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Java Java Objects Delivering the MVP Applying a Discount Code

RAHUL RAO
RAHUL RAO
27,748 Points

Illegal Argument Exception error while checking work

please correct my error not able to rectify where am i making mistake.

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){
   String upperDiscountCode = discountCode.toUpperCase();  

    for( char letter : upperDiscountCode.toCharArray()){
     if(!Character.isLetter(letter) || upperDiscountCode.indexOf('$') < 0){

       throw new IllegalArgumentException("invalid letter is present");
     }

    }

    return upperDiscountCode;

  }
}
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

Lena Hand
PLUS
Lena Hand
Courses Plus Student 1,575 Points

The logic in your if statement is off a bit. When comparing for the '$' you don't need to find the indexOf where it is, you need to see if it exists in the index you're checking. A simple evaluation would work here (a == b).

Additionally, you want to be using matching logic in both checks, ie, check against your letter variable in both cases.