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Java Java Objects (Retired) Delivering the MVP Defaulting Parameters

Alfredo Prince
Alfredo Prince
6,175 Points

I have no idea what i'm doing here.

Can anyone offer a little guidance?

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;
  }
}

3 Answers

Almost! You've got to add the new method in the shopping cart class. Try something like this:

// This is already in the Shopping Car Class 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. */ }

// Add something like this public void addItem(Product item,) { addItem(item, 1) }

Then adjust the Example file as needed, if you need to. This way, if a user calls addItem with only an item, it is assumed that only one product is added.

Alfredo Prince
Alfredo Prince
6,175 Points

I eventually got to the same conclusion haha thank you!

The question is asking you to allow users to add only a product, and if no quantity is specified then the program should assume only one of the products was added. Is there a way you can create another addItem() method that would take in only a product, and automatically set the value for quantity to 1? Maybe your new addItem() method can call the currently written addItem() method using a different signature.

Alfredo Prince
Alfredo Prince
6,175 Points

i tried the following and got a wealth of errors. I also tried to pass "item" as a parameter to no avail.

public class ShoppingCart {
  public final int MINIMUM = 1;

  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(){
    addItem(MINIMUM);
    }
  }
}

Any ideas?

Close man. So you need to remember that you don't know the product you're taking in. Your new addItem method should take a product, and then call the previous addItem method.

Try something like this:

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