private static Set<String> collectUncheckedNodes(CheckedTreeNode node, Set<String> result) {
    if (node.isChecked()) {
      Enumeration children = node.children();
      while (children.hasMoreElements()) {
        Object child = children.nextElement();
        collectUncheckedNodes((CheckedTreeNode)child, result);
      }
    }
    else {
      result.add(getGroupAndArtifactId(node));
    }
    return result;
  }
private static Set<String> collectUncheckedNodes(CheckedTreeNode node, Set<String> result)