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Java Java Objects Delivering the MVP Applying a Discount Code

Lucian Ciopec
Lucian Ciopec
12,778 Points

Please provide solution

I do not understand why my code is considered not to be working ...

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; }

private String normalizeDiscountCode(String discountCode) {

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

}

public void applyDiscountCode(String discountCode) { try{ String normalizedCode = normalizeDiscountCode(discountCode); this.discountCode = normalizedCode; } catch (IllegalArgumentException iae) { System.out.printf("%s%n",iae.getMessage()); } } }

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;
  }

  private String normalizeDiscountCode(String discountCode) {
    for(char letter : discountCode.toCharArray()){
      if (!(Character.isLetter(letter) || letter=='$')){
        throw new IllegalArgumentException ("Invalid discount code");
      }
    }
    return discountCode.toUpperCase();
  }

  public void applyDiscountCode(String discountCode) {
    try{
    String normalizedCode = normalizeDiscountCode(discountCode);
    this.discountCode = normalizedCode;
    } catch (IllegalArgumentException iae) {
      System.out.printf("%s%n",iae.getMessage());
    }
  }
}
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

andren
andren
28,558 Points

Your normalization code is correct, but you are not meant to catch the "IllegalArgumentException" on your own. The task instruction only asked you to call the normalization method, not to catch any exceptions it might throw.

The challenge checker expects that exception to be thrown for some of the values it will pass to your code, if you catch it on your own then it will never reach the challenge checker and will therefore always be marked as wrong.

So the solution looks like this:

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;
  }

  private String normalizeDiscountCode(String discountCode) {
    for(char letter : discountCode.toCharArray()){
      if (!(Character.isLetter(letter) || letter=='$')){
        throw new IllegalArgumentException ("Invalid discount code");
      }
    }
    return discountCode.toUpperCase();
  }

  public void applyDiscountCode(String discountCode) {
    String normalizedCode = normalizeDiscountCode(discountCode);
    this.discountCode = normalizedCode;
  }
}