Hibernate多对一将外键更新为空
我正在尝试使我的@OneToMany和@ManyToOne关系正确。
第1类:
@Entitypublic 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....
第2类:
@Entitypublic class Pitch {
@Id
@GeneratedValue
private int id;
@ManyToOne
@JoinColumn(name = "ideaProfileId")
private IdeaProfile ideaProfile;
private Date date;
private String notes;
....getters and setters....
当我加载或保存新记录时,这种关系似乎运行良好:
Hibernate: insert into IdeaProfile (dateConcieved, genreCode, name, statusCode) values (?, ?, ?, ?)Hibernate: insert into Pitch (date, ideaProfileId, notes) values (?, ?, ?)
Hibernate: update Pitch set ideaProfileId=? where id=?
但是,当我尝试更新该记录时,它将尝试将IdeaProfileId设置为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=?
当我调试时,我可以看到IdeaProfileId确实在音高对象上设置了…
仅供参考,我不是直接更新从数据库加载的原始对象。这些域映射到UI更新的Model类。因此,在保存/更新时,我将值映射回新的域对象,包括如下所示的ID:
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();
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?
非常感激。
回答:
您在这里没有双向关联。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,必须始终具有所有者侧和反向侧。反面使用mappingBy属性标记。在OneToMany关联中,反面必须是一侧:
@OneToMany(mappedBy="ideaProfile", fetch=FetchType.EAGER, cascade=CascadeType.ALL)private List<Pitch> pitchs;
…
@ManyToOne@JoinColumn(name = "ideaProfileId")
private IdeaProfile ideaProfile;
以上是 Hibernate多对一将外键更新为空 的全部内容, 来源链接: utcz.com/qa/398554.html