public List<QueryInfo> getHistoricalQueryInfos() {
    List<QueryInfo> result = new LinkedList<>();
    synchronized (webuiLock) {
      if (historicalQueryInfos != null) {
        result.addAll(historicalQueryInfos.values());
        Collections.reverse(result);
      }
    }
    return result;
  }
@return displays representing a number of historical SQLOperations, at max number of
hive.server2.webui.max.historic.queries. Newest items will be first.
service/src/java/org/apache/hive/service/cli/operation/QueryInfoCache.java