public String getUser() throws IOException {
    try {
      UserGroupInformation ugi = Utils.getUGI();
      return ugi.getUserName();
    } catch (LoginException le) {
      throw new IOException(le);
    }
  }
@return the user name set in hadoop.job.ugi param or the current user from System
@throws IOException
common/src/java/org/apache/hadoop/hive/conf/HiveConf.java