java - 如何从可选 ifPresentOrElse 返回方法值

Question

我有一个编译错误，因为 findByUserIdAndVoteDate 返回 void （不是 VoteResponseDTO ）， voteRepository.save() - 返回我需要的值，我怎样才能得到它？

    public VoteResponseDTO addVote(User user, VoteCreationDTO voteCreationDTO) {  
   VoteResponseDTO createdVote = voteRepository.findByUserIdAndVoteDate(user.getId(), LocalDate.now(clock))
                .ifPresentOrElse(oldVote -> {
                            var vote = new Vote(user, restaurant);
                            vote.setId(oldVote.getId());
                            voteRepository.save(vote);
                        },
                        () -> voteRepository.save(new Vote(user, restaurant)));
        }

标签： java

Answer 1

感谢@Michael，它有效。

VoteResponseDTO voteResponse = toVoteResponseDTO(voteRepository.findByUserIdAndVoteDate(user.getId(), LocalDate.now(clock))
                .map(oldVote -> {
                    var vote = new Vote(user, restaurant);
                    vote.setId(oldVote.getId());
                    return voteRepository.save(vote);
                }).orElseGet(
                        () -> voteRepository.save(new Vote(user, restaurant))));