What is wrong with line 1?
public class G
{
   private int x;
   public G() { x=3;}
   public void setX(int val){
      x=val;
   }
   public String toString(){
      return ""+x;
   }
}
public class H extends G
{
   private int y;
   public H() { y=4;}
   public void setY(int val){
      y=val;
   }
   public String toString() {
      return ""+y+super.toString();
   }
}
//test code in the main method
G bad = new H();
bad.setY(9);      //line 1