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Java Java Objects Delivering the MVP Applying a Discount Code

Holly Bancroft
Holly Bancroft
5,150 Points

Help with the code challenge

Any suggestions? It needs to check that the string only contains letters or the symbol "$". Checking for the symbol "$" is where I'm having trouble. Keep getting syntax or runtime errors with all the ideas I've had.

'''java public void applyDiscountCode(String discountCode) { this.discountCode = normalizeDiscountCode(discountCode);

}

private String normalizeDiscountCode(String discountCode) {

for(int i = 0; i < discountCode.length(); i++){
if(!Character.isLetter(discountCode.charAt(i)) && discountCode.charAt(i) != ("$") ) {
  throw new IllegalArgumentException("Invalid discount code");
  }    
}

return discountCode.toUpperCase();

} '''

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 = normalizeDiscountCode(discountCode);

  }

  private String normalizeDiscountCode(String discountCode) {

    for(int i = 0; i < discountCode.length(); i++){
    if(!Character.isLetter(discountCode.charAt(i)) && discountCode.charAt(i) != ("$") ) {
      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

Saai Shree Rama Sarikonda
Saai Shree Rama Sarikonda
1,481 Points

This would solve the problem

    for(int i = 0; i < discountCode.length(); i++){
        if( !Character.isLetter(discountCode.charAt(i)) && discountCode.charAt(i) != '$' ) {
            throw new IllegalArgumentException("Invalid discount code");
        }    
    }