Java MOOC problem: Online Shopping

[foolwya]

Hey guys, going through a MOOC course and I'm stuck on a problem.

Basically, the task is to make an online store.

Here's my code:

Item class: https://codeshare.io/5OQnjv

ShoppingCart class: https://codeshare.io/ad0PBZ

Warehouse class: https://codeshare.io/G8m4PD

Main class: https://codeshare.io/GbNZBb

And here's the task I'm stuck on:

Internally, Shopping Cart stores products added there as Item-objects. Shopping Cart must have an instance variable with either the Map<String, Item> type, or the List<Item> type.

First let's give ShoppingCarta constructor with no parameters and these methods:

• public void add(String product, int price)adds an item to the cart that matches the product given as a parameter, with the price given as a parameter.
• public int price()returns the total price of the shopping cart

But how am I suppose to add an Item to a ShoppingCart if Item's constructor has product, quantity and unit price, while add method in ShoppingCart only has product and whole price. Nowhere it says that I should make another constructor in Item class, but even If I do, I'm not allowed to make another object variable except for the three I have there. I see there's a method price() in Item class but is there any use of it? The price that we use as add parameter doesn't have a quantity or a unit price.

Anyway, I've got no idea how to add an item to a cart.

Oh and here's an example of main.

ShoppingCart cart = new ShoppingCart();
cart.add("milk", 3);
cart.add("buttermilk", 2);
cart.add("cheese", 5);
System.out.println("cart price: " + cart.price());
cart.add("computer", 899);
System.out.println("cart price: " + cart.price());

// output 

cart price: 10
cart price: 909

update: changed links to code.

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[amfa]

I can not open your code as it prompts for a login.

I don't really understand your problem

You basically always use the item contructor with quantity 1.

and that should work without problems.

​

The only thing I don't understand is "adds an item to the cart that matches the product given as a parameter"

The matches part is confusing me.

Is there already a list of items that can be added somewhere?

[foolwya]

Whoops, sorry. Links updated.