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Java Java Objects Delivering the MVP Applying a Discount Code

Chastain Marchildon
Chastain Marchildon
905 Points

Task 1 is no longer passing? normalized discount code part 2

Added a for each loop to check for a letter or the $ sign, and throw an exception if one of the other isnt true, now the normalizedDiscountCode method isnt passing and I can not figure out why.

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

  private String normalizeDiscountCode(String discountCode){

    for(char y : discountCode.toCharArray()){
     if( !Character.isLetter(y) || discountCode.indexOf('$')==-1){
        throw new IllegalArgumentException("Invalid discount code");
     }//end of if
    }//end of for

    return 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) {
    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"
    }

  }
}

2 Answers

Christian Thieme
Christian Thieme
9,448 Points

Without diving too deep into your code I can tell that your for loop is not doing what you want. The way you have this written, you want to check if both of these things are NOT true, so trying using the "and" operator and changing your second check to != instead of ==. Try this:

for(char y : discountCode.toCharArray()){
 if( !Character.isLetter(y) && discountCode.indexOf('$')!=-1){
    throw new IllegalArgumentException("Invalid discount code");
 }//end of if
}//end of for

return discountCode.toUpperCase();

}

Hopefully this will get you going in the right direction.

Best of luck!

Christian Thieme
Christian Thieme
9,448 Points

Sorry. My last answer was wrong slightly. Additionally, we want to make the discount code uppercase before it it run through the for loop. It should look something like this:

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

Hope this helps!