Raw Type warning extending a Generic Class

Question

I'm confused by the scenario described below where I am extending a generic class. The class I am extending is below:

public abstract class PresenterWidget<V extends View> extends HandlerContainerImpl
...

At first, I had this working (warning free) using the child class below:

public abstract class SideBarPresenter<V extends SideBarPresenter.MyView> extends PresenterWidget<SideBarPresenter.MyView> {

    interface MyView extends View {
        void doSomething();
    }
...

But I want to convert MyView to an abstract class so I can implement a method. The way I think it makes sense is below.

public abstract class SideBarPresenter<V extends SideBarPresenter.MyView> extends PresenterWidget<SideBarPresenter.MyView> {

    abstract class MyView implements View {
        void doSomething() {}
    }
...

The problem is this produces 2 warnings, both stating:

SideBarPresenter.MyView is a raw type. References to generic type SideBarPresenter.MyView should be parameterized

Should I just ignore this warning or is there a better way to do this?

Never, **ever**, ignore any warnings. They are there for a good reason. For raw types, refer to this question: http://stackoverflow.com/questions/2770321/what-is-a-raw-type-and-why-shouldnt-we-use-it — Tunaki, Mar 05 '16 at 21:54
@Tunaki thanks for the reply, I have actually worked with raw types quite a bit but I am struggling with this specific scenario. I agree though on never ignoring warnings, that's why I am posting this question :) — The Gilbert Arenas Dagger, Mar 05 '16 at 22:06
View **is** a class ([Ref](https://docs.oracle.com/javase/7/docs/api/javax/swing/text/View.html)) — 4castle, Mar 05 '16 at 22:07
Let us [continue this discussion in chat](http://chat.stackoverflow.com/rooms/105462/discussion-between-the-gilbert-arenas-dagger-and-4castle). — The Gilbert Arenas Dagger, Mar 05 '16 at 22:10

score 4 · Accepted Answer · answered Mar 05 '16 at 22:13

4

You should make MyView a static class. Otherwise its actually an inner class of a SideBarPresenter instance and that's probably where your generics warning is coming in. Inner interfaces are static by default.

answered Mar 05 '16 at 22:13

sisyphus

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Raw Type warning extending a Generic Class

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