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Java Java Objects (Retired) Delivering the MVP Defaulting Parameters

Heavy Quiz don't know where to start.. (maybe missunderstood)

This is really heavy and I don't know where to start

If I understood the first quiz my mission is to uncomment the cart.addItem(dispenser); and then add numbers like this cart.addItem(dispenser,12);

The compilator didn't complain but quiz does..

"Bummer! Loos like you did not add a new method signature for addItem to ShoppingCart. It should just take one parameter of (Product item)"

Huh? Nada.

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

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;

3 Answers

Hi there,

To save me a load of typing, and you having to wait for that ... have a look at this post that covers this challenge in some detail.

Let me know how you get on. :+1:


Keli'i Martin
Keli'i Martin
8,227 Points

So it looks like the quiz wants you to overload the addItem() function. In other words, you need to create a new method signature in ShoppingCart.java that only takes the Product as a parameter.

public void addItem(Product item) {
    // you also need to add something inside this function

Above I've shown what the method signature should be, but I left the body of the function empty. You will need to add something in there to accomplish the task. Hint: How would you add just 1 of the items using the original addItem() method?

Hope this helps you get back on track!

thanks I got passed but must say that quiz was really hard to understand.. I need like more quiz/practise.. Can anyone suggest me?

That is a tough one, yes. If you carry on with the Java courses, and keep asking questions in here when you get stuck, you'll pick it up in no time. You just need to keep practicing. We all do!