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Java Java Objects Delivering the MVP Applying a Discount Code

Posted by kumbirai mangwanda
kumbirai mangwanda
1,628 Points

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.

What is that i'm doing wrong?

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 char normalizeDiscountCode(char letter) {
    this.letter = letter.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"
    }

  }
}

1 Answer

Zhaopeng Wang
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PLUS
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Zhaopeng Wang
Full Stack JavaScript Techdegree Graduate 32,210 Points
Zhaopeng Wang
.a{fill-rule:evenodd;}techdegree seal-36
Zhaopeng Wang
Full Stack JavaScript Techdegree Graduate 32,210 Points
  • First, there is no variable letter defined within the Order class, therefore, this.letter is not correct.
  • Second, the instruction indicates that you need to call the normalizeDiscountCode within the applyDiscountCode method
  • Also, normalizeDiscountCode should take a String type parameter and returns String as result
public class Order {
  private String itemName;
  private int priceInCents;
  private String discountCode;

  private String normalizeDiscountCode (String code){
    return code.toUpperCase();
  }

  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);
  }
}