code: public static Class<? extends OutputFormat> getNamedOutputFormatClass(
      JobConf conf, String namedOutput) {
      checkNamedOutput(conf, namedOutput, false);
      return conf.getClass(MO_PREFIX + namedOutput + FORMAT, null,
        OutputFormat.class);
    }
docs: Returns the named output OutputFormat.
  
  @param conf        job conf
  @param namedOutput named output
  @return namedOutput OutputFormat