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Java Java Objects Delivering the MVP Applying a Discount Code

Ryan Barone
Ryan Barone
7,079 Points

Having trouble verifying that only letters or the '$' character are used when normalizing my variable

I keep getting the message that task one is now not working. I understand that it is because my code is getting hung up in my if statement, and not running through to my return line. I know that the first half of my if statement is correct in that if the character value in my discountCode variable doesn't equal a letter, it will throw the exception. However, the second half of my if statement is what I keep getting hung up on. I don't understand why the second half is wrong in which I am trying to say that if that character value doesn't equal '$', throw the exception.

EDIT:

Error has been fixed.

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;
  }

  public String getItemName() {
    return itemName;
  }

  public int getPriceInCents() {
    return priceInCents;
  }

  public String getDiscountCode() {
    return discountCode;
  }

  private String normalizeDiscountCode(String discountCode){
    discountCode = discountCode.toUpperCase();  
    for (char letter : discountCode.toCharArray()){
       if (discountCode.indexOf(letter) == -1 && letter != '$'){
          throw new IllegalArgumentException("Invalid discount code");  
    }
    }
    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"
    }

  }
}

1 Answer

David Park
David Park
1,953 Points

For the second half of your "if" statement, you're taking the indexOf your letter. You actually want to just see if it's equivalent (or not equivalent for that matter)

Hope this bit helps.

Ryan Barone
Ryan Barone
7,079 Points

Thanks David!

I changed the second half of the if statement so that it is seeing if letter is equivalent instead of the indexOf discountCode. I understand my mistake there. That did fix the error, however, the exception is still not being thrown.