如果我在数据库中找不到具有给定id的用户.我想返回一个异常而不是null Dto,我该怎么做?
public UserDto updateUser(Long id, UserDto userDto) {
UserDto userDtoNew = null;
if (userRepository.findById(id).isPresent()) {
User existingUser = userRepository.findById(id).get();
existingUser.setPassword(userDto.getPassword());
existingUser.setUserName(userDto.getUserName());
userDtoNew = userMapper.toDto(existingUser);
return userDtoNew;
}
return userDtoNew;
}