Playing Compiler—Upcasting and DowncastingExplain why the following classes do not compile...

Playing Compiler—Upcasting and Downcasting

Explain why the following classes do not compile.

   public class Papa   {     protected int x;     public Papa()     {       x = 0;     }     public Papa(int y)     {       x = y;     }   }

   public class Daughter extends Papa   {     public Daughter()     { }     public static void main(String[] args)     {       Daughter d = new Papa(2);     }   }