code: public static List<String> getChildrenParentMayNotExist(ZkClient zkClient, String path) {
          try {
              return zkClient.getChildren(path);
          } catch (ZkNoNodeException e) {
              return null;
          }
      }
docs: get children nodes name
  
  @param zkClient zkClient
  @param path     full path
  @return children nodes name or null while path not exist