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Java Java Objects Delivering the MVP Applying a Discount Code

Myra Zubair
Myra Zubair
3,161 Points

Help with applying discount code?

Hey, i keep getting the error: Hmmm...I ran order.applyDiscountCode("h1!") and I expected it to throw an IllegalArgumentException, but it didn't.

Ive ran my code through an IDE and it worked like it should, however it's apparently not working properly here. I cannot find my error. Please help :)

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;
  }

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

  public void applyDiscountCode(String discountCode) {    
    try{
      this.discountCode = normalizeDiscountCode(discountCode);
    }catch (IllegalArgumentException iae){
      System.out.printf("%s", iae.getMessage());
    }
  }
}
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"
    }

  }
}
Vladut Astalos
Vladut Astalos
11,246 Points

Try to put return discountCode.toUpperCase(); into an else block after your if statement.

2 Answers

Myra Zubair
Myra Zubair
3,161 Points

@Vladut Astalos, I tried that, it didn't work since if I put it within the for loop, it doesn't leave a return statement for the normalizeDiscountCode method and it also then doesn't allow task 1 to pass through.

Abua KC
Abua KC
5,932 Points

Your ApplyDiscountCode is not supposed to catch the the exception because @Craig already did that in the Example class. All you need is already there.

public void applyDiscountCode(String discountCode) {

this.discountCode = normalizeDiscountCode(discountCode);

}