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Java Java Objects (Retired) Delivering the MVP Defaulting Parameters

Ernest Lin
Ernest Lin
2,691 Points

I don't get what I am supposed to do here

What am I supposed to do here? I don't get the instructions at all

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. 
    */
  }
}
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

Chris Adamson
Chris Adamson
132,143 Points

Here they are looking for a 'convenience' method:

Tweak the shopping cart, to add one method:

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

It simply invokes the existing method to add one method.

Then in Example.java, uncomment the one line to actually use it:

    cart.addItem(dispenser);
Ernest Lin
Ernest Lin
2,691 Points

When I enter those in it still says ./ShoppingCart.java:4: error: method addItem in class ShoppingCart cannot be applied to given types; addItem(item, 1); ^ required: Product found: Product,int reason: actual and formal argument lists differ in length ./Example.java:6: error: method addItem in class ShoppingCart cannot be applied to given types; cart.addItem(pez, 5); ^ required: Product found: Product,int reason: actual and formal argument lists differ in length 2 errors