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Java Java Objects (Retired) Delivering the MVP Defaulting Parameters

Abe Daniels
Abe Daniels
Courses Plus Student 2,781 Points

Should I re-evaluate my knowledge of java?

This seems like a big task. I feel like the past few exercises have been less of me using my knowledge than getting help from other people. I don't feel like I'm going to be learning anything if I'm not fully understanding the code I'm using. Sure it makes sense when I see someone write out how it's supposed to be written and can use context clues to understand what the code is doing, but I feel like that isn't an effective way for me to learn. Now I am thinking, should I go back to the beginning and review everything I've already had presented to me? Thanks.

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

Brennen Kulikowski
Brennen Kulikowski
2,428 Points

For this program, you already have a function addItem which has parameters for a Product and an int. Find a way to use this function with a quantity of 1. Note that addItem has a lot of code, so you can't repeat it.

Aaron Arkie
Aaron Arkie
5,345 Points

It's always good to review your basics! I do it all the time. Its always better to start off on a strong foundation than a weak one else your kingdom shall crumble. It's not so much that it is a big task it just requires you to really look at the problem. Think about the problems in these terms, what do i know? What do i need? What past experiences can i bring into this problem that may help me find a solution? I noticed this question is almost a month old. Do you still need some guidance?