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Java Java Objects Delivering the MVP Applying a Discount Code

Basel Kanaan
Basel Kanaan
4,458 Points

hi please i need a help here i tried everything but still cant get the right answer

idk what should i do i tried everything i need someone to help me here

public class Order {
  private String itemName;
  private int priceInCents;
  private String discountCode;

  private String  normalizeDiscountCode(String discountCode){
    this.discountCode = discountCode.toUpperCase();
if (this.discountCode.indexOf(discountCode)== -1 || this.discountCode.indexOf(discountCode)!='$')
{ throw new IllegalArgumentException("Invalid discount code");}

    return this.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() {
     try{ normalizeDiscountCode(discountCode);}
    catch(IllegalArgumentException iae){
    System.out.printf("Invalid discount code.", iae.getMessage());}

    return discountCode;

  public void applyDiscountCode(String discountCode) {
    this.discountCode = discountCode;
public class Example {

  public static void main(String[] args) {
    // This is here just for example use cases.

    Order order = new Order(
            "Yoda PEZ Dispenser",

    // These are valid.  They are letters and the $ character only
    order.getDiscountCode(); // ABC

    order.getDiscountCode(); // $ALE

    try {
      // This will throw an exception because it contains numbers
    } catch (IllegalArgumentException iae) {
      System.out.println(iae.getMessage());  // Prints "Invalid discount code"
    try {
      // This will throw as well, because it contains a symbol.
    }catch (IllegalArgumentException iae) {
      System.out.println(iae.getMessage());  // Prints "Invalid discount code"


1 Answer

Steven Parker
Steven Parker
229,017 Points

The instruction say the new method should "return the uppercase version" but since it wasn't explicitly asked for, it should probably not modify this.discountCode along the way.

Then, applyDiscountCode will need to call the new method to get the value to assign.

For task 2, you'll probably want a loop to check each letter. You likely won't need the "indexOf" method, since it would be better suited to check for something required instead of disallowed.