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Java Java Objects Delivering the MVP Applying a Discount Code

Jethro Ocean
Jethro Ocean
2,458 Points

normalizedDiscount Help!

I don't know what is wrong :( please help.

Order.java
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) {

    for (char let : discountCode.toCharArray() ) {
      if ( (!Character.isLetter(let)) || (discountCode.indexOf('$') == -1) ) {
        throw new IllegalArgumentException("Invalid discount code");
      }
    }

    String result = discountCode.toUpperCase();
    return result;
  }

  public String getItemName() {
    return itemName;
  }

  public int getPriceInCents() {
    return priceInCents;
  }

  public String getDiscountCode() {
    return discountCode;
  }

  public void applyDiscountCode(String discountCode) {
    this.discountCode = normalizeDiscountCode(discountCode);
  }
}
Example.java
public class Example {

  public static void main(String[] args) {
    // This is here just for example use cases.

    Order order = new Order(
            "Yoda PEZ Dispenser",
            600);

    // These are valid.  They are letters and the $ character only
    order.applyDiscountCode("abc");
    order.getDiscountCode(); // ABC

    order.applyDiscountCode("$ale");
    order.getDiscountCode(); // $ALE


    try {
      // This will throw an exception because it contains numbers
      order.applyDiscountCode("ABC123");
    } catch (IllegalArgumentException iae) {
      System.out.println(iae.getMessage());  // Prints "Invalid discount code"
    }
    try {
      // This will throw as well, because it contains a symbol.
      order.applyDiscountCode("w@w");
    }catch (IllegalArgumentException iae) {
      System.out.println(iae.getMessage());  // Prints "Invalid discount code"
    }

  }
}
Craig Dennis
Craig Dennis
Treehouse Teacher

Hi Jethro Lee Ocean !

What error message are you getting?

One thing I see is that you could check each of those letters going through to see if it is a '$' instead of checking to see if it is in the entire string. One reason is because !!#@S$ would pass part the second side of the OR.

That make sense?

1 Answer

Jethro Ocean
Jethro Ocean
2,458 Points

Thanks for your answer! I actually have completed this challenge already. I comparing the '$' per letter in the conditional statement rather than the whole string.