protected function getValidator($data = null)
    {
        if (!$this->validator) {
            if ($data) {
                // Validate without key
                if ($this->lastKey === '') {
                    $data = ['' => $data];
                }

                $this->options['data'] = $data;
            }

            $this->validator = $this->wei->validate($this->options);
        }

        return $this->validator;
    }