本篇文章小编给大家分享一下Java实战之用springboot+netty实现简单的一对一聊天代码示例，文章代码介绍的很详细，小编觉得挺不错的，现在分享给大家供大家参考，有需要的小伙伴们可以来看看。

一、引入pom

    4.0.0
 
    com.chat.info
    chat-server
    1.0-SNAPSHOT
 
    
        org.springframework.boot
        spring-boot-starter-parent
        2.1.4.RELEASE
         
    
    
        UTF-8
        1.8
    
 
    
        
        
            org.springframework.boot
            spring-boot-starter-web
        
 
        
            io.netty
            netty-all
            4.1.33.Final
        
 
        
            org.projectlombok
            lombok
        
        
        
            com.alibaba
            fastjson
            1.2.56
        
        
        
            org.springframework.boot
            spring-boot-starter-thymeleaf
        
    
 
 
    
        
            
                org.springframework.boot
                spring-boot-maven-plugin
            
        
    

二、创建netty服务端

package com.chat.server;
 
import io.netty.bootstrap.ServerBootstrap;
import io.netty.channel.ChannelFuture;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.nio.NioServerSocketChannel;
import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Component;
 
import javax.annotation.PostConstruct;
import javax.annotation.PreDestroy;
 
@Component
@Slf4j
public class ChatServer {
 
    private EventLoopGroup bossGroup;
    private EventLoopGroup workGroup;
 
    private void run() throws Exception {
        log.info("开始启动聊天服务器");
        bossGroup = new NioEventLoopGroup(1);
        workGroup = new NioEventLoopGroup();
        try {
            ServerBootstrap serverBootstrap = new ServerBootstrap();
            serverBootstrap.group(bossGroup, workGroup)
                    .channel(NioServerSocketChannel.class)
                    .childHandler(new ChatServerInitializer());
            //启动服务器
            ChannelFuture channelFuture = serverBootstrap.bind(7000).sync();
            log.info("开始启动聊天服务器结束");
            channelFuture.channel().closeFuture().sync();
 
        } finally {
            bossGroup.shutdownGracefully();
            workGroup.shutdownGracefully();
        }
 
    }
 
    /**
     * 初始化服务器
     */
    @PostConstruct()
    public void init() {
        new Thread(() -> {
            try {
                run();
            } catch (Exception e) {
                e.printStackTrace();
            }
        }).start();
    }
 
 
    @PreDestroy
    public void destroy() throws InterruptedException {
        if (bossGroup != null) {
            bossGroup.shutdownGracefully().sync();
        }
        if (workGroup != null) {
            workGroup.shutdownGracefully().sync();
        }
    }
}

package com.chat.server;
 
import io.netty.channel.ChannelInitializer;
import io.netty.channel.ChannelPipeline;
import io.netty.channel.socket.SocketChannel;
import io.netty.handler.codec.http.HttpObjectAggregator;
import io.netty.handler.codec.http.HttpServerCodec;
import io.netty.handler.codec.http.websocketx.WebSocketServerProtocolHandler;
import io.netty.handler.stream.ChunkedWriteHandler;
 
public class ChatServerInitializer extends ChannelInitializer {
    @Override
    protected void initChannel(SocketChannel socketChannel) throws Exception {
        ChannelPipeline pipeline = socketChannel.pipeline();
        //使用http的编码器和解码器
        pipeline.addLast(new HttpServerCodec());
        //添加块处理器
        pipeline.addLast(new ChunkedWriteHandler());
 
        pipeline.addLast(new HttpObjectAggregator(8192));
 
        pipeline.addLast(new WebSocketServerProtocolHandler("/chat"));
        //自定义handler,处理业务逻辑
        pipeline.addLast(new ChatServerHandler());
 
 
    }
}

package com.chat.server;
 
import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
import com.chat.config.ChatConfig;
import io.netty.channel.Channel;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.SimpleChannelInboundHandler;
import io.netty.handler.codec.http.websocketx.TextWebSocketFrame;
import io.netty.util.AttributeKey;
import lombok.extern.slf4j.Slf4j;
 
import java.time.LocalDateTime;
 
