public static void updateAll() {
    AnnotationConfiguration config =
                             new AnnotationConfiguration();
    config.addAnnotatedClass(User.class);
    SessionFactory factory;
    factory = config.configure().buildSessionFactory();
    Session session = factory.getCurrentSession();
    session.beginTransaction();

    java.util.List allUsers;
    System.out.println("Updating all records...");
    Query queryResult = session.createQuery("from User");
    allUsers = queryResult.list();
    System.out.println("# of rows:"+allUsers.size());

    for (int i = 0; i < allUsers.size(); i++) {
      User user = (User) allUsers.get(i);
      System.out.println(user);
      user.setPassword("password");
      session.update(user);
    }

    System.out.println("Database table updated...");
    session.getTransaction().commit();
  }