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Start your free trialisaiah yarborough
7,260 PointsI don't know whats wrong?
I just need help here to see where I'm going wrong
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 (char letter: discountCode.toCharArray()) {
if ( ! Character.isLetter(letter) && letter != '$') {
throw new IllegalArgumentException("Invalid discount code.");
}
}
return discountCode.toUpperCase();
}
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(); // $ALE
try {
// This will throw an exception because it contains numbers
order.applyDiscountCode("ABC123");
} catch (IllegalArgumentException iae) {
System.out.println(iae.getMessage()); // Prints "Invalid discount code"
}
try {
// This will throw as well, because it contains a symbol.
order.applyDiscountCode("w@w");
}catch (IllegalArgumentException iae) {
System.out.println(iae.getMessage()); // Prints "Invalid discount code"
}
}
}
1 Answer
Steve Hunter
57,712 PointsHiya,
Follow your logic. Use the character '$'.
Character.isLetter('$') == false - which gets negated to true '$' != '$' == false - which gets negated to true
true && true = true, so the exception gets thrown. Bad.
Use 'A'
Character.isLetter('A') == true which gets negated to false 'A' != '$' == true which gets negated to false.
false && false == false - no exception thrown; good!
Use '5';
Character.isLetter('5') == false negated to true '5' != '$' == true - negated to false
true && false = false - no exception thrown. Bad.
If one side evaluates to true, you want the exception throwing. That's not an && relationship.
Steve.
isaiah yarborough
7,260 Pointsisaiah yarborough
7,260 PointsThanks I got it now