code: public static boolean isMultiNamedOutput(JobConf conf, String namedOutput) {
      checkNamedOutput(conf, namedOutput, false);
      return conf.getBoolean(MO_PREFIX + namedOutput + MULTI, false);
    }
docs: Returns if a named output is multiple.
  
  @param conf        job conf
  @param namedOutput named output
  @return <code>true</code> if the name output is multi, <code>false</code>
  if it is single. If the name output is not defined it returns
  <code>false</code>