private function registerAppNamespace()
    {
        // get app namespace
        $namespace = $this->applicationConfig->get('Application.Namespace', false);
        if (!$namespace) {
            throw new BootstrapException('Unable to register application namespace. You must define the application namespace in your App.yaml config file.');
        }

        try{
            // register the namespace
            ClassLoader::getInstance()->registerMap([$namespace => $this->applicationAbsolutePath.'App']);
        }catch (\Exception $e){
            throw new BootstrapException('Unable to register application ('.$namespace.' => '.$this->applicationAbsolutePath.'App'.') namespace with ClassLoader.');
        }

    }