如何在JavaFX中获得父节点中的所有节点？

public static ArrayList<Node> getAllNodes(Parent root) {    ArrayList<Node> nodes = new ArrayList<Node>();    addAllDescendents(root, nodes);    return nodes;}private static void addAllDescendents(Parent parent, ArrayList<Node> nodes) {    for (Node node : parent.getChildrenUnmodifiable()) {        nodes.add(node);        if (node instanceof Parent) addAllDescendents((Parent)node, nodes);    }}