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Java Java Objects Delivering the MVP Applying a Discount Code

Posted by Sachini Hansini Nawalaella
Sachini Hansini Nawalaella
2,842 Points

applying a discount code

For this first task, create a new private method named normalizeDiscountCode. It should take the discount code that is passed into the method and return the uppercase version. Call it from the current applyDiscountCode method and set this.discountCode to the result.

Please help me with my code.i can not find my errors

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

Richard Lambert
PLUS
Richard Lambert
Courses Plus Student 7,180 Points
Richard Lambert
Richard Lambert
Courses Plus Student 7,180 Points

Hello mate,

  1. Once normalizeDiscountCode(String discountCode) has been created, call it from within applyDiscountCode(String discountCode), passing discountCode as the argument, and assigning the return value to this.discountCode.
  2. The extra closing brace will cause a compile time error.
  3. I find that applying a consistent code style allows me to identify errors more effectively.
Order.java 
    public void applyDiscountCode(String discountCode) {
        this.discountCode = discountCode;    // (1)
    }
}    // (2)

    private String normalizeDiscountCode(String discountCode) {   // (3)
        String UpperCase = discountCode.toUpperCase();
        for (char ch : discountCode.toCharArray()) {
            if (! Character.isLetter(ch) && ch != '$') {
                throw new IllegalArgumentException("Invalid discount code.");
            }
        }  
        return UpperCase;
    }

Hope this helps

Sachini Hansini Nawalaella
Sachini Hansini Nawalaella
2,842 Points

thank you for showing me my errors.