1. 创建SpringBoot父工程
创建一个SpringBoot工程，然后创建三个子模块
整体工程目录：一个server服务（netty服务器），两个client服务（netty客户端）
pom文件引入netty依赖，springboot依赖
<?xml version="1.0" encoding="UTF-8"?><project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <packaging>pom</packaging> <modules> <module>server</module> <module>client1</module> <module>client2</module> </modules> <!--继承 SpringBoot 框架的一个父项目，所有自己开发的 Spring Boot 都必须的继承--> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.2.1.RELEASE</version> <relativePath/> <!-- lookup parent from repository --> </parent> <groupId>org.example</groupId> <artifactId>nettyTest</artifactId> <version>1.0-SNAPSHOT</version> <build> <plugins> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-compiler-plugin</artifactId> <configuration> <source>8</source> <target>8</target> </configuration> </plugin> </plugins> </build> <dependencies> <!--SpringBoot 框架 web 项目起步依赖，通过该依赖自动关联其它依赖，不需要我们一个一个去添加--> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>io.netty</groupId> <artifactId>netty-all</artifactId> <version>4.1.34.Final</version> </dependency> <dependency> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> <version>1.16.18</version> </dependency> <dependency> <groupId>org.slf4j</groupId> <artifactId>slf4j-api</artifactId> </dependency> <dependency> <groupId>com.alibaba</groupId> <artifactId>fastjson</artifactId> <version>1.1.23</version> </dependency> </dependencies></project>2. 创建Netty服务器
NettySpringBootApplication
package server;import org.springframework.boot.SpringApplication;import org.springframework.boot.autoconfigure.SpringBootApplication;@SpringBootApplicationpublic class NettySpringBootApplication { public static void main(String[] args) { SpringApplication.run(NettySpringBootApplication.class, args); }}NettyServiceHandler
package server.netty;import io.netty.channel.Channel;import io.netty.channel.ChannelHandlerContext;import io.netty.channel.SimpleChannelInboundHandler;import io.netty.channel.group.ChannelGroup;import io.netty.channel.group.DefaultChannelGroup;import io.netty.util.concurrent.GlobalEventExecutor;public class NettyServiceHandler extends SimpleChannelInboundHandler<String> { private static final ChannelGroup group = new DefaultChannelGroup(GlobalEventExecutor.INSTANCE); @Override public void channelActive(ChannelHandlerContext ctx) throws Exception { // 获取到当前与服务器连接成功的channel Channel channel = ctx.channel(); group.add(channel); System.out.println(channel.remoteAddress() + " 上线," + "在线数量：" + group.size()); } @Override public void channelInactive(ChannelHandlerContext ctx) throws Exception { // 获取到当前要断开连接的Channel Channel channel = ctx.channel(); System.out.println(channel.remoteAddress() + "下线，" + "在线数量：" + group.size()); } @Override protected void channelRead0(ChannelHandlerContext ctx, String msg) throws Exception { Channel channel = ctx.channel(); System.out.println("netty客户端" + channel.remoteAddress() + "发送过来的消息:" + msg); group.forEach(ch -> { // JDK8 提供的lambda表达式 if (ch != channel) { ch.writeAndFlush(channel.remoteAddress() + "：" + msg + "/n"); } }); } public void exceptionCaught(ChannelHandlerContext channelHandlerContext, Throwable throwable) throws Exception { throwable.printStackTrace(); channelHandlerContext.close(); }}SocketInitializer
package server.netty;import io.netty.channel.ChannelInitializer;import io.netty.channel.ChannelPipeline;import io.netty.channel.socket.SocketChannel;import io.netty.handler.codec.LineBasedFrameDecoder;import io.netty.handler.codec.bytes.ByteArrayDecoder;import io.netty.handler.codec.bytes.ByteArrayEncoder;import io.netty.handler.codec.string.StringDecoder;import io.netty.handler.codec.string.StringEncoder;import org.springframework.stereotype.Component;@Componentpublic class SocketInitializer extends ChannelInitializer<SocketChannel> { @Override protected void initChannel(SocketChannel socketChannel) throws Exception { ChannelPipeline pipeline = socketChannel.pipeline();// // 添加对byte数组的编解码，netty提供了很多编解码器，你们可以根据需要选择// pipeline.addLast(new ByteArrayDecoder());// pipeline.addLast(new ByteArrayEncoder()); //添加一个基于行的解码器 pipeline.addLast(new LineBasedFrameDecoder(2048)); pipeline.addLast(new StringDecoder()); pipeline.addLast(new StringEncoder()); // 添加上自己的处理器 pipeline.addLast(new NettyServiceHandler()); }}NettyServer
package server.netty;import io.netty.bootstrap.ServerBootstrap;import io.netty.channel.ChannelOption;import io.netty.channel.nio.NioEventLoopGroup;import io.netty.channel.socket.nio.NioServerSocketChannel;import lombok.Getter;import lombok.extern.slf4j.Slf4j;import org.slf4j.Logger;import org.slf4j.LoggerFactory;import org.springframework.beans.factory.annotation.Value;import org.springframework.stereotype.Component;import javax.annotation.Resource;@Component@Slf4jpublic class NettyServer { private final static Logger logger = LoggerFactory.getLogger(NettyServer.class); @Resource private SocketInitializer socketInitializer; @Getter private ServerBootstrap serverBootstrap; /** * netty服务监听端口 */ @Value("${netty.port:6666}") private int port; /** * 主线程组数量 */ @Value("${netty.bossThread:1}") private int bossThread; /** * 启动netty服务器 */ public void start() { this.init(); this.serverBootstrap.bind(this.port); logger.info("Netty started on port: {} (TCP) with boss thread {}", this.port, this.bossThread); } /** * 初始化netty配置 */ private void init() { NioEventLoopGroup bossGroup = new NioEventLoopGroup(this.bossThread); NioEventLoopGroup workerGroup = new NioEventLoopGroup(); this.serverBootstrap = new ServerBootstrap(); this.serverBootstrap.group(bossGroup, workerGroup) // 两个线程组加入进来 .channel(NioServerSocketChannel.class) // 配置为nio类型 .option(ChannelOption.SO_BACKLOG, 128) //设置线程队列等待连接个数 .childOption(ChannelOption.SO_KEEPALIVE, true) .childHandler(this.socketInitializer); // 加入自己的初始化器 }}NettyStartListener
