need help in defaulting parameters Stage 4 -Delivering the MVP . Don,t know how to proceed.

Question

There is a function addItem (product item, quantity) which takes a product object and its quantity as parameters. To simplify adding a product to the cart when quantity is 1 , we have to make changes to the code.

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 this line after 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 */
  }
}

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;
  }
}

Answer 1 · 2015-04-23T16:02:05Z

April 23, 2015 4:02pm

Hi,

If you modify the addItem method to just take one parameter, then call the existing method inside the new one, setting quantity as 1.

Something like:

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 */
  }

  public void addItem(Product item) {   // <-- only one parameter here
    addItem(item, 1);   // <-- use the original method here
  }
}

I hope that makes sense!

And don't forget to uncomment the line in Example.java:

// cart.addItem(dispenser);

Uncomment that.

Steve.

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Ashwini Tiwari

Ashwini Tiwari

need help in defaulting parameters Stage 4 -Delivering the MVP . Don,t know how to proceed.

1 Answer

Steve Hunter

Steve Hunter

Ashwini Tiwari

Ashwini Tiwari