Java, hiding methods of super super class

Question

I am porting some OpenGL Nvidia C samples to jogl and I have the following (init is one of the abstract methods required by GLEventListener:

public abstract class NvAppBase implements GLEventListener {
    @Override
    public void init(GLAutoDrawable drawable) {
        initRendering(gl4);
    }
    public void initRendering(GL4 gl4) {
    }
}

public abstract class NvSampleApp extends NvAppBase {
    @Override
    public void init(GLAutoDrawable drawable) {
        baseInitRendering(gl4);
    }
    protected void baseInitRendering(GL4 gl4) {
        initRendering(gl4);
    }
    @Override
    public void initRendering(GL4 gl4) {
    }
}
public class BindlessApp extends NvSampleApp{    
    @Override
    public void initRendering(GL4 gl4) {    
    }
}

Given that:

NvAppBase is not used at all, all the samples (such as BindlessApp) always extend NvSampleApp
I'd like the class extending NvSampleApp to being able to see (and overwrite) only the initRendering and not also the init

Is there a better way than just having NvSampleApp simply as a variable inside BindlessApp, like this for example?

public class BindlessApp {    
    private NvSampleApp sampleApp;
}

1

Are you looking for `final`? – tkausl Jan 21 '16 at 08:05

score 3 · Accepted Answer · answered Jan 21 '16 at 08:06

3

You can use the keyword final for this purpose.

Writing Final Classes and Methods on Oracle java tutorial.

You can declare some or all of a class's methods final. You use the final keyword in a method declaration to indicate that the method cannot be overridden by subclasses. The Object class does this—a number of its methods are final.

answered Jan 21 '16 at 08:06

Ferrybig

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Yep, right, it works perfectly... thanks man, I can accept it in 3m – elect Jan 21 '16 at 08:10

score 1 · Answer 2 · edited May 23 '17 at 12:31

1

Is there a better way than just having NvSampleApp simply as a variable inside BindlessApp, like this for example?

Although it seems like more work, encapsulation is a great tool to help isolate parts of your code an decrease coupling.

I think in your case it might even be the better solution :)

See for more detail this answer: https://stackoverflow.com/a/18301036/461499

edited May 23 '17 at 12:31

Community

1
1

answered Jan 21 '16 at 08:09

Rob Audenaerde

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I'd like to go with the Ferrybig's answer, but thanks anyway for the interesting link – elect Jan 21 '16 at 08:12

Java, hiding methods of super super class

2 Answers2