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Java Java Objects (Retired) Delivering the MVP Defaulting Parameters

kaushlender kumar
kaushlender kumar
1,275 Points

Check out more instructions in Example.java. Once you implement their request, check your work, and you will pass the ch

Check out more instructions in Example.java. Once you implement their request, check your work, and you will pass the challenge.

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 */
  }

  public void addItem(Product item)
  {
    System.out.printf("");
  }
}
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;
  }
}

2 Answers

Rob Bridges
seal-mask
.a{fill-rule:evenodd;}techdegree seal-36
Rob Bridges
Full Stack JavaScript Techdegree Graduate 35,467 Points

Hello, what this code is doing is asking you to make another method if they just want to add one item, you did that correctly, however the method only prints a blank line when called. Try this.

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

This ensures that if the method is called with just the name of the item it will default to adding one quanity.

Let me know if this helps.

Here's how I understand the code challenge.

Example.java has a line of code that is commented out

    cart.addItem(dispenser);

If all you do is uncomment this line and check your work, you get a compiler error. We need to write a second addItem method that only takes one argument, rather than two.

So, in ShoppingCart.java, we can copy and paste the existing addItem method, but remove the second argument. We also need to change what is printed, because we know that we are "Adding 1 of" of the item to the cart.