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Java Java Objects (Retired) Delivering the MVP Defaulting Parameters

Small problem with output.

I tried to have the code output that I am Adding 1 Yoda PEZ dispenser to the cart. When I check preview it says that my output is exactly that but I keep getting the error message.

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);

    Product dispenser = new Product("Yoda PEZ dispenser");


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("Adding 1 %s to the cart.%n", item.getName());
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

Grigorij Schleifer
Grigorij Schleifer
10,365 Points

Hi David,

you have to override the first addItem method that takes a single argument "item". Inside that "second" method call the "first" addItem method and pass it the item and the quantity 1.

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

Makes sense?


Thanks for your help. I am still having some trouble. I don't fully understand the basic concept of how we can take a method that requires one input and make it so it excepts two. I still got the following error when I entered your code.

required: Product found: Product,int reason: actual and formal argument lists differ in length

Also I don't know how to call the 1 from addItem(item, 1); into the %d from System.out.printf.

Thank you very much for your help thus far and any more help is greatly appreciated.