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Thread: how to extend a subclass?!

  1. #1
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    Default how to extend a subclass?!

    hi,
    i want to write a class that extends from a subclass of another class,something like this:

    public class A{
    //some codes here
    public class B{
    //some codes here
    }
    }

    public class C extends A.B ( or public class C extends B ){
    //some codes here
    }

    can anyone help me with that?!
    Last edited by migongotar; August 2nd, 2011 at 11:48 AM.


  2. #2
    Crazy Cat Lady KevinWorkman's Avatar
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    Default Re: how to extend a subclass?!

    What happened when you tried? Did you get an error message?
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  3. #3
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    Default Re: how to extend a subclass?!

    when i try this code (public class C extends A.B) i get this error message :
    No enclosing instance of type DataStructures is available due to some
    intermediate constructor invocation

    i dont know how to resolve this error message...
    Last edited by migongotar; August 2nd, 2011 at 12:23 PM.

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    Default Re: how to extend a subclass?!

    That's because your B class is not a subclass, it's an inner class. And since your B class is not static, it belongs to a specific instance of A. So when you try to make C extend B, the compiler says "I can't reach B without an instance of A".

    Is there a reason you're keeping B as an inner class? Is there a reason it's not static?
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  5. The Following User Says Thank You to KevinWorkman For This Useful Post:

    migongotar (August 2nd, 2011)

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    Default Re: how to extend a subclass?!

    in fact, there's no reason! i just had no idea that static class would solve my problem and i forgot to try it! thanks anyway!

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