception {ch.pipeline().addFirst(new DemoNettyClientHandler());}});/** 開啟客戶端監聽，連接到遠程節點，阻塞等待直到連接完成*/ChannelFuture channelFuture = bootstrap.connect(host, port).sync();/**阻塞等待數據，直到channel關閉(客戶端關閉)*/channelFuture.channel().closeFuture().sync();} finally {worker.shutdownGracefully();}}public static void main(String[] args) throws Exception {while (true){Scanner content = new Scanner(System.in);System.out.print("請輸入您要發送的內容: ");Meesage.CLIENT_MESSAGE = content.nextLine();DemoNettyClient client = new DemoNettyClient();client.connect("127.0.0.1", 8088);}}} import io.netty.buffer.ByteBuf; import io.netty.channel.ChannelHandlerContext; import io.netty.channel.ChannelInboundHandlerAdapter;public class DemoNettyClientHandler extends ChannelInboundHandlerAdapter {/*** 服務端發過來消息時調用*/@Overridepublic void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {System.out.println("收到來自服務端的一條消息");ByteBuf result = (ByteBuf) msg;byte[] result1 = new byte[result.readableBytes()];result.readBytes(result1);System.out.println(new String(result1));result.release();//關閉連接ctx.close();}/*** 異常時調用*/@Overridepublic void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {cause.printStackTrace();ctx.close();}/*** 連接到服務器調用*/@Overridepublic void channelActive(ChannelHandlerContext ctx) throws Exception {String msg = Meesage.CLIENT_MESSAGE;ByteBuf encoded = ctx.alloc().buffer(4 * msg.length());encoded.writeBytes(msg.getBytes());ctx.write(encoded);ctx.flush();}} public class Meesage {public static String CLIENT_MESSAGE = "";public static String SERVER_MESSAGE = ""; }

3. 結果分析

客服端截圖（手動輸入消息）

服務端消息

總結

以上是生活随笔為你收集整理的socket 收不到netty客户端消息_Netty开发 —— 首个demo学习的全部內容，希望文章能夠幫你解決所遇到的問題。

如果覺得生活随笔網站內容還不錯，歡迎將生活随笔推薦給好友。