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[英]Foreign Key constraint violation with bidirectional one-to-one relationship with shared primary key
[英]How do I properly cascade save a one-to-one, bidirectional relationship on primary key in Hibernate 3.6
我與共享密鑰有一對一的雙向實體關系。 當我嘗試保存關聯的所有者時,我得到了一個“null id generated”異常,對照關系的擁有方。 我正在利用hibernate-entitymanager並使用spring進行事務管理。
擁有實體
@Entity
@Table(name = "lead")
public class Lead
{
private Long leadId;
private LeadAffiliate leadAffiliate;
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
public Long getLeadId()
{
return leadId;
}
@OneToOne(cascade = CascadeType.ALL)
@PrimaryKeyJoinColumn
public LeadAffiliate getLeadAffiliate()
{
return leadAffiliate;
}
}
擁有實體
@Entity
@Table(name = "lead_affiliate")
public class LeadAffiliate
{
private Long leadId;
private Lead lead;
@Id
public Long getLeadId()
{
return leadId;
}
@MapsIdmappedBy = "leadAffiliate")
@OneToOne(cascade = CascadeType.All)
@PrimaryKeyJoinColumn
@JoinColumn(name = "lead_id")
public Lead getLead()
{
return lead;
}
}
並且以下代碼用於保存實體:
LeadAffiliate aff = new LeadAffiliate();
aff.setLead(lead);
lead.setLeadAffiliate(aff);
em.persist(lead);
這一切在hibernate 3.5.0-Final中完全正常。 當嘗試升級到3.5.6-Final或3.6.0.Final時,我開始得到“為LeadAffiliate生成的空id”錯誤:
javax.persistence.PersistenceException: org.hibernate.id.IdentifierGenerationException: null id generated for:class com.sellingsource.bizdev.entities.LeadAffiliate
at org.hibernate.ejb.AbstractEntityManagerImpl.convert(AbstractEntityManagerImpl.java:1214)
at org.hibernate.ejb.AbstractEntityManagerImpl.convert(AbstractEntityManagerImpl.java:1147)
at org.hibernate.ejb.AbstractEntityManagerImpl.convert(AbstractEntityManagerImpl.java:1153)
at org.hibernate.ejb.AbstractEntityManagerImpl.persist(AbstractEntityManagerImpl.java:678)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.springframework.orm.jpa.ExtendedEntityManagerCreator$ExtendedEntityManagerInvocationHandler.invoke(ExtendedEntityManagerCreator.java:365)
at $Proxy152.persist(Unknown Source)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.springframework.orm.jpa.SharedEntityManagerCreator$SharedEntityManagerInvocationHandler.invoke(SharedEntityManagerCreator.java:240)
at $Proxy120.persist(Unknown Source)
at com.sellingsource.common.dao.JpaGenericDao.create(JpaGenericDao.java:38)
... 64 more
Caused by: org.hibernate.id.IdentifierGenerationException: null id generated for:class com.sellingsource.bizdev.entities.LeadAffiliate
at org.hibernate.event.def.AbstractSaveEventListener.saveWithGeneratedId(AbstractSaveEventListener.java:123)
at org.hibernate.ejb.event.EJB3PersistEventListener.saveWithGeneratedId(EJB3PersistEventListener.java:69)
at org.hibernate.event.def.DefaultPersistEventListener.entityIsTransient(DefaultPersistEventListener.java:179)
at org.hibernate.event.def.DefaultPersistEventListener.onPersist(DefaultPersistEventListener.java:135)
at org.hibernate.impl.SessionImpl.firePersist(SessionImpl.java:799)
at org.hibernate.impl.SessionImpl.persist(SessionImpl.java:791)
at org.hibernate.engine.EJB3CascadingAction$1.cascade(EJB3CascadingAction.java:48)
at org.hibernate.engine.Cascade.cascadeToOne(Cascade.java:392)
at org.hibernate.engine.Cascade.cascadeAssociation(Cascade.java:335)
