Abstract inner class?

[Aiping Zhou]

Can a non-abstract class have an abstract inner class? Like this:

  
class A{
   abstract class B{}
   interface I{} //100% abstract class
   class C extends B implements I{}
}

Can anybody clear this for me?
Thanks.

[shweta mathur]

Yeah, it can.. I don't think there will be any problem in your class. Inner classes are just helper classes to the main class. You can define an abstract class and then extend it.
See the following example. I just extended your class to do something and it works fine.

 
class A{
abstract class B{
void m1(){System.out.println("In B.m1");}
}
interface I{
void m2();
} //100% abstract class
class C extends B implements I{
//void m1(){System.out.println("In m1");}
public void m2(){System.out.println("In m2");}
void m3(){System.out.println("In m3");}
}
void Amethod(){
C c = new C();
c.m1();
c.m2();
c.m3();
 }
}
public class InnerAbstract{
public static void main(String[] args){
A a = new A();
a.Amethod();
}
}

o/p
In B.m1
In m2
In m3