validate method

  1. @override
ValidationException? validate(
  1. Object? value
)
override

Return null if valid, otherwise a ValidationException.

Implementation

@override
ValidationException? validate(Object? value) {
  if (value == null) {
    return ValidationException(this, value);
  }

  if (value is String && value.isNotEmpty) return null;
  if (value is Iterable && value.isNotEmpty) return null;
  if (value is Map && value.isNotEmpty) return null;

  return ValidationException(this, value);
}