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Java Java Objects (Retired) Delivering the MVP Defaulting Parameters

Pierre-Alexandre GROSS
Pierre-Alexandre GROSS
2,832 Points

Need help solving this challenge

I've been stuck on this problem for some days now and I've finished the rest of the module. I have a hard time understanding exactly what is expected in this exercise, but here is how I tried to solve it. I declared a member variable in the ShoppingCart class, to which I then assigned the value passed in the addItem method coming from the Example class and I wrote an if statement to set the quantity to 1 if it was < 1 to make 1 a default value. I keep getting the message that I didn't add a method signature, and I don't understand what's wrong.

Thanks for the help. Pierre.

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 {
  private int mQuantity;

  public void addItem(Product item, int quantity) {
    mQuantity = quantity;
    if (quantity < 1) {
      quantity = 1;
    }
    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. 
    */
  }
}
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

deckey
deckey
14,630 Points

Hi Pierre, as challenge is saying, you need a new method for adding default values of pez, by using the addItem() method that already exists.

To avoid revealing too much

  1. this new method will have the same name
  2. will take only one argument (dispenser)
  3. will call original 'addItem()' method, but will fill the integer value

hope it helps, good luck, Deckey