@Override
      protected void doExec(ZooKeeper zk) {
        zk.getChildren(path, false, (rc, path, ctx, children) -> onComplete(zk, rc, children, true),
          null);
      }
A very simple read only zookeeper implementation without watcher support.
hbase-client/src/main/java/org/apache/hadoop/hbase/zookeeper/ReadOnlyZKClient.java