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Java Java Objects Delivering the MVP Applying a Discount Code

I don't get the question

Task 1

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;

  public void normalizeDiscountCode(String 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

Tonnie Fanadez
.a{fill-rule:evenodd;}techdegree seal-36
Tonnie Fanadez
UX Design Techdegree Graduate 22,796 Points

Hello YZ L

Good question and this is how I did it step by step.

1. Declare the private method

  • the return type is a String and not void since the string is returning a String in uppercase
  • the method takes String discountCode as a parameter
  • use the return keyword to return a String
  • use String's class _toUpperCase() method to convert the discount code to Caps.
private String normalizeDiscountCode ( String discountCode) {

return discountCode.toUpperCase() ;

2. Use normalizeDiscountCode() inside the applyDiscount()

  • have commented the first line inside applyDiscountCode() so that the compiler can ignore the line
  • have set the this.discountCode member variable to equal the value returned from normalizeDiscountCode()
  • this will make the discountCode to be in Caps.
public void applyDiscountCode(String discountCode) {
    //this.discountCode = discountCode;

this.discountCode = normalizeDiscountCode(discountCode);

I hope this helps.


Thank you!!