code: public static void main(String[] args) throws IOException {
      if (args.length != 1) {
        System.err.println("Usage: JenkinsHash filename");
        System.exit(-1);
      }
      FileInputStream in = new FileInputStream(args[0]);
      byte[] bytes = new byte[512];
      int value = 0;
      JenkinsHash hash = new JenkinsHash();
      for (int length = in.read(bytes); length > 0 ; length = in.read(bytes)) {
        value = hash.hash(bytes, length, value);
      }
      System.out.println(Math.abs(value));
    }
docs: Compute the hash of the specified file
  @param args name of file to compute hash of.
  @throws IOException