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Java Java Objects Delivering the MVP Applying a Discount Code

James Dunn
James Dunn
3,041 Points

Task 1 no longer working.

So I got part 1 down. After a lot of previewing for errors, I got part 2 where it "should" work but every time I check, it says part 1 no longer works.

I go back recheck part 1 it passes when I hit check.

So the question is, what do I do?

Thanks.

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;
  }

  public void applyDiscountCode(String discountCode) {

    try {
      this.discountCode = normalizeDiscountCode(discountCode);
    } catch (IllegalArgumentException e) {
      e.getMessage();
    }
  }

  private String normalizeDiscountCode(String discountCode) {
    discountCode = discountCode.toUpperCase();

    for(char temp : discountCode.toCharArray()) {

      if(! Character.isLetter(temp) || temp != '$') {
        throw new IllegalArgumentException("Invalid discount code");
      }//End of If
    }//End of For
  return discountCode;
  }//End of normalizeDiscountCode
}
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

Anders Björkland
Anders Björkland
7,481 Points

Hi James, I had the exact same problem as you are having now, and I see you did exactly as I did. Do you recall what you changed between task 1 and task 2? It was adding the if-statement that checks if the discount code is valid. A character in the string should be either an '$' or a letter. It is here that semantics and logic seem to clash. Because you will now throw a new IllegalArgumentException in the case of the String "$foo". Why? The first char - '$' - is not a letter. The rest of the characters would also throw an exception because they are not a '$'. This is what you wrote in the method normalizeDiscountCode:

if(! Character.isLetter(temp) || temp != '$')

See if you can revise it. Good luck!

Melodie 1
Melodie 1
3,931 Points

if(! Character.isLetter(temp) || temp != '$') try changing || to &&