SpringBoot2.2.2 中 jpa Repository的findOne 正确写法 和 findAll

@GetMapping("/user/{id}")
public User getUser(@PathVariable("id") Integer id) {
    User user = new User();
    user.setId(id);
    Example<User> example = Example.of(user);
    Optional<User> one = userRepository.findOne(example);
    return one.get();
}

@GetMapping("/user/all")
public List<User> getAll() {
    List<User> all = userRepository.findAll();
    System.out.println(all);
    return  all;
}