How to fill @EJB annotated fields programmatically via glassfish container?

Question

I have a following problem. I have defined an interface:

@Local
public interface ProductTypeLister {
   Collection<ListElement> getList();
}

Also, I have defined an implementation for this thing:

@Stateless(name = "ProductTypeLister")
@Local(ProductTypeLister.class)
public class ProductTypeListerImpl implements ProductTypeLister {
   @Override
   public Collection<ListElement> getList() {
      // Implementation code
   }
}

And now I want to use it via annotation:

public class ListProductTypeAction extends ActionHandler {
   @EJB
   protected ProductTypeLister lister;

   @Override
   public String execute(HttpServletRequest request) throws ServletException {
      request.setAttribute("list", lister.getList());
      return "listPage.jsp";
   }
}

But I get the NullPointerException, since lister is not filled. Now, the problem is, that ActionHandler is not a derivative of HttpServlet and is not executed by the container itself. Instead, we are using FrontController patter - i.e. there is one servlet that handles all the incoming messages and creates required handlers via a simple construction. And therefore the EJB annotated fields are not filled automatically. However, I can fill this specific case in the following manner:

public ListProductTypeAction() throws NamingException {
  InitialContext context = new InitialContext();
  lister = (ProductTypeLister) context.lookup("<PATH>/ProductTypeLister");
}

In that case everything works fine, but this means I have to do for every handler the specified lookup with JNDI help, but all I want is to get it with annotation help. Therefore, the main servlet needs the following method:

private void fillHandler(ActionHandler handler) {
  // Fill @EJB annotated fields
}

But how can I fill it? Of course, I can manually run through every field and check if it's annotated EJB and fill it using JNDI based on the interface unqualified name. But is there a way to do this using the libraries I already have? After all, Glassfish is supposed to fill those fields during the deployment phase. How can I make him do that for a non-servlet class?

Answer 1

J2EE tutorial

Dependency injection is the simplest way of obtaining an enterprise bean reference. Clients that run within a Java EE server-managed environment, JavaServer Faces web applications, JAX-RS web services, other enterprise beans, or Java EE application clients, support dependency injection using the javax.ejb.EJB annotation.

Applications that run outside a Java EE server-managed environment, such as Java SE applications, must perform an explicit lookup. JNDI supports a global syntax for identifying Java EE components to simplify this explicit lookup.

So even if your class is inside a J2EE container, but its lifecycle is not managed by container, you are out of luck, you have to do it manually.