Java - static Inner class

class Outer{
 private int x = 100;
 private static int y = 200;
 public Outer(){}
 public void disp(){
  System.out.println("x="+x);
  System.out.println("y="+y);
 }
 static class Inner{
  //private int a = 10;
  private static int b = 20;
  public Inner(){}
  public void setb(int x)
  {
   b = x;
  }
  public void disp_in(){
   //System.out.println("a="+a);
   System.out.println("b="+b);
   //System.out.println("x="+x);
   //System.out.println("y="+y);
  }
 }
}

public class Sic{
 public static void main(String[] arg){
  Outer.Inner oi = new Outer.Inner();
  oi.setb(40);
  oi.disp_in();
 }
}