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Java Java Objects Delivering the MVP Applying a Discount Code

challenge #2 I am just not getting what to do next

This is my code, I am not getting what am i doing wrong

Order.java
public class Order {
  private String itemName;
  private int priceInCents;
  private String discountCode;
   private String normalizeDiscountCode( String discountCode) {
    this.discountCode = discountCode.toUpperCase();
    return this.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);
    char dollar = '$';
    if(!Character.isLetter(discountCode.charAt(0)) || !discountCode.contains("$") ) {
      throw new IllegalArgumentException("Invalid discount code");
    }

  }

}
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

Hey there,

First:

  • Your validation should be inside the normalizeDiscountCode() method

Second:

  • You are not returning anything on your applyDiscountCode() method

Logic:

  • Example.java should call applyDiscountCode() passing the codes.
  • applyDiscountCode() should then call normalizeDiscountCode() passing the same code
  • normalizeDiscountCode() should then process the code (validating and normalizing it) and return it in uppercase to applyDiscountCode() that would then return it to Example.java

I hope it helps.