protected void cacheDescendantsHelper(Node n) {
for (Node child : n.getChildNodes()) {
if (descendants.contains(child)) {
continue;
}
descendants.add(child);
cacheDescendantsHelper(child);
}
}
protected boolean isAncestorHelper(List<Node> children, Node node, Set<Node> seenNodes) {
for (Node n : children) {
if (seenNodes.contains(n)) {
continue;
}
seenNodes.add(n);
if (n.equals(node)) {
return true;
}
if (isAncestorHelper(n.getChildNodes(), node, seenNodes)) {
return true;
}
}
return false;
}