private static CollectorResult doGetCollectorTree(InternalProfileCollector collector) {
   List<CollectorResult> childResults = new ArrayList<>(collector.children.size());
   for (InternalProfileCollector child : collector.children) {
     CollectorResult result = doGetCollectorTree(child);
     childResults.add(result);
   }
   return new CollectorResult(
       collector.getName(), collector.getReason(), collector.getTime(), childResults);
 }
 public CollectorResult getCollectorTree() {
   return InternalProfileCollector.doGetCollectorTree(this);
 }