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Java Java Objects Delivering the MVP Applying a Discount Code

Xuanzheng Lin
Xuanzheng Lin
2,466 Points

Failed in Task 1 when I am in Task 2

The instruction of task 2 is "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." However, i cannot pass task 2 because it says task 1 is failing lol.

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

  // class code omitted for brevity

  public void applyDiscountCode(String discountCode){
    String want = normalizeDiscountCode(discountCode);
    this.discountCode = want;
    /*try {
      String want = normalizeDiscountCode(discountCode);
      this.discountCode = want;
    } catch (IllegalArgumentException iae) {

  private String normalizeDiscountCode (String discountCode) {
    String upper = "";
    for (char letter : discountCode.toCharArray()) {
      if (! Character.isLetter(letter) || letter != '$') {
        throw new IllegalArgumentException("Invalid discount code.");
      } else if (Character.isLetter(letter)) {
        upper += Character.toUpperCase(letter);
      } else {
        upper += letter;
    return upper;

1 Answer

Hi there,

I think there's another thread on this challenge where there's a suggested solution.

Here, you've done a similar test using || rather than && and then have uppercased each letter in turn and reassembled the word one character at a time. There's no need to do that. The if statement filters out invalid codes and throws an error.

If that doesn't happen, just return the original discountCode parameter chained to .toUpperCase().