Static Innerclass

[Chandana Garlapati]

 
 public class Outer extends Thread{

       public void run(){
              System.out.print("1");
       }

     static  class Inner extends Outer{
             public void run(){
                System.out.print("2");
             }
        }

        public static void main(String args[]){

               Outer ob1=new Outer();
               Outer ob2=new Outer.Inner();
               Inner ob3=new Outer.Inner();

               ob1.start();
               ob2.start();
               ob3.start();
        }
}  

If i run multilpe times this program shows the output 122,212 so on...
Whats going on here???

What is meant by these lines??

A static inner class can NOT be instantiated, through an instance of outer class.
and
Non static inner class cannot access, without having an instance of the outer class.

I have no idea about that??
can any one please explain???

[Dejan Miler]

First part.
In this code (above) we have two threads who are competing for execution time.
Read more about that here

Second part

class Outer {

    class InnerRegular {
    }

    static class InnerStatic {
    }
}

A static inner class can NOT be instantiated, through an instance of outer class.

Outer outer = new Outer();//create instance of the outerclass
Outer.InnerRegular staticInner = outer.new InnerStatic(); //ilegal
Outer.InnerStatic staticInner = new Outer.InnerStatic(); //legal

Non static inner class cannot access, without having an instance of the outer class.

//in oder to create instance for InnerRegular class we have to do the fallowing
Outer outer = new Outer();//create instance of the outerclass
Outer.InnerRegular innerRegular = outer.new InnerRegular();
//or
Outer.InnerRegular innerRegular2 = new Outer().new InnerRegular();

Dejan.

[Chandana Garlapati]

Thanks Dejan