public function call($params = null)
    {
        $method = $this->method;

        if (!empty($this->constructor_arguments)) {
            $instance = new $this->class($this->constructor_arguments);
        } else {
            $instance = new $this->class();
        }
        if (!is_null($params)) {
            return $instance->$method($params);
        }
        return $instance->$method();
    }