class CheckExpressionOperandsSizeValidator implements ConstraintValidator<CheckExpressionOperandsSize,
        List<ClientExpression>>, ValidationErrorDescriptorBuilder {

    @Override
    public boolean isValid(List<ClientExpression> value, ConstraintValidatorContext context) {
        return value == null || value.size() >= annotationMin && value.size() <= annotationMax;
    }

}