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Przemyslaw Mazur
Courses Plus Student 9,296 PointsTask one is no longer passing. Please help.
It was fine before and I see no error. What do you think?
public class Order {
private String itemName;
private int priceInCents;
private String discountCode;
private String normalizeDiscountCode(String code) {
for(int i=0; i<code.length();i++) {
char x = code.charAt(i);
if(!(Character.isLetter(x)) || x != '$') {
throw new IllegalArgumentException("Invalid discount code");
}
}
code = code.toUpperCase();
return code;
}
// snip
public void applyDiscountCode(String discountCode) {
this.discountCode = normalizeDiscountCode(discountCode);
}
}
3 Answers
Steve Hunter
57,712 PointsHi there,
Think through your logic. You want to throw the exception if the character is not a letter AND is not a '$'.
Using OR would throw the exception if the character was a '$' as it is not a letter.
I hope that makes sense.
Steve.
Simon Coates
28,694 Pointstry
private String normalizeDiscountCode(String code) {
for(int i=0; i<code.length();i++) {
char x = code.charAt(i);
if(!Character.isLetter(x) && x != '$') {
throw new IllegalArgumentException("Invalid discount code");
}
}
return code.toUpperCase();
}
I think you forgot to apply de morgan's law. If character can be a letter OR '$', then the error condition is when it isn't a character AND isn't '$'.
An alternative is keeping things simple with:
private String normalizeDiscountCode(String code) {
for(char letter: code.toCharArray()) {
if(! (Character.isLetter(letter) || letter == '$')) {
throw new IllegalArgumentException("Invalid discount code");
}
}
return code.toUpperCase();
}
Przemyslaw Mazur
Courses Plus Student 9,296 PointsYup I see now. The hole in my logic is now patched. Thanks guys.
Steve Hunter
57,712 PointsNo problem! 