无状态会话Bean中的火灾事件无效

Question

我是WebSocket Java开发的新手，我有一个包含服务的会话bean：

@Stateless
@LocalBean
public class TransferService implements TransferServiceLocal {

@Inject
private Event<PushNotification> notificationEvent;

@PersistenceContext
private EntityManager em;

private PushNotification createNotification(Integer userId, String title,
        String message) {
    PushNotification pushNotification = new PushNotification();
    pushNotification.setUserId(userId);
    pushNotification.setTitle(title);
    pushNotification.setMessage(message);
    pushNotification.setDcr(new Date());
    // Notify the observers about the new push notification
    notificationEvent.fire(pushNotification);
    return pushNotification;
}

@Override
public void addTransfer(Transfer transfer) {
    em.persist(createNotification(visitor.getId(), "New Task", "You have new task"));
    em.persist(transfer);

}
}

我希望当我在EntityManager上创建一个新的persist时，会发送一个从websocket到客户端的新通知，问题是fire事件无法正常工作!!

以及我在WebSocket POJO中的内容：

import javax.enterprise.event.Observes;
import javax.websocket.server.ServerEndpoint;
import persistence.PushNotification;

@ServerEndpoint("/testws")
public class TestEndpoint {

private SessionRegistry sessionRegistry;

public void send(@Observes PushNotification notification) throws IOException{

    Set<Session> sessions = sessionRegistry.getAll();
    for (Session session : sessions) {
        session.getBasicRemote().sendText(toJson(notification));
    }

    System.out.println("new notification, message : "
            + notification.getMessage());
}

private String toJson(PushNotification notification) {
    final JsonObject jsonObject = Json.createObjectBuilder()
            .add("id", notification.getId())
            .add("message", notification.getMessage()).build();
    return jsonObject.toString();
}
}

我的代码出了什么问题请在最后两天遇到这个问题并且仍然困惑:(