public function call($class, $method, array $args = array(), $transient = false) {
        $return = null;
        $callback = '';
        if ($transient) {
            $className = $this->loadClass($class, '', false, true);
            if ($className) {
                $callback = array($className, $method);
            }
        } else {
            $className = $this->loadClass($class);
            if ($className) {
                $className = $this->getPlatformClass($className);
                $callback = array($className, $method);
            }
        }
        if (!empty($callback) && is_callable($callback)) {
            try {
                $return = $className::$method(...$args);
            } catch (\Exception $e) {
                $this->log(xPDO::LOG_LEVEL_ERROR, "An exception occurred calling {$className}::{$method}() - " . $e->getMessage());
            }
        } else {
            $this->log(xPDO::LOG_LEVEL_ERROR, "{$class}::{$method}() is not a valid static method.");
        }
        return $return;
    }