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Geocarlos Alves
Geocarlos Alves
13,969 Points


I have used the method 'Character.isJavaIdentifierStart(char)' to pass the exercise in Java Objects / Delivering the MVP / Applying a Discount Code.

In this exercise, you should not allow numbers, however, you must allow '$'. So you cannot use Character.isLetter(char). I passed the exercise with Character.isJavaIdentifierStart(char), but I have wondered if I am supposed to allow ''? That is because if the user happens to use _ in their code, Character.isJavaIdentifierStart('') returns true.

Has anybody used a different method for this, or is this actually the one?