How to access inner class in an interface?

An inner class always behaves like a data variable of its encoding class or interface. By default all variables which are declared in an interface are final and static. A class defined inside an interface is implicitly static.

interface InterfaceXYZ {
  class InnerXYZ {
  }
}
class Program {
   public static void main(String[] args) {
       InterfaceXYZ.InnerXYZ  inner = new InterfaceXYZ.InnerXYZ();
   }
}