SessionScoped cdi observer with @Inject for producer bean

Question

This is my current scenario:

@WebListener
public class WebListenerService implements HttpSessionListener{
 .... implement methods

 @Produces
 @Dependent
 public SessionDependentService sessionDependentService(){
 }

}

@SessionScoped
@Named
public class AccountController implements Serializable{

  //Injected properly and works as expected
  @Inject
  private SessionDependnetService sessionDependentService;
  @Inject
  @OnLogin
  private Event<Account> accountEvent;

  public void onLogin(){
    accountEvent.fire(authenticatedAccount);
  }
}

@SessionScoped
public class AccountObserver implements Serializable{

  //This does not work. It is always null.
  @Inject
  private SessionDependnetService sessionDependentService;

  public void onLoginEvent(@Observes @OnLogin final Account account) {
    //When this methods is invoked
    //the sessiondependentservice is always null here.
  }
}

In the AccountController, the SessionDependentService is correctly injected and is not null, while in the AccountObserver, it is always null.

EDIT: Event using the parameter injection still results to a null value.

 public void onLoginEvent(@Observes @OnLogin final Account account, final SessionDependnetService sessionDependentService) {
     //When this methods is invoked
     //the sessiondependentservice is always null here.
  }

Netbeans correctly highlights this as an injection point.

Why is this the case?

I am using wildfly 8 server.

maress maress · Accepted Answer · 2014-09-15T23:24:40

I changed the producer bean from SessionScoped to Stateless bean:

@Stateless
public class WebListenerSessionService {

 //Use Instance since http session are dynamic.
 @Inject
 private Instance<HttpSession> httpSession;

 @Produces
 @Dependent
 public SessionDependentService sessionDependentService(){
   //use session to lookup existing service or produce a new one.
 }

}

Even though this works fine, there is no where in the CDI spec which says Producer method must be session beans.

to quote:

A producer method must be a default-access, public, protected or private, non-abstract method of a managed bean class or session bean class. A producer method may be either static or non- static. If the bean is a session bean, the producer method must be either a business method of the EJB or a static method of the bean class.

And since @SessionScoped is a managed bean class, why would it an injection into an observer bean not work.

SessionScoped cdi observer with @Inject for producer bean

1 Answers