public function behaviorValidator($attribute, $params)
    {
        $behavior = $params['behavior'];
        $validator = $params['validator'];
        unset($params['behavior']);
        unset($params['validator']);
        if (($behavior = $this->getBehavior($behavior)) !== null) {
            return $behavior->{$validator}($attribute, $params);
        }

        return true;
    }