use of Outer.this

[Rick Reumann]

This was a qustion on a mock quiz:
How is an instance of Outer accessed from within an instance of inner within non static classes?
The answer was:
Outer.this
Can someone write some short code depicting this? I have been trying and can't seem to do it. Thanks so much.
Rick

[Rick Reumann]

Ok, I found the answer in Khalid & Mughal's book. Weird, I would have never thought to use 'this' like that since I've always just seen inner classes refer to the outer class members directly.

public class TestOuter {
    private int a = 5;
    
    public static void main( String[] args ) {
       TestOuter t = new TestOuter();
       t.doStuff();           
    }
    
    void doStuff() {
        Inner inner = new Inner();
        inner.doYourThing();
    }
    
    class Inner {
        void doYourThing() {
            System.out.println(" a = "+ a );
            //or
            System.out.println(" a = "+ TestOuter.this.a );
        }
    }        
}

What threw me off was the phrasing of the question and I'm still not sure it was phrased correctly. I was thinking of somehow getting a handle to an instance variable of the outer class with OuterClassName.this but in the above that's not really what I'm doing.

[Rob Ross]

Here ya go...

public class Outer
{
    int i = 5; //outer class's copies
    String name = "I am outer";
    
    //Inner class
    public class Inner
    {
int i = 10; //inner class's copies
String name = "I am inner";

//constructor
Inner()
{
    System.out.println("Printing inner i: "+i);  
    System.out.println("Printing inner name: "+name); 
    System.out.println("Printing outer i: "+Outer.this.i);
    System.out.println("Printing outer name: "+Outer.this.name);
}
    }//end  public class Inner
    
    /**
     *
     */
    static public void main(String[] args) 
    {
Outer.Inner myInner = new Outer().new Inner();
    }
}//end public class Outer

Rob