必须加@Transactional事务注解才能成功插入数据，原因未知。

项目名：patentFlowManagementProject

如果不加事务注解，数据插入失败而且无任何报错，很诡异。

    @Override
    @Transactional
    public void joinPrefecture(String prefectureId, String userId) throws Exception {
        Prefecture prefecture = findById(Prefecture.class, prefectureId);
        Applicant applicant = findById(Applicant.class, userId);
        PrefectureApplicant prefectureApplicant = new PrefectureApplicant();
        prefectureApplicant.setId(UUIDGenerator.randomUUID());
        prefectureApplicant.setType("applying");
        prefectureApplicant.setPrefecture(prefecture);
        prefectureApplicant.setApplicant(applicant);
        SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        prefectureApplicant.setTime(simpleDateFormat.format(new Date(System.currentTimeMillis())));
        System.out.println(prefectureApplicant.toString());
        System.out.println(prefectureApplicant.getId());
        System.out.println(prefectureApplicant.getTime());
        System.out.println(prefectureApplicant.getType());
        save(prefectureApplicant);
    }