code: static void createIfNotThere(ZooKeeper zookeeper, String znode) throws KeeperException, InterruptedException {
          try {
              create(zookeeper, znode);
          } catch (KeeperException e) {
              if (e.code() != KeeperException.Code.NODEEXISTS) {
                  // Rethrow all exceptions, except "node exists",
                  // because if the node exists, this method reached its goal.
                  throw e;
              }
          }
      }
docs: Create an empty normal (persistent) Znode. If the znode already exists, do nothing.
  
  @param zookeeper ZooKeeper instance to work with.
  @param znode     Znode to create.
  @throws KeeperException
  @throws InterruptedException