netty学习（4）:通过SpringBoot Web发送消息实现netty实现多个客户端与服务器通信

╰半夏微凉° 2023-10-13 12:51 25阅读 0赞

### 1. 基于[netty学习（3）:SpringBoot整合netty实现多个客户端与服务器通信][netty_3_SpringBoot_netty]的学习，要想通过http在netty客户端之间发送消息，需要实现spring-boot-starter-web，封装消息格式，自动调用netty客户端 ###

### 2. 封装一个简单的message，作为http发送的消息格式 ###

在父工程创建message包

package message;
    
    import com.alibaba.fastjson.JSONObject;
    import lombok.Data;
    
    import java.nio.charset.StandardCharsets;
    
    @Data
    public class Message extends JSONObject {
        
        enum MessageType {
        
            RegisterRequest,
            RegisterResponse,
    
            QueryRegisterRequest,
            QueryRegisterResponse,
    
            Request,
            Response
        }
    
        private String messageType;
    
        private String msg;
    
        public Message(String messageType, String msg) {
        
            this.messageType = messageType;
            this.msg = msg;
        }
    
    //    //序列化
    //    public byte[] toByte(JSONObject message) {
        
    //        return message.toString().getBytes(StandardCharsets.UTF_8);
    //    }
    //
    //    //反序列化
    //    public Message toMessage(String str) {
        
    //        return (Message) JSONObject.parseObject(str);
    //    }
    
        @Override
        public String toString() {
        
            return "Message{" +
                    "messageType='" + messageType + '\'' +
                    ", msg='" + msg + '\'' +
                    '}';
        }
    
        public String getMessageType() {
        
            return messageType;
        }
    
        public void setMessageType(String messageType) {
        
            this.messageType = messageType;
        }
    
        public String getMsg() {
        
            return msg;
        }
    
        public void setMsg(String msg) {
        
            this.msg = msg;
        }
    }

### 3. 子工程使用父工程的代码 ###

<?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">
        <parent>
            <artifactId>nettyTest</artifactId>
            <groupId>org.example</groupId>
            <version>1.0-SNAPSHOT</version>
        </parent>
        <modelVersion>4.0.0</modelVersion>
    
        <artifactId>client1</artifactId>
    
        <dependencies>
            <dependency>
                <groupId>org.example</groupId>
                <artifactId>nettyTest</artifactId>
                <version>1.0-SNAPSHOT</version>
            </dependency>
        </dependencies>
    
    </project>

### 4. 对client模块里面的NettyClient类改造，支持发送消息的函数sendMessage（） ###

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
    @Slf4j
    public 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);
        }
    
    //发送消息
        public void sendMessage(String message) {
        
            this.channel.writeAndFlush(message + "\r\n");
        }
    }

### 5. 创建control层，调用netty客户端发送消息 ###

package client.control;
    
    import client.netty.NettyClient;
    import message.Message;
    import org.springframework.web.bind.annotation.*;
    import javax.annotation.Resource;
    
    @RestController
    @RequestMapping("/test")
    public class NettyControl {
        
        @Resource
        private NettyClient nettyClient;
    
        @PostMapping("/msg")
        public String sendMsg(@RequestBody Message message) {
        
            this.nettyClient.sendMessage(message.getMsg());
            return message.getMsg();
        }
    }

### 6. 测试，(还不支持发送给指定的客户端,接下来要改造为指定客户端） ###

给client1发送消息  
![在这里插入图片描述][c4f191a409884b0b9e531d36f4870e2c.png]  
![在这里插入图片描述][ffb9e2bf8c794c328ca4461abfdf39ff.png_pic_center]  
client2收到消息：  
![在这里插入图片描述][6193f8a5a0b24ee18338febcac916546.png_pic_center]  
服务器：  
![在这里插入图片描述][4188610a76b6430e8d915e645ed43a58.png_pic_center]

[netty_3_SpringBoot_netty]: https://blog.csdn.net/weixin_42774617/article/details/131524243?spm=1001.2014.3001.5502
[c4f191a409884b0b9e531d36f4870e2c.png]: https://img-blog.csdnimg.cn/c4f191a409884b0b9e531d36f4870e2c.png
[ffb9e2bf8c794c328ca4461abfdf39ff.png_pic_center]: https://img-blog.csdnimg.cn/ffb9e2bf8c794c328ca4461abfdf39ff.png#pic_center
[6193f8a5a0b24ee18338febcac916546.png_pic_center]: https://img-blog.csdnimg.cn/6193f8a5a0b24ee18338febcac916546.png#pic_center
[4188610a76b6430e8d915e645ed43a58.png_pic_center]: https://img-blog.csdnimg.cn/4188610a76b6430e8d915e645ed43a58.png#pic_center