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Java Java Objects (Retired) Delivering the MVP Defaulting Parameters

Code Challenge help

So at your new Java job, you've written a brand new Shopping Cart system for the website. After some developers have used the objects you created for a while, they ask you to make it easier to add things to the cart.

Check out more instructions in Example.java. Once you implement their request, check your work, and you will pass the challenge.

public class Example {

public static void main(String[] args) { ShoppingCart cart = new ShoppingCart(); Product pez = new Product("Cherry PEZ refill (12 pieces)"); cart.addItem(pez, 5); /* Since a quantity of 1 is such a common argument when adding a product to the cart, * your fellow developers have asked you to make the following code work, as well as keeping * the ability to add a product and a quantity. / Product dispenser = new Product("Yoda PEZ dispenser"); / Uncomment the line following this comment, after adding a new method using method signatures, to solve their request in ShoppingCart.java */ // cart.addItem(dispenser); }

}

public class ShoppingCart {

public void addItem(Product item, int quantity) { System.out.printf("Adding %d of %s to the cart.%n", quantity, item.getName()); /* Other code omitted for clarity. Please imagine lots and lots of code here. Don't repeat it. */ } }

public class Product { /* Other code omitted for clarity, but you could imagine it would store price, options like size and color */ private String mName;

public Product(String name) { mName = name; }

public String getName() { return mName; } }

2 Answers

Brendon Butler
Brendon Butler
4,254 Points

You're essentially asking us to do your work for you. If you really want to learn how to program, read the comments and try to solve the issue yourself or even go back, look at previous learnings and find your solution.

Basically all it is asking for you to do is to remove the comment '//' from one of the last lines in the Example class.

After doing that you'll want to add an "addItem()" method to the shopping cart class that only takes a Product variable. That should be enough information to get you started.

I feel that you, and anyone with this same road block should stop before heading to the community and break down the problem before asking for a handout. That's no way to learn.

Just for clarity, I also had this issue for the code challenge and got stuck on it for a little while. I had the code broken down like Brandon here said. I uncommented the code in the Example.java class, then I added another addItem() method to the ShoppingCart class that only took one perimeter, a Product. Then I simply printed out the string "Adding %s to the cart", item.getName()); This would have worked but it was issuing you an error. What the challenge wants is for you to recall the original addItem() method with the Product and pass in the value of 1 for the quality. So it should look like this:

addItem(item, 1); And that will pass.