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Java Java Objects Delivering the MVP Applying a Discount Code

Hi. Can someone please help me with my exception here?

1st task: 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.

2nd task: In the normalizeDiscountCode verify that only letters or the $ character are used. If any other character is used, throw a IllegalArgumentException with the message Invalid discount code.

For some reason my code tells me that task one is no longer correct whereas when i go back to task one and click "check work" it tells me that my code is valid and puts me back onto task 2. Any help would be much appreciated.

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

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

  private String normalizeDiscountCode(String discountCode) {
   String upperDiscountCode = discountCode.toUpperCase();
   String acceptedDiscountCode = "ABCDEFGHIJKLMNOPQRSTUVWXYZ$";

   for (char i : discountCode.toCharArray()) {
     for (char j : acceptedDiscountCode.toCharArray()) {
       if (i == j) {
         return upperDiscountCode;
       else {
         throw new IllegalArgumentException("Invalid discount code"); 
     return upperDiscountCode; 

  public String getItemName() {
    return itemName;

  public int getPriceInCents() {
    return priceInCents;

  public String getDiscountCode() {
    return discountCode;

  public void applyDiscountCode(String discountCode) {
    String upperDiscountCode = normalizeDiscountCode(discountCode);
    this.discountCode = upperDiscountCode;
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

Craig Dennis
Craig Dennis
Treehouse Teacher

Hmmm... why the nested for loops? return will exit out the method immediately.

Have you seen Character.isLetter ?

(Hope that hint helps!)

Thanks!! I got it :)