Question

我有这个型号：

@Entity
@Table(name = "candidate")
@XmlRootElement(name = "candidate")
public class Candidate{
@ManyToMany(mappedBy = "candidates", fetch = FetchType.EAGER)
    @XmlTransient
    public Set<Vacancy> getVacancies() {
        return vacancies;
    }
....
}

和后映射：

@Entity
@Table(name = "vacancy")
@XmlRootElement(name="vacancy")
public class Vacancy {@ManyToMany( fetch = FetchType.EAGER)
    @JoinTable(name = "vacancy_candidate", joinColumns = @JoinColumn(name = "vacancy_id"), inverseJoinColumns = @JoinColumn(name = "candidate_id"))
    public Set<Candidate> getCandidates() {
        return candidates;
    }
    ...
}

我有控制器方法：

@RequestMapping("/saveCandidate")
public String saveCandidate(
        Model model,
        @ModelAttribute("candidateFromRequest") Candidate candidateFromRequest,

        @ModelAttribute("vacanciesForCandidate") Set<Vacancy> vacanciesForCandidate,

        RedirectAttributes redirectAttributes) {

    candidateService.updateCandidateAndLinkedEntities(candidateFromRequest,
            vacanciesForCandidate,...);
    ...
}

下一级：

    @Transactional
    @Service("candidateService")
    public class CandidateService {
    public void updateCandidateAndLinkedEntities(Candidate candidate,
                Set<Vacancy> vacancies, ...) {

            if (candidate == null)
                throw new NullPointerException("null candidate entity");


            if (vacancies != null) {

                candidate.setVacancies(vacancies);

                for (Vacancy vacancy : vacancies) {
                    vacancy.getCandidates().add(candidate);
                    vacancyDao.update(vacancy);
                }
            }
            candidateDao.update(candidate);//here all right, how I wish(I am about state of candidate entity)

        }
        ...
    }

更新方法实现：

空缺：

@Override
    public boolean update(Vacancy vacancy) throws HibernateException {
        Session session = sessionFactory.getCurrentSession();
        if (vacancy == null) {
            return false;
        }
        session.update(vacancy);
        return true;

    }

候选：

@Override
    public boolean update(Candidate candidate) throws HibernateException{
        Session session = sessionFactory.getCurrentSession();
        if (candidate == null) {
            return false;
        }
        session.update(candidate);

        return true;

    }

我的行为很奇怪。如果我给候选人增加新的空缺 - 它运作良好。但如果我删除空缺 - 它不起作用。

我不理解。

Answer 1

当你从候选人名单中删除空缺时，不要忘记从候选人名单中删除候选人，反之亦然。还要记住：如果你的系统中某处有某个地方，以后发送已经删除的空缺（反之亦然），该实体将再次被保留。

多对多的联想。数据不会删除

1 个答案: