Symfony 3登录侦听器中的用户存储库

我愿意构建登录名的听众，更新登录计数，并在用户成功登录时更新登录日期到数据库。

我成功地获得了用户详细信息，但无法访问它们，也无法更新数据库

src/appbundle/listerer/securityListener.php：

namespace AppBundleListener;
use SymfonyComponentSecurityHttpEventInteractiveLoginEvent;
use SymfonyComponentSecurityCoreAuthenticationTokenStorageTokenStorage;
#use DoctrineBundleDoctrineBundleRegistry as Doctrine;
use DoctrineORMEntityManager;
class SecurityListener
{
    private $tokenStorage;
    public function __construct(TokenStorage $tokenStorage, EntityManager $doctrine)
    {
    }
    public function onSecurityInteractiveLogin(InteractiveLoginEvent $event)
    {
    if ( $event->getAuthenticationToken()->isAuthenticated() ) {
        $user = $event->getAuthenticationToken()->getUser();
            var_dump($user->id);
    }
    /**
     * Update lastLogin and loginCount for user in database
     */
    $em = $this->getDoctrine()->getManager();
        $user = $em->getRepository('AppBundle:User')->find($user->id);
        if( !$user )
        {
            throw $this->createNotFoundException(
                'User could not be found for id '. $user->id
            );
        }
        $user->setLastLogin(date());
        $user->setLoginCount($user->loginCount +1);
        $em->flush;

    }
}

错误：

Error: Cannot access private property AppBundleEntityUser::$id