/**
   * A test method to print out the current user's UGI.
   *
   * @param args if there are two arguments, read the user from the keytab and print it out.
   * @throws Exception
   */
  public static void main(String[] args) throws Exception {
    System.out.println("Getting UGI for current user");
    UserGroupInformation ugi = getCurrentUser();
    ugi.print();
    System.out.println("UGI: " + ugi);
    System.out.println("Auth method " + ugi.user.getAuthenticationMethod());
    System.out.println("Keytab " + ugi.isKeytab);
    System.out.println("============================================================");

    if (args.length == 2) {
      System.out.println("Getting UGI from keytab....");
      loginUserFromKeytab(args[0], args[1]);
      getCurrentUser().print();
      System.out.println("Keytab: " + ugi);
      System.out.println("Auth method " + loginUser.user.getAuthenticationMethod());
      System.out.println("Keytab " + loginUser.isKeytab);
    }
  }