[Saumyaraj]

I am aware of the essence of polymorphism i.e I can declare a reference variable of type superclass and assign it to a subclass object but why i am not able to declare a reference variable of type subclass and refer it to superclass object....plzzz help

package confusion;
class Sup
{    
    void print()
    {
    System.out.println("hello");
    }
}
public class Sub extends Sup
{
    public static void main(String[] args)
    {
  Sub ob= new Sup();
  ob.print();
    }
}