Accessing static nested class with object of enclosing class

[Cyril Sadasivan]

class Demo{
	static int a=10;
	static class Nested{
		static int b=20;
	}
}

class Test{
	public static void main(String... args){

		System.out.println(Demo.a);
		System.out.println(new Demo().a);

		System.out.println(Demo.Nested.b);
		//System.out.println(new Demo().Nested.b);
	}
}

The commented line of code doesn't compile.
I thought it should have because static members can be accessed through objects too.
Any justifications?

[Enkita mody]

I think you had forgotten correct syntax i.e new Demo.Nested().b;

[Cyril Sadasivan]

yeah that's right but the point is

if a static member variable can be accessed with object of enclosing class(objectOfEnclosingClass.staticVariable),
why can't static member class be accessed with object of enclosing class(objectOfEnclosingClass.staticNestedClass)?

[Enkita mody]

You shouldn't compare static class with static variables because it is really not.Static class is a Top level class, and Why can't you do that? because API doesn't allow that.We have to follow API.It won't work according to your desire.

[Henry Wong]

Cyril Sadasivan wrote:

		System.out.println(Demo.Nested.b);
		//System.out.println(new Demo().Nested.b);

The commented line of code doesn't compile.
I thought it should have because static members can be accessed through objects too.
Any justifications?

I guess it can be argued that if the first is allowed, then the second should be allowed too -- considering other cases where it is similarly allowed.

The answer to this is likely defined somewhere in the JLS, but quite frankly, I was never a fan of using an instance to get to any static component, so never looked it up.... hence, I am leaving it as an exercise to the OP...

Henry