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Java Java Objects Delivering the MVP Applying a Discount Code

Gergő Endrész
Gergő Endrész
7,169 Points
Posted by Gergő Endrész
Gergő Endrész
7,169 Points

WHy doesn't it accept my soultion?

I tried different variations, yet, the system seems not to accept either letter == '$' or letter.equals('$') solutions and throws an error message (Task 1 is no longer passing") as soon as I append my code with the aforementioned code snippets.

Order.java 
public class Order {
  private String itemName;
  private int priceInCents;
  private String discountCode;
  private String normalizeDiscountCode(String code){

     char[] toNormalize = code.toCharArray();

    for (Character letter : toNormalize){
       if (! Character.isLetter(letter) || !(letter == '$')) {
       throw new IllegalArgumentException("Invalid discount code");
       }     
    }  




  return code.toUpperCase();


  }
  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 = this.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"
    }

  }
}

2 Answers

Jethro Ocean
Jethro Ocean
2,458 Points
Jethro Ocean
Jethro Ocean
2,458 Points

I also encountered that problem back then. The problem here is with your conditional statement. You used an OR operator instead of using an AND, thus for example: letter = a, then for the conditions you have set:

!Character.isLetter(letter) will return a 0 and !(letter == '$') will return a 1 (note here that 'a' is not equal to '$')

This does not then comply with the task. Just replace the OR with AND and it should work just fine.

private String normalizeDiscountCode(String discountCode) {

for(char letter : discountCode.toCharArray()) {
  if (!Character.isLetter(letter) && !(letter == '$')) {
    throw new IllegalArgumentException("Invalid discount code");
  }
}
return discountCode.toUpperCase();

}

Gergő Endrész
Gergő Endrész
7,169 Points
Gergő Endrész
Gergő Endrész
7,169 Points

Cheers, it's very kind of you to respond.