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Java Java Objects (Retired) Delivering the MVP Defaulting Parameters

Shopping Cart: System.out does not show 1 Yoda Pez dispenser

I am doing the shopping cart Challenge Task and it is asking me to create a new method (using method signatures) that will take just the product as an argument and automatically set the quantity to one. I have no idea what could be wrong. It is saying that the test may be uncommented but it is. HELP!

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 item){
    System.out.printf("1 %s.\n", 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

Your new function should return the original function, but when you call the original function you use the value of 1 where you would put a quantity.

Ahhh I understand now! Thank you very much. Is this the common way to employ method signatures? (i.e. the 'new' method returning the 'old')

It is a common way. Whether you use it or not is very much dependent on the context of why and how you are writing the method with a different signature. In this case it makes sense not to repeat the code from the original function when you can just call it with one parameter already filled in.