我应该在存储库中返回EntityNotFoundException而不是null吗？

Question

以前，我具有以下代码结构：

存储库

public User findByEmail(EmailAddress email);

服务

@Override
public User findByEmail(String email) {
    return userRepository.findByEmail(new EmailAddress(email));
}

@Modifying
@Transactional
@Override
public User add(User user) {
    if (findByEmail(user.getEmail().toString()) == null) {
         // Save the returned id into the entity
         user = userRepository.saveAndFlush(user);
         return user;
    } else {
        throw new EntityAlreadyExistsException();
    }
}

现在我可以具有以下代码结构：

存储库

public Optional<User> findByEmail(EmailAddress email);

服务

@Override
public User findByEmail(String email) {
    Optional<User> user = userRepository.findByEmail(new EmailAddress(email));
    if (user.isPresent()) {
        return user.get();
    } else {
        throw new EntityNotFoundException();
    }
}

@Modifying
@Transactional
@Override
public User add(User user) {
    try  {
        findByEmail(user.getEmail().toString());
        throw new EntityAlreadyExistsException();
    } catch (EntityNotFoundException e) {
        // Save the returned id into the entity
        user = userRepository.saveAndFlush(user);
        return user;
    }
}

我想知道移动到Optional和EntityNotFoundException返回的对象是否有意义吗？

作为一个旁注，为了记录服务使用情况，我还在服务接口中声明了抛出的异常：

public User update(Long id, User user) throws EntityNotFoundException;

这是要做的事吗？