code: private static void usage() {
      new HelpFormatter().printHelp(String.format(
          "java -cp %s %s -type <[READ, WRITE]> -fileSize <fileSize> -iterations <iterations> "
              + "-concurrency <concurrency>",
          RuntimeConstants.ALLUXIO_JAR, MiniBenchmark.class.getCanonicalName()),
          "run a mini benchmark to write or read a file",
          OPTIONS, "", true);
    }
docs: Prints the usage.