（java）websocket服务的两种实现方式

Java中实现WebSocket服务的常见方式有两种：使用Java EE的@ServerEndpoint注解或使用Spring框架。

1. 使用Java EE的@ServerEndpoint注解：

import javax.websocket.*;
import javax.websocket.server.ServerEndpoint;
import java.io.IOException;
import java.util.concurrent.CopyOnWriteArraySet;
 
@ServerEndpoint("/websocket")
public class WebSocketEndpoint {
    private static final CopyOnWriteArraySet<Session> sessions = new CopyOnWriteArraySet<>();
 
    @OnOpen
    public void onOpen(Session session) {
        sessions.add(session);
        System.out.println("Connected ... " + session.getId());
    }
 
    @OnClose
    public void onClose(Session session) {
        sessions.remove(session);
        System.out.println("Disconnected ... " + session.getId());
    }
 
    @OnMessage
    public void onMessage(String message, Session session) {
        System.out.println("Received message in endpoint: " + message);
        // Broadcast message to all active sessions
        for (Session s : sessions) {
            try {
                s.getBasicRemote().sendText(message);
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
 
    @OnError
    public void onError(Session session, Throwable throwable) {
        System.out.println("Error for session: " + session.getId());
        throwable.printStackTrace();
    }
}

2. 使用Spring框架：

import org.springframework.web.socket.TextMessage;
import org.springframework.web.socket.WebSocketSession;
import org.springframework.web.socket.handler.TextWebSocketHandler;
 
import java.util.concurrent.ConcurrentHashMap;
 
public class WebSocketHandler extends TextWebSocketHandler {
    private static final ConcurrentHashMap<String, WebSocketSession> sessions = new ConcurrentHashMap<>();
 
    @Override
    public void afterConnectionEstablished(WebSocketSession session) {
        sessions.put(session.getId(), session);
        System.out.println("Connected ... " + session.getId());
    }
 
    @Override
    public void afterConnectionClosed(WebSocketSession session, CloseStatus status) {
        sessions.remove(session.getId())