WebSocket

@ServerEndpoint("/websocket")
public class WebSocketTest {

    private static Set<Session> clients = Collections.synchronizedSet(new HashSet<Session>());

    static{
        TimerTask timerTask = new MyTimerTask();
        //running timer task as daemon thread
        Timer timer = new Timer(true);
        timer.scheduleAtFixedRate(timerTask, 0, 5*1000);
    }

    @OnMessage
    public void onMessage(String message, Session session) throws IOException {

        synchronized(clients){
            // Iterate over the connected sessions and broadcast the received message
            if(!message.equals("pong")){
                for(Session client : clients){
                    if (!client.equals(session)){
                        client.getBasicRemote().sendText(message);
                    }
                }
            }
        }
    }

    @OnOpen
    public void onOpen (Session session) {
        // Add session to the connected sessions set
        clients.add(session);
    }

    @OnClose
    public void onClose (Session session) {
        // Remove session from the connected sessions set
        clients.remove(session);
    }


    public static void notifyClients(String message) throws IOException {

        synchronized(clients){
            // Iterate over the connected sessions and broadcast the received message
            for(Session client : clients){
                client.getBasicRemote().sendText(message);
            }
        }
    }
}