public static void main(String[] args){
      Light lamp = new Light();
      Command switchUp = new FlipUpCommand(lamp);
      Command switchDown = new FlipDownCommand(lamp);
 
      Switch s = new Switch();
 
      try {
         if (args[0].equalsIgnoreCase("ON")) {
            s.storeAndExecute(switchUp);
         }
         else if (args[0].equalsIgnoreCase("OFF")) {
            s.storeAndExecute(switchDown);
         }
         else {
            System.out.println("Argument \"ON\" or \"OFF\" is required.");
         }
      } catch (Exception e) {
         System.out.println("Arguments required.");
      }
   }