Deadlock in unit test initializing static member

[olpf]

Hi,

I am quite new with CDI. In my junit test with CDI-unit I added a cache as static member in a dao like this:

private static Map<CacheKey, Map<String, String>> CACHE = new HashMap<>();

This leads to a deadlock when I execute the test.

If I init the cache like this:

@PostConstruct

          public void afterInjection()

          {

                         CACHE = new HashMap<>();

  }

There is no deadlock. I am using weld 2.0.2.Final in the test.

Does anyone know the reason?

Cheers

Oliver

[mkouba]

Hi Oliver,

could you describe your test and dead lock symptoms more thoroughly? E.g. what is the scope of the bean with the static member? BTW I don't think it's a good idea to place a static member on a bean class. Also it's not synchronized so that it's not thread-safe...

[olpf]

Hi Martin,

Symptoms are that the junit test run hangs and newer exits. Unfortunately the information in the debugger when I suspend the thread are not useful for me. The class which is injected has no specific scope assigned. So probably it is the default scope? If I climb up the object tree a parent has @ApplicationScoped and that parent @EJB.

I thought about to do it with @Singleton instead of the static members. But I synchronized the access/change of the cache with synchronized blocks...so I think it is thread safe. But the initialization of the static member takes place on class loading, I do not know but I am wondering if this seems to be a problem with weld.

The cache is located inside a DAO, the DAO is accessed by a service and the service is injected in a junt 4 test.

[mkouba]

Hm, that's weird. I'll try to dig deeper. Anyway @javax.ejb.EJB and @javax.ejb.Singleton are not CDI scopes. @javax.ejb.EJB is used to inject EJBs. @javax.ejb.Singleton denotes a singleton session bean.

[olpf]

Ok. Thank you. I realized the cache now as @Singleton annotated class instead of a static member. I know that annotation mention are no scopes. But I think the annotation singleton is more sexy than static members