private static List<TreeNode> prepareAccessibleChildren(@Nullable Accessible a) {
      List<TreeNode> result = new ArrayList<>();
      if (a != null) {
        AccessibleContext ac = a.getAccessibleContext();
        if (ac != null) {
          int count = ac.getAccessibleChildrenCount();
          for (int i = 0; i < count; i++) {
            Accessible axComponent = a.getAccessibleContext().getAccessibleChild(i);
            result.add(createAccessibleNode(axComponent));
          }
        }
      }
      return result;
    }
private static List<TreeNode> prepareAccessibleChildren(@Nullable Accessible a)