Java static class 内部 class

Question

Problem: Java allows static nested classes inside an outer class, and allows further static nested classes inside those static nested classes. It also allows non-static ("inner") classes nested inside an outer class. But for some reason I can't make a static class nested inside an inner class.

Why does the following code fail to compile?

class Outer
{
    // OK
    static class Static
    {
        // OK
        static class StaticDoubleNested
        {
        }
    }

    // OK
    class Inner
    {
        // BAD
        // "error: modifier static not allowed here"
        static class StaticDoubleNested
        {
        }
    }
}

Answer 1

As your inner class and outer class are calling the same (static) methode "static class StaticDoubleNested" coulde it be that the inner class methode is only Overriding the outer class methode?

If that`s the case then interfaces or abstract classes will be your choice.