code: void ensureRequiredZnodesExist(ZooKeeper zookeeper, String znode) throws KeeperException, InterruptedException {
          mkdirp(zookeeper, znode);
          createIfNotThere(zookeeper, QUEUE_NODE);
          createIfNotThere(zookeeper, POOL_NODE);
      }
docs: Make sure the required znodes are present on the quorum.
  
  @param zookeeper ZooKeeper connection to use.
  @param znode Base-path for our znodes.