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Java Java Objects Delivering the MVP Applying a Discount Code

Gonzalo Torres del Fierro
PLUS
Gonzalo Torres del Fierro
Courses Plus Student 16,751 Points
Posted by Gonzalo Torres del Fierro
Gonzalo Torres del Fierro
Courses Plus Student 16,751 Points

normalizing discountCode $ or letter are alowed..

hello, i stuck, i got some ideas to go forward, but i would like to have more help on this....

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 = normalizeDiscountCode(discountCode);
  }

  private String normalizeDiscountCode(String discountCode){
    return discountCode.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"
    }

  }
}

2 Answers

J.D. Sandifer
J.D. Sandifer
18,813 Points
J.D. Sandifer
J.D. Sandifer
18,813 Points

Check out the previous video again - especially focus on Craig's normalizeGuess() method you can see at about 9:30 in the video.

Using that as a starting point for your normalizeDiscountCode() method, you just have to add a couple things:

  1. Your method needs to check every character in a String, not just one character. (Add a loop.)
  2. Your method needs to include the '$' character as an acceptable option. (Your test should see if every character is a letter OR the dollar sign. Hint, hint.)

Beyond that, just tweak things - like the exception that's thrown - to match your challenge.

Gonzalo Torres del Fierro
PLUS
Gonzalo Torres del Fierro
Courses Plus Student 16,751 Points
Gonzalo Torres del Fierro
Gonzalo Torres del Fierro
Courses Plus Student 16,751 Points

thx J.D. very kind, i got an idea, can you help me back on this point? i got this on mind....but i got error going back all the time...please!!

private String normalizeDiscountCode(String discountCode){

for( char letter :discountCode.toCharArray()){
  check1 = Character.isLetter(letter);
  check2 = letter=='$';
  if( !check1 ){
     throw new IllegalArgumentException(letter + " Invalid discount code");
                         }
    if (!check2){
     throw new IllegalArgumentException(letter + " Invalid discount code");
                         }

} return discountCode.toUpperCase(); } }