Non-static nested classes are called inner classes. Nested classes that are declared static are called static nested classes. A nested class is a member of its enclosing class. Non-static nested classes (inner classes) have access to other members of the enclosing class, even if they are declared private.
Read moreCan inner class extend any class?
It can extend exactly one class or implement exactly one interface . It can implement multiple interfaces regardless of whether it also extends a class.
Read more