JPA如何避免更新@ManyToOne或@OneToOne中的关联实体

Question

I have two entities like this:

@Entity
@Table(name = "article")
@EntityListeners({AuditingEntityListener.class})
public class Notification implements Serializable {

    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Id
    private Integer id;

    @OneToMany(mappedBy = "notification", cascade = {CascadeType.PERSIST})
    private List<NotificationLang> langs;

    @OneToMany(mappedBy = "notification", cascade = {CascadeType.PERSIST})
    private List<NotificationTarget> targets;

    @LastModifiedDate
    @Temporal(TemporalType.TIMESTAMP)
    @Column(name = "updated_at")
    private Date updatedAt;

    @CreatedDate
    @Temporal(TemporalType.TIMESTAMP)
    @Column(name = "created_at")
    private Date createdAt;

}


@Entity
@Table(name = "article_count")
@EntityListeners({AuditingEntityListener.class})
public class NotificationTarget implements Serializable {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @JsonIgnore
    private Integer id;

    @Column(name = "user_id")
    private String userId;

    @ManyToOne(optional = false)
    @JoinColumn(name = "notification_id")
    private Notification notification;
}

Notification and NotificationTarget are associated, If I update NotificationTarget :

NotificationTarget notificationTarget = notificationTargetRepository.findByNotificationIdAndUserId(
        notificationId, userId);
notificationTarget.setUserId(userId);
notificationTargetRepository.save(notificationTarget);

hibernate will update Notification too. I have checked update Notification because Notification has EntityListener, AuditingEntityListener will change updatedAt field when DefaultFlushEntityEventListener invoke Interceptor. But in this business case, I don't want to change Notification when updating NotificationTarget, is there some advice?

Sorry, I think the problem describe is wrong.

I debugged and found that update both because of NotificationLang list is check as dirty in CollectionType.isEqual . But I don't know why it is dirty??

Answer 1

您可以在NotificationTarget的映射注释中添加insertable = false, updatable = false属性。

Answer 2

You have added cascade = {CascadeType.PERSIST} to targets in Notification class, this will propagate persistence operations to all the related entity managers.

Just remove it.