Spring boot使用websocket实现在线聊天

maven依赖

		<dependency>
			<groupId>org.springframework.bootgroupId>
			<artifactId>spring-boot-starter-webartifactId>
		dependency>
		<dependency>
			<groupId>org.springframework.bootgroupId>
			<artifactId>spring-boot-starterartifactId>
		dependency>
		<dependency>
			<groupId>org.springframework.bootgroupId>
			<artifactId>spring-boot-starter-websocketartifactId>
		dependency>
		<dependency>
			<groupId>org.springframework.bootgroupId>
			<artifactId>spring-boot-starter-thymeleafartifactId>
		dependency>
		<dependency>
			<groupId>org.projectlombokgroupId>
			<artifactId>lombokartifactId>
		dependency>
		<dependency>
			<groupId>cn.hutoolgroupId>
			<artifactId>hutool-allartifactId>
			<version>5.8.26version>
		dependency>

Java 类

WebSocket 配置

package com.zpjiang.chat;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.socket.server.standard.ServerEndpointExporter;

@Configuration
public class WebSocketConfig {
   
    /**
     * 	注入ServerEndpointExporter，
     * 	这个bean会自动注册使用了@ServerEndpoint注解声明的Websocket endpoint
     */
    @Bean
    public ServerEndpointExporter serverEndpointExporter() {
   
        return new ServerEndpointExporter();
    }
    
}

WebSocket 接口入径（ws://localhost:8087/socket/websocket/userId）

package com.zpjiang.chat;

import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.CopyOnWriteArraySet;

import javax.websocket.OnClose;
import javax.websocket.OnError;
import javax.websocket.OnMessage;
import javax.websocket.OnOpen;
import javax.websocket.Session;
import javax.websocket.server.PathParam;
import javax.websocket.server.ServerEndpoint;

import org.springframework.stereotype.Component;

import cn.hutool.json.JSONUtil;
import lombok.extern.slf4j.Slf4j;

@Component
@Slf4j
@ServerEndpoint("/websocket/{userId}") // 接口路径  ws://localhost:8087/socket/websocket/userId;
public class WebSocket {
   

	// 与某个客户端的连接会话，需要通过它来给客户端发送数据
	private Session session;
	/**
	 * 用户ID
	 */
	private String userId;

	// concurrent包的线程安全Set，用来存放每个客户端对应的MyWebSocket对象。
	// 虽然@Component默认是单例模式的，但springboot还是会为每个websocket连接初始化一个bean，所以可以用一个静态set保存起来。
	// 注：底下WebSocket是当前类名
	private static CopyOnWriteArraySet<WebSocket> webSockets = new CopyOnWriteArraySet<>();
	// 用来存在线连接用户信息
	private static ConcurrentHashMap