import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Component;import javax.websocket.*;
import javax.websocket.server.PathParam;
import javax.websocket.server.ServerEndpoint;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;@Component
@Slf4j
@ServerEndpoint("/websocketHandler/{userId}")
public class MyWebSocketHandler {/*** 线程安全Map*/private static ConcurrentHashMap<String, Session> sessionPool = new ConcurrentHashMap<>();/*** Redis触发监听名字*/public static final String REDIS_TOPIC_NAME = "socketHandlerReport";//==========【websocket接受、推送消息等方法 —— 具体服务节点推送ws消息】========================================================================================@OnOpenpublic void onOpen(Session session, @PathParam(value = "userId") String userId) {try {sessionPool.put(userId, session);log.info("【系统 WebSocket】有新的连接，总数为:" + sessionPool.size());} catch (Exception e) {}}@OnClosepublic void onClose(@PathParam("userId") String userId) {try {sessionPool.remove(userId);log.info("【系统 WebSocket】连接断开，总数为:" + sessionPool.size());} catch (Exception e) {e.printStackTrace();}}/*** ws推送消息** @param userId* @param message*/public void pushMessage(String userId, String message) {for (Map.Entry<String, Session> item : sessionPool.entrySet()) {//userId key值= {用户id + "_"+ 登录token的md5串}if (item.getKey().contains(userId)) {Session session = item.getValue();try {//update-begin-author:taoyan date:20211012 for: websocket报错 https://gitee.com/jeecg/jeecg-boot/issues/I4C0MUsynchronized (session) {log.info("【系统 WebSocket】推送单人消息:" + message);session.getBasicRemote().sendText(message);}//update-end-author:taoyan date:20211012 for: websocket报错 https://gitee.com/jeecg/jeecg-boot/issues/I4C0MU} catch (Exception e) {log.error(e.getMessage(), e);}}}}/*** ws遍历群发消息*/public void pushMessage(String message) {try {for (Map.Entry<String, Session> item : sessionPool.entrySet()) {try {item.getValue().getAsyncRemote().sendText(message);} catch (Exception e) {log.error(e.getMessage(), e);}}log.info("【系统 WebSocket】群发消息:" + message);} catch (Exception e) {log.error(e.getMessage(), e);}}/*** ws接受客户端消息*/@OnMessagepublic void onMessage(String message, @PathParam(value = "userId") String userId) {if (!"ping".equals(message) && !WebsocketConst.CMD_TOPIC.equals(message)) {log.info("【系统 WebSocket】收到客户端消息:" + message);} else {log.debug("【系统 WebSocket】收到客户端消息:" + message);}//------------------------------------------------------------------------------
//        JSONObject obj = new JSONObject();
//        //业务类型
//        obj.put(WebsocketConst.MSG_CMD, WebsocketConst.CMD_CHECK);
//        //消息内容
//        obj.put(WebsocketConst.MSG_TXT, "心跳响应");
//        this.pushMessage(userId, obj.toJSONString());//------------------------------------------------------------------------------//--------PC端消息推送--------Session session = sessionPool.get(userId);if (session != null && session.isOpen()) {try {log.info("【websocket消息】 单点消息:" + message);session.getAsyncRemote().sendText(message);} catch (Exception e) {e.printStackTrace();}}//--------增加APP端消息推送--------Session session_app = sessionPool.get(userId + APP_SESSION_SUFFIX);if (session_app != null && session_app.isOpen()) {try {log.info("【websocket移动端消息】 单点消息:" + message);session_app.getAsyncRemote().sendText(message);} catch (Exception e) {e.printStackTrace();}}}/*** 配置错误信息处理** @param session* @param t*/@OnErrorpublic void onError(Session session, Throwable t) {log.warn("【系统 WebSocket】消息出现错误");//t.printStackTrace();}//==========【系统 WebSocket接受、推送消息等方法 —— 具体服务节点推送ws消息】========================================================================================//==========【采用redis发布订阅模式——推送消息】========================================================================================/*** 后台发送消息到redis** @param message*/public void sendMessage(String message) {//log.info("【系统 WebSocket】广播消息:" + message);
//        BaseMap baseMap = new BaseMap();
//        baseMap.put("userId", "");
//        baseMap.put("message", message);
//        jeecgRedisClient.sendMessage(REDIS_TOPIC_NAME, baseMap);}/*** 此为单点消息 redis** @param userId* @param message*/public void sendMessage(String userId, String message) {
//        BaseMap baseMap = new BaseMap();
//        baseMap.put("userId", userId);
//        baseMap.put("message", message);
//        jeecgRedisClient.sendMessage(REDIS_TOPIC_NAME, baseMap);}/*** 此为单点消息(多人) redis** @param userIds* @param message*/public void sendMessage(String[] userIds, String message) {for (String userId : userIds) {sendMessage(userId, message);}}//=======【采用redis发布订阅模式——推送消息】==========================================================================================//1.增加app端标识private String APP_SESSION_SUFFIX = "_app";public void sendOneMessage(String userId, String message) {//--------PC端消息推送--------Session session = sessionPool.get(userId);if (session != null && session.isOpen()) {try {log.info("【websocket消息】 单点消息:" + message);session.getAsyncRemote().sendText(message);} catch (Exception e) {e.printStackTrace();}}//--------增加APP端消息推送--------Session session_app = sessionPool.get(userId + APP_SESSION_SUFFIX);if (session_app != null && session_app.isOpen()) {try {log.info("【websocket移动端消息】 单点消息:" + message);session_app.getAsyncRemote().sendText(message);} catch (Exception e) {e.printStackTrace();}}}
}

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.socket.config.annotation.EnableWebSocket;
import org.springframework.web.socket.server.standard.ServerEndpointExporter;/*** 开启WebSocket支持*/
@Configuration
@EnableWebSocket
public class WebSocketConfig {@Beanpublic ServerEndpointExporter serverEndpointExporter() {return new ServerEndpointExporter();}
}

public class WebsocketConst {/*** 消息json key:cmd*/public static final String MSG_CMD = "cmd";/*** 消息json key:msgId*/public static final String MSG_ID = "msgId";/*** 消息json key:msgTxt*/public static final String MSG_TXT = "msgTxt";/*** 消息json key:userId*/public static final String MSG_USER_ID = "userId";/*** 消息json key:chat*/public static final String MSG_CHAT = "chat";/*** 消息类型 heartcheck*/public static final String CMD_CHECK = "heartcheck";/*** 消息类型 user 用户消息*/public static final String CMD_USER = "user";/*** 消息类型 topic 系统通知*/public static final String CMD_TOPIC = "topic";/*** 消息类型 email*/public static final String CMD_EMAIL = "email";/*** 消息类型 meetingsign 会议签到*/public static final String CMD_SIGN = "sign";/*** 消息类型 新闻发布/取消*/public static final String NEWS_PUBLISH = "publish";}

项目启动后遇到如下错误:

Invocation of init method failed; nested exception is java.lang.IllegalStateException: javax.websocket.server.ServerContainer not available

用IDEA启动项目，所报的异常，打jar包服务器上运行则不报，原因是spring boot内带tomcat，tomcat中的websocket会有冲突出现问题。我的解决办法：

注释掉WebSocketConfig中的

    @Beanpublic ServerEndpointExporter serverEndpointExporter() {return new ServerEndpointExporter();}