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Java Java Objects Delivering the MVP Applying a Discount Code

I'm stuck. My weakness with Java at the moment is with objects. Please help.

My weakness at the moment is with objects. Please help. I'm stuck.

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

  public Order(String itemName, int priceInCents) {
    Order order = new Order(20);
    this.itemName = itemName;
    this.priceInCents = priceInCents;

    order.applyDiscountCode("abc");
    order.getDiscountCode(); // ABC

    order.applyDiscountCode("$ale");
    order.getDiscountCode(); // $ALE
  }

  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) {
    for (char letter : discountCode.toCharArray()) {

      if (Character.isLetter(letter)) {
        System.out.println("Code is a letter. Valid code.");      //this line of code is unnecessary. I just wrote it to make it clear.
      } else if(letter == '$') {
        System.out.println("Code is a dollar sign. Valid code.");   //this line of code is unnecessary.
      } else {
        throw new IllegalArgumentException("Invalid discount code");
      }

    }
    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"
    }

  }
}

1 Answer

Sean M
Sean M
7,344 Points

What seems to be the problem?