public class EmptyFW extends FunListFW {

   private static EmptyFW _instance = new EmptyFW ();

   private EmptyFW () {
   }

   public static EmptyFW Singleton () {
      return _instance;
   }
   
  public Integer car() {
    throw new java.util.NoSuchElementException ("Empty has no element.");
  }

  public FunListFW cdr() {
    throw new java.util.NoSuchElementException ("Empty has no tail.");
  }

  public Object execute (IFunAlgo algo, Object input) {
      return algo.forEmpty (this, input);
   }
}