@Override
  public void configure(MapredContext context) {
    if (context != null) {
      if(HiveConf.getBoolVar(context.getJobConf(), HiveConf.ConfVars.HIVE_USE_GOOGLE_REGEX_ENGINE)){
        this.useGoogleRegexEngine=true;
      }
    }

  }
UDF to extract a specific group identified by a java regex. Note that if a
regexp has a backslash ('\'), then need to specify '\\' For example,
regexp_extract('100-200', '(\\d+)-(\\d+)', 1) will return '100'
ql/src/java/org/apache/hadoop/hive/ql/udf/generic/GenericUDFRegExp.java