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Java Java Objects Delivering the MVP Applying a Discount Code

Hai Phan
Hai Phan
2,442 Points

Need help in challenge task 2

I think the logic is acceptable here. What is wrong with my code?

Note: there is no compiling error.

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

  private String normalizeDiscountCode(String discountCode) {
    for (char letter : discountCode.toCharArray()) {
        if (! Character.isLetter(letter)) {
        if (letter != '$'){
            throw new IllegalArgumentException("Invalid discount code");
        }
      }
    }
    return this.discountCode = discountCode.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) {
    try {
        discountCode = normalizeDiscountCode(discountCode);
    } catch(IllegalArgumentException ex) {
        System.out.println(ex.getMessage());
    }
    this.discountCode = 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

Steven Parker
Steven Parker
215,984 Points

You got a bit too fancy in task 1 — the instructions did not ask you to use a "try/catch" in "applyDiscountCode".

But since you did, it handles the exception generated by the task 2 code. And that prevents the challenge from being able to confirm that the task 2 code is working.