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Java Java Objects (Retired) Delivering the MVP Defaulting Parameters

Chris Ayers
Chris Ayers
554 Points

Help on this problem

I am a bit confused on this problem. Is this dealing with interfaces or polymorphism? If so then that might help me out! If not what would be a good way to start this problem? I am assuming it is wanting the example to take in any product and any price by using the other two classes but I really am a bit confused on all of this.
Hope you can help me out! Thanks

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;
  }
}

1 Answer

Simon Coates
Simon Coates
28,694 Points

uncomment the method calls, and adjust the shopping cart (see below):

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);
  }
}

As they state the code for adding an item is complicated (the stuff they omitted), it makes sense to have the second addItem method use the first.

Chris Ayers
Chris Ayers
554 Points

Thank you this helps out, I was definitely think way to hard on this one!

Thanks again for the help and explaining it!