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Java Java Objects (Retired) Delivering the MVP Defaulting Parameters

Shopping Cart exercise not working

I added the new method signature to ShoppingCart.java by overloading the method and then went to Example.java and uncommented the line allowing the new dispenser to be added to the cart. But I'm still not passing the exercise because the system is saying I didn't uncomment the line.

Example.java
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 this line after using method signatures to solve their request in ShoppingCart.java
    cart.addItem(dispenser);
  }

}
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 */
  }

  public void addItem(Product item) {
    System.out.printf("Adding one %s to the cart.%n", item.getName());
    /* Other code omitted for clarity */
  }
}
Product.java
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;
  }
}

In the original code, the line is as follows:

//cart.addItem(dispenser);

I uncommented that one and it's still not working.

2 Answers

Dan Johnson
Dan Johnson
40,533 Points

It's looking for a more terse method overload. In order to avoid code duplication you can write it like this:

public void addItem(Product item) {
    addItem(item, 1);
}

The code you posted in your question will work.

All you need to do is change

"Adding one %s to the cart.%n"

to

"Adding 1 of %s to the cart.%n"