protected function initAppSystem(string $name, string $className)
    {
        if (!class_exists($className)) {
            throw new Exception(
                'The appSystem class '.$className.' not exist.',
                self::ERR_APP_SYSTEM_CLASS_NOT_EXIST
            );
        }
        
        $appSystem = new $className;
        if ($appSystem instanceof SystemInterface === false) {
            throw new Exception(
                'The appSystem '.$className.' not implement the interface.',
                self::ERR_APP_SYSTEM_NOT_IMPLEMENT_INTERFACE
            );
        }
        
        $this->appSystemList[$name] = $appSystem;
        
        if ($appSystem->toRun() === true) {
            $this->runTasks->addToRunSteps(
                $name,
                \BFW\RunTasks::generateStepItem(null, [$appSystem, 'run'])
            );
        }
    }