public void touch(int i)
   {
       if( Inventory.checkInventory(dairy.get(i).getName()) > 0)
       {
           System.out.println(dairy.get(i).getName()+" is added to your cart.");
           System.out.println(Inventory.checkInventory(dairy.get(i).getName())+ " items are left in stock");
           notifyObservers(dairy.get(i));
        }
        else
        {
            System.out.println(" Sorry!! " + dairy.get(i).getName()+ " can't be added to your cart. They are out of stock!");
        }
    }