class RouteSubscriber

class RouteSubscriber extends RouteSubscriberBase {

  /**
   * The mapper plugin discovery service.
   *
   * @var \Drupal\config_translation\ConfigMapperManagerInterface
   */
  protected $mapperManager;

  /**
   * Constructs a new RouteSubscriber.
   *
   * @param \Drupal\config_translation\ConfigMapperManagerInterface $mapper_manager
   *   The mapper plugin discovery service.
   */
  public function __construct(ConfigMapperManagerInterface $mapper_manager) {
    $this->mapperManager = $mapper_manager;
  }

  /**
   * {@inheritdoc}
   */
  protected function alterRoutes(RouteCollection $collection) {
    $mappers = $this->mapperManager
      ->getMappers($collection);
    foreach ($mappers as $mapper) {
      $collection
        ->add($mapper
        ->getOverviewRouteName(), $mapper
        ->getOverviewRoute());
      $collection
        ->add($mapper
        ->getAddRouteName(), $mapper
        ->getAddRoute());
      $collection
        ->add($mapper
        ->getEditRouteName(), $mapper
        ->getEditRoute());
      $collection
        ->add($mapper
        ->getDeleteRouteName(), $mapper
        ->getDeleteRoute());
    }
  }

  /**
   * {@inheritdoc}
   */
  public static function getSubscribedEvents() : array {

    // Come after field_ui.
    $events[RoutingEvents::ALTER] = [
      'onAlterRoutes',
      -110,
    ];
    return $events;
  }

}