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Java Java Objects Delivering the MVP Applying a Discount Code

Jaeden Eldred
Jaeden Eldred
1,038 Points

unsure how to not throw an exception if $ is given through string.

I have written a for loop to verify that only letters are in the string, however I am unsure of how to check to see if the $ is there and to make sure it is accepted. If I could get some direction on this that would be great. Thanks

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){
  this.discountCode = discountCode;

    char [] chars = discountCode.toCharArray();
    for (int i = 0; i < chars.length; i++){
    char chars2 = chars[i];
      if (!Character.isLetter(chars2)){
        throw new IllegalArgumentException("incorrect symbol");
      }
    }

        discountCode = discountCode.toUpperCase();
      return 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

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

You can add another boolean condition after !Character.isLetter(chars2) with the and && operator:

if (!Character.isLetter(chars2) && chars2 != '$'){
    throw new IllegalArgumentException("incorrect symbol");
}