Two timeouts for one bean (order and design)

[piotrekde]

Hi,

My @Service bean must perform some action every 30 seconds and every 2 minutes. To achieve it, I'd like to use standard EJB Timer Service API.

The first thing is, that as far as I know, one bean cannot register itself for receiving more than 2 timeouts? I mean, that it can be only one ejbTimeout(Timer) method in case of implementing TimedObject interface, or only one method annotated with @Timeout, right?

So I've decided to design it using observer-like pattern:

Timeout A - every 30 seconds, Timeout B - every 2 minutes

// observer - like
@Service
public class MyServiceBean {
  public void onTimeoutA(Timer t) {
    // do some stuff
  }
  public void onTimeoutB(Timer t) {
    // do some stuff.
  }
}

@Stateless
public class TriggerA {
  @EJB
  MyService service;

  //(...)

  @Timeout // registered for timeout A
  public void timeoutA(Timer timer) {
    service.onTimeoutA(timer)
  }  
}

@Stateless
public class TriggerB {
  @EJB
  MyService service;

  //(...)

  @Timeout // registered for timeout B
  public void timeoutB(Timer timer) {
    service.onTimeoutB(timer)
  }  
}

Is it any more elegant way to do so?

The second question is about order of timeouts. It is easy to notice that every 2 minutes both timeout A and timeout B will be triggered. I'd like to make sure that in this case, timeout A will be fired _before_ timeout B:

(30sec): timeoutA, (60sec): timeoutA, (90sec): timeoutA, (120sec): timeoutA, timeoutB

How can I do it? (I use EJB 3.0 and JBoss)

Thanks in advance, any help appreciated

Piotr