Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

Java Java Objects (Retired) Delivering the MVP Defaulting Parameters

i have to add things to the cart

well i can't get it right i tried everything i can't get it done its the hardest exercice i ever did

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);
     public void addItem(Product item) { int mQuantity = 1; 
   public void addItem(Product item, int quantity) { System.out.printf("Adding %d of %s to the cart.\n", quantity, item.getName());
         }
                }

    /* 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.
     */
  public void addItem(Product item, int quantity) { System.out.printf("Adding %d of %s to the cart.\n", quantity, item.getName());}
    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
    */

  }

}
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. 
    */

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

Seth Kroger
Seth Kroger
56,413 Points

You have a method nested inside another method (inside the other methods curly braces), and Java doesn't allow that. The methods should be side-side inside the class instead.

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) {
   addItem(item,1);
}

You also don't need the methods duplicated in Example.java main() either.

Kourosh Raeen
Kourosh Raeen
23,733 Points

You have the right code added to ShoppingCart.java:

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

However, in the file Example.java all you need to do is to uncomment this line:

cart.addItem(dispenser);

The method definitions for addItem should not be in Example.java. Here's the code:

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);
  }

}

thx for the ShoppingCart but the rest i dont understand do i have to just un-comment the cart.addItem(dispenser); and the third code u send me its in the example.java if yes then i only have to un-comment the cart.addItem(dispenser) what about the third one " Product.java" sorry i m troubling you and thx a lot i appreciate :D

Kourosh Raeen
Kourosh Raeen
23,733 Points

The are no changes to the Product.java file. And the only change to Example.java is uncommenting cart.addItem(dispenser);

thx a lot u literally saved me i appreciate it a lot !

Kourosh Raeen
Kourosh Raeen
23,733 Points

Also, as Seth Kroger mentioned, make sure the definition of addItem(Product item) is not inside the definition of addItem(Product item, int quantity). It should be exactly as he posted below.