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Java Java Objects Delivering the MVP Applying a Discount Code

Bhawani Shankar
Bhawani Shankar
954 Points
Posted by Bhawani Shankar
Bhawani Shankar
954 Points

WHY MY CODE IS NOT WORKING

Help me code not working

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) {
    this.discountCode = normalizeDiscountCode(discountCode);
  }
  private String normalizeDiscountCode(String discountCode){
    if(!discountCode.matches"(A-Za-z$)+");
       throw new IllegalArgumentException("Invalid discountCode");
    return discountCode.toUpperCase();
  } 
}
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

andren
andren
28,558 Points
andren
andren
28,558 Points

There are some issues with your code:

  1. You are missing parenthesis for the matches method, in other words there should be parenthesis wrapped around the string that you are passing into the matches method.

  2. You are missing square brackets around this "A-Za-z$" part of your regex, parenthesis is used to indicate a capture group which is not actually something that is needed for the test you are writing, square brackets are used to indicate that you want to match any character or character range found within the brackets.

  3. You have a semicolon ; at the end of your if statement that does not belong there, and ends up ending the if statement prematurely.

If you add the parenthesis around the string, replace the parenthesis within the string with square brackets and remove the semicolon that follows the if statement like this:

private String normalizeDiscountCode(String discountCode){
    if(!discountCode.matches("[A-Za-z$]+"))
        throw new IllegalArgumentException("Invalid discountCode");
    return discountCode.toUpperCase();
}

Then your code will work.

Edit: Added info about the wrongly placed semicolon that I forgot to mention.