Java EE 6: How to call Stateful Session Bean from Stateless Session Bean?

Question

I have a Stateful Session Bean (SFSB) which acts as authentication module. In the SFSB I store the current user that is logged in. Moreover I have some facades (which are Stateless Session Beans (SLSB)) that handles the JPA/SQL stuff for my entities. In order to check the access permissions of the current user, I try to call the SFSB out of the SLSB. But the current user field is always "null" when called from SLSB. When calling the SFSB directly, the current user field is set correctly... For calling I use the @EJB annotation.

Any ideas what the problem might be? Is that somehow a context problem? Is it generally possible to call a SFSB from SLSB preserving it's state?

Many thanks in advance!

Answer 1

You shouldn't call a stateful session bean from a stateless session bean.

Here is some reading: JEE6 Tutorial - Session Beans

Stateless beans don't know anything about your session. Any time you call it, it is stateless. Then it calls a stateful session bean. No surprise it doesn't have any context relating to the state of the client's session because it is called from stateless object.

I don't know if it will work, but you possibly could try to get the context by doing a JNDI lookup instead of DI using the @EJB notation. Something like this in the stateless ejb might work. You'll probably have to play with it and I can't guarantee anything. It should get the context of the client calling the stateless ejb. The client will need to have session context/scope or forget it.

@Resource SessionContext sessionContext;

MyStatefulBean msb = (MyStatefulBean)sessionContext.lookup("ejb/MyStatefulBean");
msb.doSomething(fubar);

It is better to call the stateful session bean from a client that has a session scope or from another stateful ejb. Stateless and stateful have different reasons for being.