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Java Java Objects Delivering the MVP Applying a Discount Code

Need help with my code. Wondering why it doesn't throw IllegalArgumentException

Pretty sure that my code should work but somehow it doesn't. Need help if anyone can point out if there's something wrong with my code. Thank you.

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);
    }catch(IllegalArgumentException iae){

  private String normalizeDiscountCode(String discountCode){
    boolean accepatable = false;
    for( char c : discountCode.toCharArray()){
      if(Character.isLetter(c) || c == '$') {
        accepatable = true;
        accepatable = false;

      return discountCode.toUpperCase();
      throw new IllegalArgumentException("Invalid discount code");
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

Steven Parker
Steven Parker
218,596 Points

The instructions don't ask you to add a "try/catch", and by catching the exception yourself it prevents the validator from detecting it.

Thank you for pointing it out. Still trying to familiarize with the syntax.