Question

I have a simple Store class that contains an Inventory object and a CashRegister object. In order to sell an item, the CashRegister object needs to access the Inventory object’s methods; namely, those which return a particular item’s price, quantity held in storage, etc. What’s the best way to give the CashRegister object access to the Inventory object’s methods?

Thank you.

Answer 1

the CashRegister object needs to access the Inventory object’s methods

Why? The CashRegister can exist and operate perfectly without an Inventory. You can have a CashRegister in a theater or a cinema, not only in a Store. This part of the logic you’re talking about should be part of the store.

class Store
{
   CashRegister register;
   Inventory I;
   void sellSomething(Item i)
   {
      //move logic inside the store
      //not in CashRegister
      int price = I.getPrice(i);
      register.addCash(price);
      I.removeItem(i);
   }
};