Unsatisfied dependencies for type [...] with qualifiers [@Default] at injection point (using @Stateful EJB with CDI)

Question

I have the following code to manage two kinds of repositories. Both repository classes inherit an interface to allow reinitialization of their resources.

public interface CachingRepository
{
    public void invalidateCache();
}

Global, application-scoped repo:

@Named("globalRepo")
@ApplicationScoped
public class GlobalRepository implements CachingRepository
{
    private List<Category> categories;

    ...

    @Override
    public void invalidateCache()
    {
        categories = null;
    }

    ...
}

Per user, session-scoped repo:

@Named("userRepo")
@SessionScoped
//@Stateful         // <- NOTE HERE
public class UserRepository implements CachingRepository, Serializable
{
    private List<MyFile> files;

    @Override
    public void invalidateCache()
    {
        files = null;
    }

    ...
}

When injecting this (without @Stateful) into the context

@Named
@ViewScoped
public class MyHandler implements Serializable
{
    @Inject
    private UserRepository userRepo;

    ...
}

it works. However, when adding @Stateful to the UserRepository class, deployment fails with an exception saying:

Caused by: org.jboss.weld.exceptions.DeploymentException: WELD-001408 Unsatisfied dependencies for type [UserRepository] with qualifiers [@Default] at injection point [[field] @Inject private de.company.project.pack.MyHandler.userRepo]
    at org.jboss.weld.bootstrap.Validator.validateInjectionPoint(Validator.java:275)
    at org.jboss.weld.bootstrap.Validator.validateInjectionPoint(Validator.java:244)
    at org.jboss.weld.bootstrap.Validator.validateBean(Validator.java:107)
    at org.jboss.weld.bootstrap.Validator.validateRIBean(Validator.java:127)
    at org.jboss.weld.bootstrap.Validator.validateBeans(Validator.java:346)
    at org.jboss.weld.bootstrap.Validator.validateDeployment(Validator.java:331)
    at org.jboss.weld.bootstrap.WeldBootstrap.validateBeans(WeldBootstrap.java:366)
    at org.jboss.as.weld.WeldContainer.start(WeldContainer.java:83)
    at org.jboss.as.weld.services.WeldService.start(WeldService.java:76)
    ... 5 more

Adding the name of the CDI bean like

@Inject @Named("userRepo")
private UserRepository userRepo;

results in the same exception. The only thing that works in conjunction with @Stateful is to use the interface in the var declaration:

@Inject @Named("userRepo")
private CachingRepository userRepo;

I might need sub class functionality here however, so using CachingRepository isn't really desired (at the moment).

Q's:

1. Why isn't this working as expected? The UserRepository var should already identify which class to instantiate, shouldn't it? What's the logic to this?
2. Why does the @Stateful EJB annotation have such severe effects here? Why does it essentially force me into using the CachingRepository interface in the var declaration?

---

Note, I' using Seam 3 Faces making the @ViewScoped become a CDI view-scoped bean, so the problem at hand is likely still CDI-only.

Answer 1

I had the same problem with this misleading exception...

By adding @Stateful to UserRepository you expose EJB methods of the CachingRepository interface without having a no-interface view declared. Add @LocalBean to UserRepository to activate the no-interface view. See EJB 3.1 Specification, Section 4.9.8 "Session Bean's No-Interface View"

The bean class must designate that it exposes a no-interface view via its bean class definition or in the deployment descriptor. The following rules apply:

• ...
• If the bean exposes at least one other client view, the bean designates that it exposes a no-interface view by means of the @LocalBean annotation on the bean class or in the deployment descriptor.
• ...

I also refer to this stackoverflow answer for more information about no-interface views.