private void updateWatchedTables() throws KeeperException {
    // get the children and watch for new children
    LOG.debug("Updating watches on tables to archive.");
    // get the children and add watches for each of the children
    List<String> tables = ZKUtil.listChildrenAndWatchThem(watcher, archiveHFileZNode);
    LOG.debug("Starting archive for tables:" + tables);
    // if archiving is still enabled
    if (tables != null && tables.size() > 0) {
      getMonitor().setArchiveTables(tables);
    } else {
      LOG.debug("No tables to archive.");
      // only if we currently have a tracker, then clear the archive
      clearTables();
    }
  }
Read the list of children under the archive znode as table names and then sets those tables to
the list of tables that we should archive
@throws KeeperException if there is an unexpected zk exception
hbase-server/src/main/java/org/apache/hadoop/hbase/backup/example/TableHFileArchiveTracker.java