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Java Java Objects Delivering the MVP Applying a Discount Code

rodnel lighty
rodnel lighty
1,090 Points

Please help? I'm a bit stuck. not sure where to go with this. Here is my following code.

Am i suppose to put the applyDiscountCode method on to the new value of discountCode and return it?

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

  public Order(String itemName, int priceInCents) {
    this.itemName = itemName;
    this.priceInCents = priceInCents;
  private String normalizeDiscountCode(String discountCode) {
    discountCode = String.toUpperCase(discountCode);
    return discountCode;

  public String getItemName() {
    return itemName;

  public int getPriceInCents() {
    return priceInCents;

  public String getDiscountCode() {
    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

Hey there!

The goal of this challenge is making sure that discountCode is valid. In your applyDiscountCode method, after normalizing the user entry (upper casing the discountCode), you have to make sure that it only has letters and the '$' character. Only then, if the code is valid, should you replace the instance's discountCode (this.discountCode =...). Also, pay attention to the method's return type! void means you shouldn't return any value. The way you do that is quite similar to the section's video, so check it out one last time before coding the method.

Hope this helps clear any confusion!