code: private static void setMetaStoreURI(
        Configuration conf, Map<String, String> match) {
      try {
        // If the host is set, construct a new MetaStore URI and set the property
        // in the Configuration. Otherwise, do not change the MetaStore URI.
        String host = match.get(URIPattern.HOST);
        if (host != null && !NOT_SET.equals(host)) {
          int port;
          try {
            port = Integer.parseInt(match.get(URIPattern.PORT));
          } catch (NumberFormatException e) {
            port = UNSPECIFIED_PORT;
          }
          conf.set(HIVE_METASTORE_URI_PROP,
              new URI("thrift", null, host, port, null, null, null).toString());
        }
      } catch (URISyntaxException ex) {
        throw new DatasetOperationException(
            "Could not build metastore URI", ex);
      }
    }
docs: Sets the MetaStore URI in the given Configuration, if there is a host in
  the match arguments. If there is no host, then the conf is not changed.
  
  @param conf a Configuration that will be used to connect to the MetaStore
  @param match URIPattern match results