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Java Java Objects (Retired) Delivering the MVP Defaulting Parameters

Mark Miller
Mark Miller
45,831 Points

I've added the method signature that works when no quantity is ordered, and it appears in the preview as it should.

Why does the computer say that the 1 Yoda PEZ dispenser is not in the output, when it is appearing in the preview? I understand the challenge, and I believe I have the right answer. The code is not commented in Example.java.

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 the line following this comment,
       after adding a new method 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. Please imagine
       lots and lots of code here. Don't repeat it. 
    */
  }
  public void addItem(Product single_item) {
    System.out.printf("Adding one %s to the cart.", single_item.getName());
  }
}
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;
  }
}

1 Answer

Rob Bridges
seal-mask
.a{fill-rule:evenodd;}techdegree seal-36
Rob Bridges
Full Stack JavaScript Techdegree Graduate 35,467 Points

Hey There Mark,

You're repeating yourself by re-writing a method that you already had created, which this challenge was trying to prevent.

Try something like this below, so that you're calling the method that you've already written.

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 void addItem(Product single_item) {
    addItem(single_item, 1);
  }
}