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Java Java Objects Delivering the MVP Applying a Discount Code

Mehtab Kayani
Mehtab Kayani
3,179 Points

Im stuck and cannot figure out what Im missing.

Need some help.

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 = normalizeDiscountCode(discountCode);


  private String normalizeDiscountCode(String discountCode){
    if(!discountCode.equalsIgnoreCase(discountCode) && !discountCode.equalsIgnoreCase("$")){
        throw new IllegalArgumentException("Invalid discount code.");
    return  discountCode.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"


2 Answers

Tyler B
Tyler B
5,787 Points

This line:


is confusing if discountCode = "A" you're asking Opposite of (Does "A" equal "A" OR "a")

I believe what you wanted to do is leverage Character.isLetter() to validate your value. Hope that helps!

Cole Baker
Cole Baker
631 Points

I'm stuck on the same problem. If Character.isLetter() is used, how would you implement it to compare it through the String discountCode?