package server.netty;import org.springframework.boot.ApplicationArguments;import org.springframework.boot.ApplicationRunner;import org.springframework.stereotype.Component;import javax.annotation.Resource;/** * 监听Spring容器启动完成，完成后启动Netty服务器 * @author Gjing **/@Componentpublic class NettyStartListener implements ApplicationRunner { @Resource private NettyServer nettyServer; @Override public void run(ApplicationArguments args) throws Exception { this.nettyServer.start(); }}application.yml
server: port: 8000netty: port: 6666 bossThread: 13. 创建Netty客户端
Client1
package client;import org.springframework.boot.SpringApplication;import org.springframework.boot.autoconfigure.SpringBootApplication;@SpringBootApplicationpublic class Client1 { public static void main(String[] args) { SpringApplication.run(Client1.class, args); }}NettyClientHandler
package client.netty;import io.netty.channel.ChannelHandlerContext;import io.netty.channel.SimpleChannelInboundHandler;public class NettyClientHandler extends SimpleChannelInboundHandler<String> { public void channelRead0(ChannelHandlerContext channelHandlerContext, String msg) { System.out.println("收到服务端消息：" + channelHandlerContext.channel().remoteAddress() + "的消息：" + msg); } public void exceptionCaught(ChannelHandlerContext channelHandlerContext, Throwable throwable) throws Exception { channelHandlerContext.close(); }}SocketInitializer
package client.netty;import io.netty.channel.ChannelInitializer;import io.netty.channel.ChannelPipeline;import io.netty.channel.socket.SocketChannel;import io.netty.handler.codec.LineBasedFrameDecoder;import io.netty.handler.codec.string.StringDecoder;import io.netty.handler.codec.string.StringEncoder;import org.springframework.stereotype.Component;@Componentpublic class SocketInitializer extends ChannelInitializer<SocketChannel> { @Override protected void initChannel(SocketChannel socketChannel) throws Exception { ChannelPipeline pipeline = socketChannel.pipeline(); pipeline.addLast(new LineBasedFrameDecoder(2048)); pipeline.addLast(new StringDecoder()); pipeline.addLast(new StringEncoder()); pipeline.addLast(new NettyClientHandler()); //加入自己的处理器 }}NettyClient
package client.netty;import io.netty.bootstrap.Bootstrap;import io.netty.channel.Channel;import io.netty.channel.ChannelFuture;import io.netty.channel.EventLoopGroup;import io.netty.channel.nio.NioEventLoopGroup;import io.netty.channel.socket.nio.NioSocketChannel;import lombok.Getter;import lombok.extern.slf4j.Slf4j;import org.slf4j.Logger;import org.slf4j.LoggerFactory;import org.springframework.beans.factory.annotation.Value;import org.springframework.stereotype.Component;import javax.annotation.Resource;import java.io.BufferedReader;import java.io.IOException;import java.io.InputStreamReader;import java.nio.charset.StandardCharsets;@Component@Slf4jpublic class NettyClient { private final static Logger logger = LoggerFactory.getLogger(NettyClient.class); @Resource private SocketInitializer socketInitializer; @Getter private Bootstrap bootstrap; @Getter private Channel channel; /** * netty服务监听端口 */ @Value("${netty.port:6666}") private int port; @Value("${netty.host:127.0.0.1}") private String host; /** * 启动netty */ public void start() { this.init(); this.channel = this.bootstrap.connect(host, port).channel(); logger.info("Netty connect on port: {}, the host {}, the channel {}", this.port, this.host, this.channel); try { InputStreamReader is = new InputStreamReader(System.in, StandardCharsets.UTF_8); BufferedReader br = new BufferedReader(is); while (true) { System.out.println("输入："); this.channel.writeAndFlush(br.readLine() + "/r/n"); } } catch (IOException e) { e.printStackTrace(); } } /** * 初始化netty配置 */ private void init() { EventLoopGroup group = new NioEventLoopGroup(); this.bootstrap = new Bootstrap(); //设置线程组 bootstrap.group(group) .channel(NioSocketChannel.class) //设置客户端的通道实现类型 .handler(this.socketInitializer); }}NettyStartListener
package client.netty;import org.springframework.boot.ApplicationArguments;import org.springframework.boot.ApplicationRunner;import org.springframework.stereotype.Component;import javax.annotation.Resource;@Componentpublic class NettyStartListener implements ApplicationRunner { @Resource private NettyClient nettyClient; @Override public void run(ApplicationArguments args) throws Exception { this.nettyClient.start(); }}application.yml
server: port: 8001netty: port: 6666 host: "127.0.0.1"然后按照相同的方法创建client2
4. 测试
