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Java Java Objects Delivering the MVP Applying a Discount Code

Omar Lahiani
Omar Lahiani
Courses Plus Student 1,123 Points

Throwing exception

Hi !

I'm new to this website so I'mma try my best to explain the problem I'm having , so in this task I'm supposed to only let the user type in a string that contains letters or '$' , so I wrote a for loop at first to go through the string char by char , and If NOT a letter or NOT a '$' symbol encounters , it should throw an exception saying ("invalid discount code") , Else the program should upper case and return the string as in task 1 . Here the error message I keep getting ( Oops! It looks like Task 1 in no longer passing ..) Ps : I tried toCharArray() instead of the for loop , It doesn't work as well :/ , can someone help me figure this out ? I'd appreciate it :)

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){

    for (int i = 0; i < discountCode.length(); i++){
    char c = discountCode.charAt(i);
      if (!Character.isLetter(c) ||c!='$'){
      throw new IllegalArgumentException("Invalid discount code");   
    this.discountCode = discountCode.toUpperCase();
    return this.discountCode;

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

Rares Conea
Rares Conea
Courses Plus Student 15,000 Points

Hi Omar,

Your code will work if you chage || with your && in your if statement.