The InnerThis program illustrates the use of this in inner classes. It creates an instance of the InnerThis class, which creates an instance of the Inner class.
The Inner class is an inner class of InnerThis. The this.i expression refers to the i variable of Inner. The InnerThis.this.i expression refers to the i variable of InnerThis. The output of the program is:

2
1

class InnerThis {
	int i = 1; 
	public static void main(String[] args) 
	{
		new InnerThis(); 
	}
  InnerThis() {
		new Inner(); 
	}
	class Inner {
		int i = 2;
		Inner() {
			System.out.println(this.i);     
			System.out.println(InnerThis.this.i);  
		}
	}  
}