class MenuLinkContentAccessControlHandler

class MenuLinkContentAccessControlHandler extends EntityAccessControlHandler implements EntityHandlerInterface {
  
  /**
   * The access manager to check routes by name.
   *
   * @var \Drupal\Core\Access\AccessManagerInterface
   */
  protected $accessManager;
  
  /**
   * Creates a new MenuLinkContentAccessControlHandler.
   *
   * @param \Drupal\Core\Entity\EntityTypeInterface $entity_type
   *   The entity type definition.
   * @param \Drupal\Core\Access\AccessManagerInterface $access_manager
   *   The access manager to check routes by name.
   */
  public function __construct(EntityTypeInterface $entity_type, AccessManagerInterface $access_manager) {
    parent::__construct($entity_type);
    $this->accessManager = $access_manager;
  }
  
  /**
   * {@inheritdoc}
   */
  public static function createInstance(ContainerInterface $container, EntityTypeInterface $entity_type) {
    return new static($entity_type, $container->get('access_manager'));
  }
  
  /**
   * {@inheritdoc}
   */
  protected function checkAccess(EntityInterface $entity, $operation, AccountInterface $account) {
    switch ($operation) {
      case 'view':
        // There is no direct viewing of a menu link, but still for purposes of
        // content_translation we need a generic way to check access.
        return AccessResult::allowedIfHasPermission($account, 'administer menu');
      case 'update':
        if (!$account->hasPermission('administer menu')) {
          return AccessResult::neutral("The 'administer menu' permission is required.")->cachePerPermissions();
        }
        else {
          // Assume that access is allowed.
          $access = AccessResult::allowed()->cachePerPermissions()
            ->addCacheableDependency($entity);
          /** @var \Drupal\menu_link_content\MenuLinkContentInterface $entity */
          // If the link is routed determine whether the user has access unless
          // they have the 'link to any page' permission.
          if (!$account->hasPermission('link to any page') && ($url_object = $entity->getUrlObject()) && $url_object->isRouted()) {
            $link_access = $this->accessManager
              ->checkNamedRoute($url_object->getRouteName(), $url_object->getRouteParameters(), $account, TRUE);
            $access = $access->andIf($link_access);
          }
          return $access;
        }
      case 'delete':
        return AccessResult::allowedIfHasPermission($account, 'administer menu')->andIf(AccessResult::allowedIf(!$entity->isNew())
          ->addCacheableDependency($entity));
      default:
        return parent::checkAccess($entity, $operation, $account);
    }
  }

}