休眠多对一更新外键为空 [英] Hibernate Many to one updating foreign key to null

问题描述

我试图让我的@OneToMany和@ManyToOne关系正确。

1级：

 @Entity 
 public class IdeaProfile {
 
 @Id 
 @GeneratedValue 
 private int ideaProfileId; 
 
私人字符串名称; 
 
日期dateConcieved; 
 
 @OneToOne 
 @JoinColumn（name =statusCode）
私人状态状态; 
 
 $ b @OneToMany（fetch = FetchType.EAGER，targetEntity = Pitch.class，cascade = CascadeType.ALL）
 @JoinColumn（name =ideaProfileId）
私人列表< Pitch> pitchs; 
 
 .... getters and setters .... 
  

Class2：

  @Entity 
公共班级Pitch {
 
 @Id 
 @GeneratedValue 
 private int id; 
 
 @ManyToOne 
 @JoinColumn（name =ideaProfileId）
私人IdeaProfile ideaProfile; 
 
私人日期日期; 
 
私人字符串笔记; 
 
 .... getters and setters .... 
  

这种关系在加载或保存新记录时似乎工作正常：
$ b $ pre $ Hibernate：插入到IdeaProfile（dateConcieved，genreCode，name， Hibernate：插入Pitch（date，ideaProfileId，notes）值（？，？，？）
Hibernate：更新Pitch set ideaProfileId =？其中id =？


但是，当我尝试更新该记录时，它会尝试将IdeaProfileId设置为null：

  Hibernate：更新IdeaProfile set dateConcieved = ?, genreCode = ?, name =？，statusCode = ?,其中ideaProfileId =？ 
 Hibernate：更新音高设置日期=？，ideaProfileId =？，音符=？其中id =？ 
 Hibernate：更新Pitch set ideaProfileId = null其中ideaProfileId =？ 
  

当我调试时，我可以看到IdeaProfileId确实设置在Pitch Object上...

仅供参考，我不直接更新从数据库加载的原始对象。这些域被映射到UI更新的Model类。所以在保存/更新时，我会将这些值映射回新的域对象，包括如下的ID：

  IdeaProfile domain = new IdeaProfile（）; 
 domain.setId（model.getIdeaProfileId（））; 
 domain.setName（model.getName（））; 
 domain.setStatus（model.getStatus（））; 
 domain.setDateConcieved（Date.valueOf（model.getDateConvieved（）））; （PitchModel pitch：model.getPitches（））{
 Pitch pitchDomain = new Pitch（）; 
 pitchDomain.setId（pitch.getId（））; 
 pitchDomain.setDate（Date.valueOf（pitch.getDate（）））; 
 pitchDomain.setNotes（pitch.getNotes（））; 
 pitchDomain.setIdeaProfile（domain）; 
 if（domain.getPitchs（）== null）{
 domain.setPitchs（new ArrayList< Pitch>（））; 
} 
 domain.getPitchs（）。add（pitchDomain）; 
} 
 
 openSession（）; 
 session.beginTransaction（）; 
 session.saveOrUpdate（domain）; 
 session.getTransaction（）。commit（）; 
 closeSession（）; 
  

有谁知道我做错了什么，所以Hibernate导致更新尝试将IdeaProfileId设置为null？

非常感谢。

解决方案

您没有双向协会在这里。您有两个独立的关联，每个关联都错误地映射到同一列。

在双向关联中，您必须始终拥有所有者方和反方。反面是使用mappedBy属性标记的。在OneToMany关联中，反面必须是单面：

  @OneToMany（mappedBy =ideaProfile，fetch = FetchType.EAGER，cascade = CascadeType.ALL）
 private List< Pitch> pitchs; 
  

...

  @ManyToOne 
 @JoinColumn（name =ideaProfileId）
私人IdeaProfile ideaProfile; 
  

I am trying to get my @OneToMany and @ManyToOne relationships correct.

Class 1:

@Entity
public class IdeaProfile {

@Id
@GeneratedValue
private int ideaProfileId;

private String name;

Date dateConcieved;

@OneToOne
@JoinColumn(name="statusCode")  
private Status status;


@OneToMany(fetch=FetchType.EAGER, targetEntity=Pitch.class, cascade=CascadeType.ALL)
@JoinColumn(name = "ideaProfileId") 
private List<Pitch> pitchs;

    ....getters and setters....

Class2:

@Entity
public class Pitch {

@Id
@GeneratedValue
private int id;

@ManyToOne
@JoinColumn(name = "ideaProfileId")
private IdeaProfile ideaProfile;

private Date date;

private String notes;

 ....getters and setters....

This relationship seems to work fine when I am loading or saving a new record:

Hibernate: insert into IdeaProfile (dateConcieved, genreCode, name, statusCode) values (?, ?, ?, ?)
Hibernate: insert into Pitch (date, ideaProfileId, notes) values (?, ?, ?)
Hibernate: update Pitch set ideaProfileId=? where id=?

However, when I try to update that record, it tries to set the IdeaProfileId to null:

Hibernate: update IdeaProfile set dateConcieved=?, genreCode=?, name=?, statusCode=?,  where ideaProfileId=?
Hibernate: update Pitch set date=?, ideaProfileId=?, notes=? where id=?
Hibernate: update Pitch set ideaProfileId=null where ideaProfileId=?

When I debug I can see that IdeaProfileId is indeed set on Pitch Object...

FYI, I am not directly updating the original objects that I loaded from the DB. These domains get mapped to a Model class which is what the UI updates. So on save/update I map the values back to new domain objects, including the IDs like the following:

IdeaProfile domain = new IdeaProfile();
domain.setId(model.getIdeaProfileId());
domain.setName(model.getName());
domain.setStatus(model.getStatus());
domain.setDateConcieved(Date.valueOf(model.getDateConvieved()));
for (PitchModel pitch : model.getPitches()) {
     Pitch pitchDomain = new Pitch();
     pitchDomain.setId(pitch.getId());
     pitchDomain.setDate(Date.valueOf(pitch.getDate()));
     pitchDomain.setNotes(pitch.getNotes());
     pitchDomain.setIdeaProfile(domain);
     if(domain.getPitchs() == null ) {
        domain.setPitchs(new ArrayList<Pitch>());
     }
     domain.getPitchs().add(pitchDomain);
 }

openSession();
session.beginTransaction();
session.saveOrUpdate(domain);
session.getTransaction().commit();
closeSession();

Does anyone know what I have done wrong so Hibernate causes the update to try to set IdeaProfileId to null?

Much appreciated.

解决方案

You don't have a bidirectional association here. You have two independent associations, each incorrectly mapped to the same column.

In a bidirectional association, you must always have an owner side, and an inverse side. The inverse side is marked using the mappedBy attribute. In a OneToMany association, the inverse side must be the one-side:

@OneToMany(mappedBy="ideaProfile", fetch=FetchType.EAGER, cascade=CascadeType.ALL)
private List<Pitch> pitchs;

...

@ManyToOne
@JoinColumn(name = "ideaProfileId")
private IdeaProfile ideaProfile;

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