Jboss Service / Managed Bean Question

Question

I have a managed bean / service running inside of JBOSS. I then have a quartz job that will occasionally wake up and call a method of the managed bean. This method is sometimes long and drawn out, and since I don't want the quartz job to time out, I have implemented a thread within the managed bean to perform the processing. When the thread is finished I need to update a database table with the results. This is a very serial process and it needs to be based upon some business rules, etc.

My main question is that I can use an EntityManager within the service without a problem however I can not use it from within the thread, I get a NullPointerException. What would be the best way to address this?

Thanks,

Scott

Answer 1

As creating threads in appservers is discouraged, I'd modify the setup a bit.

I'd move the core of processing to a message driven bean, and have the Quartz job just send a message to the queue on which the MDB is listening. The MDB in turn can call your EJB, and like this everything remains within what's allowed by the standard.

Answer 2

As per the documentation and specification the Entity Manager is not thread safe and can not be used across different child threads as I had originally had in mind. I ended up going back to the original design similar to the one provided by fvu, however I found some annotations that would allow me to modify the been timeout period and allow the long running process to work properly. Here's the annotation that I used:

@PoolClass(value=org.jboss.ejb3.StrictMaxPool.class, timeout=360000000L)