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Java Java Objects Delivering the MVP Applying a Discount Code

mohamadreza azadi
mohamadreza azadi
5,167 Points

stuck here :\ has anyone else

unfortunately i'm stuck here for 1 day ;| in this exercise task2 say: only letter and "$" you can use .

i done letter and i dont know what's that metod to define $ can use it

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) {
  discountCode=normalizeDiscountCode(discountCode);
    this.discountCode = discountCode;
  }
  private String  normalizeDiscountCode(String discountCode){
    String capital="";

    for(char letter:discountCode.toCharArray()){
           if(!Character.isLetter(letter)){

      throw new IllegalArgumentException("Invalid discount code");
           }

      letter=Character.toUpperCase(letter);
      capital=capital+letter;
    }


    return capital;
  }
}
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

Isaiah Marin
Isaiah Marin
11,971 Points

Hi, I noticed you didn't check to see if the discount code is a '$' symbol. The challenge states that the discount code must be a letter or a '$'. And to throw an exception if the discount code is not a letter or '$'.

So maybe in your if statement include something like " (!Character.isLetter(letter) && letter != '$') ."

Anyhow, I here is code that worked for me. I hope it helps.

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) {
    String normalizedCode = "";

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

      if (Character.isLetter(letter) || letter == '$') {
        normalizedCode += Character.toUpperCase(letter);
      } else {
        throw new IllegalArgumentException("Invalid discount code");
      }

    }

    return normalizedCode;
  }  
}