Question

I have a multi-module project where the EJB BarService in project bar refers to a FooService EJB in foo project. The @EJB annotation is use to inject the EJB.

@EJB
private FooService fooService;

I’m using IntellijIDEA 11, and it complains with

‘Ambiguous EJB reference “beanName” or more precise “beanInterface” should be specified’.

This error is only showing up for EJB references in a different module. If I use the beanName as suggested, the error goes away. However I would prefer not to use it, since it would be hard to refactor the component name as it is a string.

Is this a bug in IDEA, or am I trying to do something wrong here?

(Noticed this and this asking the exact same question in the JetBrains forums, but there are no replies sadly).

Answer 1

The javadoc for javax.ejb.EJB is somewhat unclear on this point:

If no explicit linking information is provided and there is only one
session bean within the same application that exposes the matching
client view type, by default the EJB dependency resolves to that
session bean.

It’s debatable whether application in this context means “EJB module” or “EAR”, so I don’t necessarily think IDEA is to blame. I’m not familiar with other vendors, but at least WebSphere Application Server will attempt to disambiguate within the client EJB/WAR module before considering all EJBs in all modules in the EAR.