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Java Java Objects Delivering the MVP Applying a Discount Code

Why the code doesn't work.

It is asking if the string contain legal char , i tried to convert a string to array of char then loop through it then check if the it is valid char. I'm not sure if I did right.

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) {
  char[] letters = discountCode.toCharArray();
  String upper = "";
  for(char l: letters){
     if(Character.isLetter(l)){
       upper += l;
    }else{
      throw new IllegalArgumentException("Invalid discount code");
    }
  }
  return upper.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"
    }

  }
}

1 Answer

Brendan Whiting
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.a{fill-rule:evenodd;}techdegree seal-36
Brendan Whiting
Front End Web Development Techdegree Graduate 84,738 Points

'$' isn't a letter, but this challenge wants it to be a valid character, so you need to check it as well in your condition, something like this:

     if (Character.isLetter(l) || l == '$') {
       upper += l;
     }

Thanks for your help , I missed this part of if condition.