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Java Java Objects Delivering the MVP Applying a Discount Code

Posted by Carla Barrios
Carla Barrios
636 Points

I'm stuck in this challenge. Can someone tell me what am I doing wrong?

For this first task, create a new private method named normalizeDiscountCode. It should take the discount code that is passed into the method and return the uppercase version. Call it from the current applyDiscountCode method and set this.discountCode to the result.

private String ApplyDiscountCode(String discountCode){
this.discountCode = normalizeDiscountCode(String discountCode); return discountCode.toUpperCase();

Order.java 
public class Order {
  private String itemName;
  private int priceInCents;
  private String discountCode;

  public Order(String itemName, int priceInCents) {
    this.itemName = itemName;
    this.priceInCents = priceInCents;
  }

  public String getItemName() {
    return itemName;
  }

  public int getPriceInCents() {
    return priceInCents;
  }

  public String getDiscountCode() {
    return discountCode;
  }

  public void applyDiscountCode(String discountCode) {
    this.discountCode = discountCode;
  }
  private String ApplyDiscountCode(String discountCode){  
    this.discountCode = normalizeDiscountCode(String discountCode);
    return discountCode.toUpperCase();
}
 }
Example.java 
public class Example {

  public static void main(String[] args) {
    // This is here just for example use cases.

    Order order = new Order(
            "Yoda PEZ Dispenser",
            600);

    // These are valid.  They are letters and the $ character only
    order.applyDiscountCode("abc");
    order.getDiscountCode(); // ABC

    order.applyDiscountCode("$ale");
    order.getDiscountCode(); // $ALE


    try {
      // This will throw an exception because it contains numbers
      order.applyDiscountCode("ABC123");
    } catch (IllegalArgumentException iae) {
      System.out.println(iae.getMessage());  // Prints "Invalid discount code"
    }
    try {
      // This will throw as well, because it contains a symbol.
      order.applyDiscountCode("w@w");
    }catch (IllegalArgumentException iae) {
      System.out.println(iae.getMessage());  // Prints "Invalid discount code"
    }

  }
}
Teacher Russell
Teacher Russell
16,873 Points
Teacher Russell
Teacher Russell
16,873 Points

Is it possible you've misnamed your function? Should be private String normalizeDiscountCode.

1 Answer

simeon
simeon
1,549 Points
simeon
simeon
1,549 Points

I was really stuck on this challenge as well ;) What I'm thinking to spot in your code are a couple of the following points:

First it looks like the last method is indeed misspelled. It should be private String normalizeDiscountCode (String discount)

Secondly, the task asks us to call normalizeDiscountCode inside the applyDiscountCode method. Also set that call equal to this.discountCode.

I myself did not change the applyDiscountCode into a void method, but left it returning the discountCode, but I guess that is just a matter of what you want.

Hope it helps and enables you to continue with the challenges!

  public String applyDiscountCode(String discountCode) {

    this.discountCode = normalizeDiscountCode(discountCode);

    return discountCode;

  }

  private String normalizeDiscountCode(String discountCode) {

    return discountCode.toUpperCase();

  }