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Start your free trialTalal Alghamdi
1,603 PointsHow to verify a specific character?
I verified the letters, but couldn't figure out how to verify the $ character.
public class Order {
private String itemName;
private int priceInCents;
private String discountCode;
public Order(String itemName, int priceInCents) {
this.itemName = itemName;
this.priceInCents = priceInCents;
}
private String normalizeDiscountCode (String code, char ignore) {
for (char ch: code.toCharArray()){
if ((ch >= 'a' && ch <= 'z') || (ch >= 'A' && ch <= 'Z')) {
discountCode= code.toUpperCase();
}
else {
throw new IllegalArgumentException("Invalid discoubt code");
}
}
return discountCode;
}
public String getItemName() {
return itemName;
}
public int getPriceInCents() {
return priceInCents;
}
public String getDiscountCode() {
return discountCode;
}
public void applyDiscountCode(String discountCode) {
this.discountCode = normalizeDiscountCode(discountCode);
}
}
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
28,558 PointsYou might have been overthinking the solution a bit, the answer is actually very simple. To check that the character is equal to $ you can simply use a normal equal comparison ch == '$'
. If you add it together with another || like this:
if ((ch >= 'a' && ch <= 'z') || (ch >= 'A' && ch <= 'Z') || ch == '$') {
discountCode= code.toUpperCase();
}
Then your if statement will be correct.
Though I see that you have added an ignore
parameter to your normalizeDiscountCode
method. You have to remove that in order to complete the challenge, since that is not meant to be there.
It is also worth mentioning that while the above if statement works it can be greatly simplified using a method on the Character
class called isLetter
. As the name implies isLetter
checks if the argument provided is a letter or not. By using that in place of the comparisons you wrote before you get this:
if (Character.isLetter(ch) || ch == '$') {
discountCode= code.toUpperCase();
}
Which is easier to read and performs the same task.