at org.hibernate.engine.Cascade.cascadeProperty(Cascade.java:204)
at org.hibernate.engine.Cascade.cascade(Cascade.java:161)
at org.hibernate.event.def.AbstractSaveEventListener.cascadeBeforeSave(AbstractSaveEventListener.java:450)
at org.hibernate.event.def.AbstractSaveEventListener.performSaveOrReplicate(AbstractSaveEventListener.java:282)
at org.hibernate.event.def.AbstractSaveEventListener.performSave(AbstractSaveEventListener.java:203)
at org.hibernate.event.def.AbstractSaveEventListener.saveWithGeneratedId(AbstractSaveEventListener.java:129)
at org.hibernate.ejb.event.EJB3PersistEventListener.saveWithGeneratedId(EJB3PersistEventListener.java:69)
at org.hibernate.event.def.DefaultPersistEventListener.entityIsTransient(DefaultPersistEventListener.java:179)
at org.hibernate.event.def.DefaultPersistEventListener.onPersist(DefaultPersistEventListener.java:135)
at org.hibernate.event.def.DefaultPersistEventListener.onPersist(DefaultPersistEventListener.java:61)
at org.hibernate.impl.SessionImpl.firePersist(SessionImpl.java:808)
at org.hibernate.impl.SessionImpl.persist(SessionImpl.java:782)
at org.hibernate.impl.SessionImpl.persist(SessionImpl.java:786)
at org.hibernate.ejb.AbstractEntityManagerImpl.persist(AbstractEntityManagerImpl.java:672)
... 77 more
順便說一句,我不確定Lead Affiliate的注釋是否適合開始。 他們工作,但似乎有點kludgey。 所以我后來改為:
@Entity
@Table(name = "lead_affiliate")
public class LeadAffiliate
{
private Long leadId;
private Lead lead;
@Id
@GenericGenerator(name = "foreign", strategy = "foreign", parameters = {
@org.hibernate.annotations.Parameter(name = "property", value="lead")
})
@GeneratedValue(generator = "foreign")
public Long getLeadId()
{
return leadId;
}
@OneToOne(mappedBy = "leadAffiliate")
@PrimaryKeyJoinColumn
public Lead getLead()
{
return lead;
}
}
但是,通過這些更改,我得到了相同的結果。 (適用於3.5.0但不適用3.5.6或3.6.0)
有沒有新方法我需要這樣做或這是一個錯誤? 我擔心的是我的代碼目前正在運行,因為有一個bug:/。
規范說派生實體應該是關系的擁有方:
2.4.1對應於派生身份的主鍵
當前實體(“從屬”實體)是多對一或一對一關系的所有者時,實體的身份可以從另一個實體(“父”實體)的身份派生。父實體和外鍵將關系從依賴映射到父。
在您的情況下, LeadAffiliate
是派生的,因此它應該是所有者,當Lead
應該被mappedBy
標記為非擁有方。 以下適用於3.5.0和3.5.6:
public class Lead {
@Id @GeneratedValue
private Long leadId;
@OneToOne(cascade = CascadeType.ALL, mappedBy = "lead")
private LeadAffiliate leadAffiliate;
...
}
。
public class LeadAffiliate {
@Id
private Long leadId;
@OneToOne @MapsId
private Lead lead;
...
}
我的答案不能解釋為什么事情正在使用Hibernate 3.5.0-Final,但不能使用3.5.6-Final或3.6.0.Final(你應該報告這個,我稱之為回歸)。
無論如何,JPA 2.0以標准方式更好地支持派生標識符,在您的情況下,我認為您可以使用Id
注釋簡單地注釋OneToOne
關系。
更新:如axtavt所示,當使用派生標識符時,“依賴”實體必須是關系的所有者。 因此,依賴實體的完整映射將是:
@Entity
@Table(name = "lead_affiliate")
public class LeadAffiliate {
private Lead lead;
@Id
@OneToOne
@JoinColumn(name="FK")
public Lead getLead() {
return lead;
}
}
而“父母”實體:
@Entity
@Table(name = "lead")
public class Lead {
private Long leadId;
private LeadAffiliate leadAffiliate;
@Id @GeneratedValue(strategy = GenerationType.AUTO)
public Long getLeadId() {
return leadId;
}
@OneToOne(cascade = CascadeType.ALL, mappedBy="lead")
public LeadAffiliate getLeadAffiliate() {
return leadAffiliate;
}
}
這是一個有效的JPA 2.0映射, 可與EclipseLink一起使用 。 但是,Hibernate不喜歡它,也不會實例化EntityManagerFactory
(該死!)。
作為解決方法,您將必須使用axtavt建議的解決方案,即聲明主鍵屬性以及關系屬性,並在關系屬性上使用MapsId
。
但上面應該有效,有一個IMO在Hibernate中有一個錯誤(報告為HHH-5695 )。
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