class Nid

class Nid extends NumericArgument {
  
  /**
   * The node storage.
   *
   * @var \Drupal\node\NodeStorageInterface
   */
  protected $nodeStorage;
  
  /**
   * Constructs the Nid object.
   *
   * @param array $configuration
   *   A configuration array containing information about the plugin instance.
   * @param string $plugin_id
   *   The plugin_id for the plugin instance.
   * @param mixed $plugin_definition
   *   The plugin implementation definition.
   * @param \Drupal\node\NodeStorageInterface $node_storage
   *   The node storage handler.
   */
  public function __construct(array $configuration, $plugin_id, $plugin_definition, NodeStorageInterface $node_storage) {
    parent::__construct($configuration, $plugin_id, $plugin_definition);
    $this->nodeStorage = $node_storage;
  }
  
  /**
   * {@inheritdoc}
   */
  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
    return new static($configuration, $plugin_id, $plugin_definition, $container->get('entity_type.manager')
      ->getStorage('node'));
  }
  
  /**
   * Override the behavior of title(). Get the title of the node.
   */
  public function titleQuery() {
    $titles = [];
    $nodes = $this->nodeStorage
      ->loadMultiple($this->value);
    foreach ($nodes as $node) {
      $titles[] = $node->label();
    }
    return $titles;
  }

}