Abstract classes and interface

Question

In the default interface, a data item is static and final. Statically, this is because it cannot be created, but why is it final?

and another question - even abstract classes cannot be created, why can it have a non-static data member?

Answer 1

and the other question is even the abstract classes can not be instantiated,
then why it can have a non static data member??

Because in abstract classes, you can define as many functions that you want, which can then be used by its children.

Answer 2

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