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Java Java Objects Delivering the MVP Applying a Discount Code

A Coder
A Coder
2,362 Points

Code is not acceptable despite the program doing exactly what the exercise asks

My code does not pass the check, despite the code working as the exercise intends in the preview. "h1!" is passed in and is recognized, and the IllegalArgumentException runs during the normalize function, but the "Recheck Work" always fails with the same error, saying that h1! did not throw an IllegalArgumentException.

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)
  {


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

    return discountCode;
  }

  public void applyDiscountCode(String discountCode) 
  {
    try
    {
      System.out.printf("%s %n", discountCode);
      discountCode = discountCode.toUpperCase();
      discountCode = normalizeDiscountCode(discountCode);
      System.out.printf("%s %n", discountCode);
      this.discountCode = discountCode;
    }
    catch(IllegalArgumentException iae)
    {
      System.out.printf("%s %n", iae.getMessage());
    }
  }
}
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
218,596 Points

Part of the task 1 instructions for "normalizeDiscountCode" say "It should take the discount code that is passed into the method and return the uppercase version.", but this code doesn't seem to convert the value to upper case.

Then, only two minor changes are asked to be made to "applyDiscountCode", but here a number of extra changes have been made that alter what the method does.

It's important to follow challenge instructions exactly, and to also not change anything they don't ask for.

A Coder
A Coder
2,362 Points

I've retried the challenge with the advice given and it's worked! I'll remember to read the question more carefully from now on. Thank you!