1.WebSocketConfig

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

@Configuration
public class WebSocketConfig {
    @Bean
    public ServerEndpointExporter serverEndpointExporter() {
        
 
return new ServerEndpointExporter();
    }

}

2.WebSocketServer

import java.io.IOException;
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.ServerEndpoint;


import org.springframework.stereotype.Component;
 
//@ServerEndpoint("/websocket/{user}")
@ServerEndpoint(value = "/websocket")
@Component
public class WebSocketServer {
    //靜態變數，用來記錄當前線上連線數。應該把它設計成執行緒安全的。
    private static int onlineCount = 0;
    //concurrent包的執行緒安全Set，用來存放每個客戶端對應的MyWebSocket物件。
    private static CopyOnWriteArraySet<WebSocketServer> webSocketSet = new
 
 CopyOnWriteArraySet<WebSocketServer>();

    //與某個客戶端的連線會話，需要通過它來給客戶端傳送資料
    private Session session;

    /**
     * 連線建立成功呼叫的方法*/
    @OnOpen
    public void onOpen(Session session) {
        this.session = session;
        webSocketSet.add(this);     //加入set中
        addOnlineCount();           //線上數加1
        System.out.println("Connected ... " + session.getId());
        System.out.println("有新連線加入！當前線上人數為" + getOnlineCount());
        try {
            sendMessage("連線成功");
        } catch (IOException e) {
            System.out.println("websocket IO異常");
        }
    }
    //    //連線開啟時執行
    //    @OnOpen
    //    public void onOpen(@PathParam("user") String user, Session session) {
    //        currentUser = user;
    //        System.out.println("Connected ... " + session.getId());
    //    }

    /**
     * 連線關閉呼叫的方法
     */
    @OnClose
    public void onClose() {
        webSocketSet.remove(this);  //從set中刪除
        subOnlineCount();           //線上數減1
        System.out.println("有一連線關閉！當前線上人數為" + getOnlineCount());
    }

    /**
     * 收到客戶端訊息後呼叫的方法
     *
     * @param message 客戶端傳送過來的訊息*/
    @OnMessage
    public void onMessage(String message, Session session) throws IOException {
        System.out.println("來自客戶端的訊息:" + message);
        System.out.println("來自客戶端 ... " + session.getId());

        session.getBasicRemote().sendText("1111");

    }

    /**
     *
     * @param session
     * @param error
     */
    @OnError
    public void onError(Session session, Throwable error) {
        System.out.println("發生錯誤");
        error.printStackTrace();
    }


    public void sendMessage(String message) throws IOException {
        System.out.println(this.session);
        this.session.getBasicRemote().sendText(message);
    }


    /**
     * 群發自定義訊息
     * */
    public static void sendInfo(String message) throws IOException {
        System.out.println(message);
        for (WebSocketServer item : webSocketSet) {
            try {
                item.sendMessage(message);
            } catch (IOException e) {
                continue;
            }
        }
    }

    public static synchronized int getOnlineCount() {
        return onlineCount;
    }

    public static synchronized void addOnlineCount() {
        WebSocketServer.onlineCount++;
    }

    public static synchronized void subOnlineCount() {
        WebSocketServer.onlineCount--;
    }
}