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Java Java Objects Delivering the MVP Applying a Discount Code

I'm stuck in this challenge. Please help!

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 normalizeDiscountCode(String DiscountCode) { return discount.toUpperCase();

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 normalizeDiscountCode(String DiscountCode){
    return discount.toUpperCase();                                      
public class Example {

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

    Order order = new Order(
            "Yoda PEZ Dispenser",

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

    order.getDiscountCode(); // $ALE

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


1 Answer

Brandon Khan
Brandon Khan
21,619 Points

private String normalizeDiscountCode(String DiscountCode){ return discount.toUpperCase(); }

the issue is your variable getting passed in is DiscountCode but the variable you are returning is discount. This function has no variable in its scope named discount to return. If you want to use the passed in variable you need to use DiscountCode as thats the name of any variable passed into this function. it looks like you are also missing a closing } in the code but not in your question.

private String normalizeDiscountCode(String DiscountCode){ return DiscountCode.toUpperCase(); } < - like this.

Caleb Kleveter
Caleb Kleveter
Treehouse Moderator 37,862 Points

Hey Brandon. I just wanted to let you know I changed your comment to answer. This allows people to upvote it if it is helpful and the OP to mark it as 'best'.

Happy coding and thanks for helping in the forums!