JPA没有将外键保存到@OneToMany关系

Question

我将Spring和Hibernate用作JPA提供程序，并尝试获取@OneToMany（具有许多电话号码的联系人）以将外键保存在电话号码表中。从我的表单中，我得到一个Contact对象，其中有一个Phone（数字）列表。Contact可以正确持久保存（Hibernate从指定序列中获取PK）。电话（号码）列表也将保留正确的PK，但“联系人”表中没有FK。

public class Contact implements Serializable {

    @OneToMany(mappedBy = "contactId", cascade = CascadeType.ALL, fetch=FetchType.EAGER)
    private List<Phone> phoneList;

}

public class Phone implements Serializable {

    @JoinColumn(name = "contact_id", referencedColumnName = "contact_id")
    @ManyToOne
    private Contact contactId;

}

@Repository("contactDao")
@Transactional(readOnly = true)
public class ContactDaoImpl implements ContactDao {

    @Transactional(readOnly = false, propagation = Propagation.REQUIRES_NEW)
    public void save(Contact c) {
        em.persist(c);
        em.flush();
    }
}


@Controller
public class ContactController {
    @RequestMapping(value = "/contact/new", method = RequestMethod.POST)
    public ModelAndView newContact(Contact c) {
        ModelAndView mv = new ModelAndView("contactForm");
        contactDao.save(c);
        mv.addObject("contact", c);
        return mv;
    }
}

希望我掌握了以上所有相关内容，否则请通知我。

Answer 1

您必须自己管理Java关系。对于这种事情，您需要类似：

@Entity
public class Contact {
  @Id
  private Long id;

  @OneToMany(cascade = CascadeType.PERSIST, mappedBy = "contact")
  private List<Phone> phoneNumbers;

  public void addPhone(PhoneNumber phone) {
     if (phone != null) {
        if (phoneNumbers == null) {
            phoneNumbers = new ArrayList<Phone>();          
        }
        phoneNumbers.add(phone);
        phone.setContact(this);
     }
  }

  ...
}

@Entity
public class Phone {
  @Id
  private Long id;

  @ManyToOne
  private Contact contact;

  ...
}