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Start your free trialAmir Tamim
8,597 PointsPlease help! Been stuck all day
I have to say I kinda give up on this one. Can someone please give the logic behind the answer to this and correct my errors?
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){
if(discountCode.indexOf(discountCode)!=-1){
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(); // $ALE
try {
// This will throw an exception because it contains numbers
order.applyDiscountCode("ABC123");
} catch (IllegalArgumentException iae) {
System.out.println(iae.getMessage()); // Prints "Invalid discount code"
}
try {
// This will throw as well, because it contains a symbol.
order.applyDiscountCode("w@w");
}catch (IllegalArgumentException iae) {
System.out.println(iae.getMessage()); // Prints "Invalid discount code"
}
}
}
2 Answers
Felix Sonnenholzer
14,654 PointsHi there,
You have to check every char
in that String.
So you would have to loop over every char to check.
private String normalizeDiscountCode(String discountCode) {
for (char c : discountCode.toCharArray()) {
if ( !(Character.isLetter(c) || c == '$')) {
throw new IllegalArgumentException("Invalid discount code");
}
}
return discountCode.toUpperCase();
}
Just for explanation if
- c is a letter it returns
true
-> thanks to ! it will befalse
and won't throw an Exception - c is not a letter -> check if c is a $
- c is a $ it returns
true
-> thanks to ! it will befalse
and won't throw an Exception - c is not $ it returns
false
-> thanks to ! it will betrue
and will throw an Exception
- c is a $ it returns
I hope I expressed it easy to understand.
Have fun
Christopher Ekeren
1,370 PointsThank you for this! I was struggling mightily on this. I actually started using the toCharArray approach but figured I was just overcomplicating it. Apparently I was on the right track, I should have just stuck with it lol.
Amir Tamim
8,597 PointsAmir Tamim
8,597 PointsQUESTION IS:
In the normalizeDiscountCode verify that only letters or the $ character are used. If any other character is used, throw a IllegalArgumentException with the message Invalid discount code.