@Slf4j
public class ChatServerHandler extends SimpleChannelInboundHandler {
    @Override
    protected void channelRead0(ChannelHandlerContext channelHandlerContext, TextWebSocketFrame textWebSocketFrame) throws Exception {
        //传过来的是json字符串
        String text = textWebSocketFrame.text();
        JSONObject jsonObject = JSON.parseObject(text);
        //获取到发送人的用户id
        Object msg = jsonObject.get("msg");
        String userId = (String) jsonObject.get("userId");
        Channel channel = channelHandlerContext.channel();
        if (msg == null) {
            //说明是第一次登录上来连接，还没有开始进行聊天，将uid加到map里面
            register(userId, channel);
        } else {
            //有消息了,开始聊天了
            sendMsg(msg, userId);
        }
 
    }
 
    /**
     * 第一次登录进来
     *
     * @param userId
     * @param channel
     */
    private void register(String userId, Channel channel) {
        if (!ChatConfig.concurrentHashMap.containsKey(userId)) { //没有指定的userId
            ChatConfig.concurrentHashMap.put(userId, channel);
            // 将用户ID作为自定义属性加入到channel中，方便随时channel中获取用户ID
            AttributeKey key = AttributeKey.valueOf("userId");
            channel.attr(key).setIfAbsent(userId);
        }
    }
 
    /**
     * 开发发送消息，进行聊天
     *
     * @param msg
     * @param userId
     */
    private void sendMsg(Object msg, String userId) {
        Channel channel1 = ChatConfig.concurrentHashMap.get(userId);
        if (channel1 != null) {
            channel1.writeAndFlush(new TextWebSocketFrame("服务器时间" + LocalDateTime.now() + " " + msg));
        }
    }
 
 
    /**
     * 一旦客户端连接上来，该方法被执行
     *
     * @param ctx
     * @throws Exception
     */
    @Override
    public void handlerAdded(ChannelHandlerContext ctx) throws Exception {
        log.info("handlerAdded 被调用" + ctx.channel().id().asLongText());
    }
 
    /**
     * 断开连接，需要移除用户
     *
     * @param ctx
     * @throws Exception
     */
    @Override
    public void handlerRemoved(ChannelHandlerContext ctx) throws Exception {
        removeUserId(ctx);
    }
 
    /**
     * 移除用户
     *
     * @param ctx
     */
    private void removeUserId(ChannelHandlerContext ctx) {
        Channel channel = ctx.channel();
        AttributeKey key = AttributeKey.valueOf("userId");
        String userId = channel.attr(key).get();
        ChatConfig.concurrentHashMap.remove(userId);
        log.info("用户下线,userId：{}", userId);
    }
 
    /**
     * 处理移除，关闭通道
     *
     * @param ctx
     * @param cause
     * @throws Exception
     */
    @Override
    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
        ctx.close();
    }
}

三、存储用户channel的map

package com.chat.config;
 
import io.netty.channel.Channel;
 
import java.util.concurrent.ConcurrentHashMap;
 
public class ChatConfig {
 
    public static ConcurrentHashMap concurrentHashMap = new ConcurrentHashMap();
 
 
}

四、客户端html

五、controller模拟用户登录以及要发送信息给谁

package com.chat.controller;
 
 
import com.chat.config.ChatConfig;
import io.netty.channel.Channel;
import io.netty.handler.codec.http.websocketx.TextWebSocketFrame;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestParam;
@Controller
public class ChatController {
 
    @GetMapping("login")
    public String login(Model model, @RequestParam("userId") String userId, @RequestParam("sendId") String sendId) {
        model.addAttribute("userId", userId);
        model.addAttribute("sendId", sendId);
        return "chat";
    }
 
    @GetMapping("sendMsg")
    public String login(@RequestParam("sendId") String sendId) throws InterruptedException {
        while (true) {
            Channel channel = ChatConfig.concurrentHashMap.get(sendId);
            if (channel != null) {
                channel.writeAndFlush(new TextWebSocketFrame("test"));
                Thread.sleep(1000);
            }
        }
 
    }
 
}

六、测试

登录成功要发消息给bbb

登录成功要发消息给aaa