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javainterfacenestedimplements

What happens when implementing Parent interface that declares a Nested Interface

I searched Google but couldn't find a specific example that clears my doubt. Suppose I have a parent interface with nested interface.

E.g 

public interface A {
    .. methods

    interface B {
        .. methods
    }
}

If a class implements interface A, what happens, does that class internally implements the nested interface B as well, that means am I supposed to override interface B's methods too?

Solution

  • No. The inner interface has to be implemented.

    Syntax would be

    Class C implements A, A.B{
// add methods here
}

    If you implement only A, you are fine with only declaring A's method without B interface methods.