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Java Java Objects (Retired) Delivering the MVP Defaulting Parameters

How do I create a method signature for this challenge

Hi there,

I am working on a challenge with multiple files, and I am supposed to uncomment a comment line on Example.java, then fill out a necessary request for ShoppingCart.java using method signatures. I have tried most methods and ideas I can think of, but I just cant quite get it. It's kind of a packed challenge, so if you could look at it yourself, that might be helpful. Any helpful ideas would would be appreciated. Thanks!

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());
    cart.addItem();
    /* 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

To rephrase the exercise, notice that ShoppingCart has an addItem() method with two parameters, a Product and a quantity. So cart.addItem(pez, 5) in class Example matches the current ShoppingCart addItem() method signature and will work (compile). But if you uncomment the line cart.addItem(dispenser) as requested, it should not currently compile because it doesn't match the method signature, meaning the method expects two parameters, but you provided only one (dispenser). So you are asked to modify the code in ShoppingCart to make the second method in Example work also. This involves adding an additional (overloaded) addItem() method to the ShoppingCart class that takes only a Product parameter. It should look very similar to the two parameter version, except that it defaults to a quantity of 1.