private void setImage(int roll, JLabel die)
   {
      switch (roll)
      {
         case 1: die.setIcon(one);
                 break;
         case 2: die.setIcon(two);
                 break;
         case 3: die.setIcon(three);
                 break;
         case 4: die.setIcon(four);
                 break;
         case 5: die.setIcon(five);
                 break;
         case 6: die.setIcon(six);
                 break;                    
       }
    }