Why CurrentUser implements HasHandlers in gwtp-sample-tab?

Question

I am self learning GWT and GWTP. I am trying to set up my logging service and I want my currentUser object to be retrieved from the server before any Presenter that depends on it is revealed.

However, I have run into an issue which I think has to do with the fact that I don't understand why, on the gwtp-sample-tab example, the class CurrentUser implements HasHandlers!.

Can somebody explain it to me? Edit for a more precise question: what I would like to know is why, on the context of the sample, CurrentUser needs to implement HasHandlers. What functionality does that satisfy in the application?

Thanks a lot, Manu

PS. I am new to StackOverflow so if you think something is wrong with my question, please let me know.

When ever you are referring to something or some example add link to that, please. — Suresh Atta, Oct 02 '13 at 12:22

Suresh Atta · Accepted Answer · 2013-10-03T08:59:42.570

0

Because public class CurrentUser implements HasHandlers

because to implement the method

@Override
    public void fireEvent(GwtEvent<?> event) {
        eventBus.fireEvent(event);
    }

Which

Fires the given event to the handlers listening to the event's type.

So When a new User object creates this event register and fires at Gatekeeper(eventBus).

edited Oct 03 '13 at 08:59

answered Oct 02 '13 at 12:29

Suresh Atta

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I know what the interface does. What I do not understand is why, in the context of the sample, CurrentUser needs to implement that interface. It seems that it is not used anywhere since [AdminAreaPresenter](https://github.com/ArcBees/GWTP-Samples/tree/master/gwtp-samples/gwtp-sample-tab/src/main/java/com/gwtplatform/samples/tab/client/application/adminarea) uses a Gatekeeper and the [Gatekeeper](https://github.com/ArcBees/GWTP-Samples/blob/master/gwtp-samples/gwtp-sample-tab/src/main/java/com/gwtplatform/samples/tab/client/security/IsAdminGatekeeper.java) access the CurrentUser object directly – manubot Oct 02 '13 at 16:18
It makes sense. However I still don't see how GateKeeper listens to that particular event, there does not seem to be any handler registered for it. Is that due to some magic behind the curtains? – manubot Oct 03 '13 at 10:20
Haven't looked through full code, yes there must be something to recieve the event and handle it. – Suresh Atta Oct 03 '13 at 10:29
There is nothing on the sample code. Unless Gatekeeper has some magic to register handlers based on its attributes class name I think the event is not listened anywhere. Anyways thanks for the clarifications – manubot Oct 03 '13 at 21:35

Why CurrentUser implements HasHandlers in gwtp-sample-tab?

1 Answers1