public void printVegetarianMenu() {
    System.out.println("Vegetarian");
    Iterator pancakeIterator = pancakeHouseMenu.createIterator();
    Iterator dinerIterator = dinerMenu.createIterator();

    while (pancakeIterator.hasNext()) {
      MenuItem menuItem = (MenuItem) pancakeIterator.next();
      if (menuItem.isVegetarian()) menuItem.print();
    }
    while (dinerIterator.hasNext()) {
      MenuItem menuItem = (MenuItem) dinerIterator.next();
      if (menuItem.isVegetarian()) menuItem.print();
    }
  }
 public void printMenu(Iterator iterator) {
   while (iterator.hasNext()) {
     MenuItem menuItem = (MenuItem) iterator.next(); // object down casting to MenuItem
     menuItem.print();
   }
 }