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Java Java Objects Delivering the MVP Applying a Discount Code

Leo Marco Corpuz
Leo Marco Corpuz
18,975 Points

Syntax error in my code

The error arrow points to my letter!="$" on line 28 but I'm guessing it's something else.

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){
    for(char letter:discountCode.toCharArray()){
        if(!Character.isLetter(letter)||letter!="$" ){
            throw new IllegalArgumentException("Invalid discount code");
        }
    }
      return discountCode.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"
    }

  }
}

2 Answers

Emmanuel C
Emmanuel C
10,636 Points

Hey, So I noticed 2 things. First, your syntax error has to do with comparing a string and char. When you put $ in double quotes, it makes it a string while the variable letter is a char. You can simply use single quotes instead to make '$' a char

Second, in your if statement youre checking if its not a letter OR its not equal to '$' . This will fail in cases where it shouldnt. In the first test "abc" is passed in. 'a' is a letter so that part is false, but 'a' != '$' will return true, and since youre using OR, the whole if statement is true and the error is thrown. Changing the OR to an AND will fix that. And the rest of your code looks good.

Good luck

Sean M
Sean M
7,344 Points

Single characters such as n or z or $ should be inside single quotation marks: '$'