validate method

Implementation

@override
void validate(String? newValue) {
  final String? _newValue = newValue;

  if (_newValue == null) {
    if (isRequired) {
      throw InvalidValueException();
    } else {
      return;
    }
  }

  final bool hasMatch = regExp.hasMatch(_newValue);

  if (hasMatch == false) {
    throw InvalidValueException();
  }
}