class MotanDemoServiceImpl implements MotanDemoService {

    @Override
    public String hello(String name) {
        System.out.println(name);
        return "Hello " + name + "!";
    }

    @Override
    public User rename(User user, String name) throws Exception {<FILL_FUNCTION_BODY>}

}

        Objects.requireNonNull(user);
        System.out.println(user.getId() + " rename " + user.getName() + " to " + name);
        user.setName(name);
        return user;
    
<no_super_class>