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Java Java Objects Delivering the MVP Applying a Discount Code

I might not clear about how to call applyDiscountCode and should I write it like this?

How to fix it, I am a green bean, thank you!

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 void normalizeDiscountCode(String discountCode)
  {
    if(! Character.isLetter(discountCountCode))
    {
     Character.toUppercase(discountCountCode);
     }
     return this.discountCountCode;
   }


}
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"
    }

  }
}
Tony Gemenie
Tony Gemenie
3,781 Points

Hey Li!

Check your Params for normalizeDiscountCode. Don't make it so hard on yourself.

1 Answer

Tony Gemenie
Tony Gemenie
3,781 Points

Sup Li

public void applyDiscountCode(String discountCode) {
    this.discountCode = discountCode;
  }
    private void normalizeDiscountCode(String discountCode)
  {
    if(! Character.isLetter(discountCountCode))
    {
     Character.toUppercase(discountCountCode);
     }
     return this.discountCountCode;

Take a look at applyDiscountCode it should give specific instructions about how to call normalizeDiscountCode from applyDiscountCode in step 1. When you get to Step 2 roll the dice man and play with it. Just don't stop.

Yeah I see, but how I called it in private method? Maybe I should write

private void normalizeDiscountCode(char letter) { letter.applyDiscountCode("abc"); letter.getDiscountCode(); if(! Character.isLetter(letter)) { letter.Character.toUppercase(letter); } return this.letter; }

Can Iļ¼Ÿ is that correct?

I see, but how I called it in private method? Maybe I should write

private void normalizeDiscountCode(char letter) { letter.applyDiscountCode("abc"); letter.getDiscountCode(); if(! Character.isLetter(letter)) { letter.Character.toUppercase(letter); } return this.letter; }

Can Iļ¼Ÿ is that correct?