带有注释的 Hibernate 多态集合映射答案

【问题标题】：Hibernate polymorphic collection mapping with annotation带有注释的 Hibernate 多态集合映射
【发布时间】：2014-09-07 06:50:00
【问题描述】：

我为我的客户准备了一个抽象类：

@Entity
public class AbstractClientEntity extends AbstractPersonneEntity implements Demarchable {

@Column(name="ID_REFERENT")
private AbstractEmployeEntity referent;
...

具体类如下所示：

@Entity
@DiscriminatorValue(TypePersonne.Values.INVITE)
public class InviteEntity extends AbstractClientEntity implements Invitable {
...

和

@Entity
@DiscriminatorValue(TypePersonne.Values.AUTRE)
public class AutreClientEntity extends AbstractClientEntity {

我为拥有一组 AbstractClientEntity 的员工提供了另一个抽象类：

@Entity
public class AbstractEmployeEntity extends AbstractPersonneEntity {

@ManyToOne(fetch = FetchType.LAZY)
@JoinColumn(name = "ID_REFERENT", nullable = false)
private MonitriceEntity monitrice = new MonitriceEntity();

@OneToMany(fetch = FetchType.LAZY, mappedBy = "referent")
private Set<AbstractClientEntity> listeClients = new HashSet<AbstractClientEntity>();
...

问题是当我尝试运行我的网络应用程序时，抛出了这个异常：

org.springframework.beans.factory.BeanCreationException: Could not autowire field: private org.hibernate.SessionFactory ch.tupperware.tuppergestion.dao.AbstractDao.sessionFactory; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sessionFactory' defined in ServletContext resource [/WEB-INF/config/tupper-servlet.xml]: Invocation of init method failed; nested exception is org.hibernate.MappingException: Could not determine type for: ch.tupperware.tuppergestion.entity.AbstractEmployeEntity, at table: PERSONNE, for columns: [org.hibernate.mapping.Column(ID_REFERENT)]
    org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:507)
    org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:84)
    org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:283)
    org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1055)
    org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:511)
    org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:450)
    org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:290)
    org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222)
    org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:287)
    org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:189)
    org.springframework.beans.factory.support.DefaultListableBeanFactory.findAutowireCandidates(DefaultListableBeanFactory.java:825)
    org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:767)
    org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:685)

我不知道如何解决这个问题...

感谢您的帮助

【问题讨论】：

标签： java hibernate collections mapping polymorphism

【解决方案1】：

原因很清楚：

Invocation of init method failed; nested exception is org.hibernate.MappingException: Could not determine type for: ch.tupperware.tuppergestion.entity.AbstractEmployeEntity, at table: PERSONNE, for columns: [org.hibernate.mapping.Column(ID_REFERENT)]

您的班级 ch.tupperware.tuppergestion.entity.AbstractEmployeEntity 没有在您的表 PERSONNE 中找到列 ID_REFERENT。

你是如何映射你的AbstractEmployeEntity 类的。如果是抽象类，为什么不用@MappedSuperclass映射呢？

【讨论】：

感谢您的快速回答。我发誓 ID_REFERENT 字段在我的 PERSONNE 表中。我确实用@MappedSuperclass 映射了我的抽象类，因为我希望能够在我的AbstractEmployeEntity 中拥有一个AbstractClientEntity 的集合。当我尝试使用 @MappedSuperclass 注释时，异常 org.hibernate.AnnotationException: Use of @OneToMany 或 @ManyToMany 针对未映射的类：ch.tupperware.tuppergestion.entity.AbstractEmployeEntity.listeClients[ch.tupperware.tuppergestion.entity.AbstractClientEntity ] 被抛出...
我建议你只注释@MappedSuperclass only 抽象类而不是具体类。
我试图用 @MappedSuperClass 注释我的所有抽象类，但现在我有与上述类似的异常，但在一个具体类上：嵌套异常是 org.hibernate.AnnotationException：使用 @OneToMany 或 @针对未映射类的多对多：ch.tupperware.tuppergestion.entity.AmbassadriceEntity.listeClients[ch.tupperware.tuppergestion.entity.AbstractClientEntity]

【解决方案2】：

最后，我会回答我自己的问题，希望它对某人有所帮助......

经过多次尝试，我采用了一个解决方案，为我必须在我的 AbstractEmployeEntity 中管理的每个具体类创建一个列表：

@Entity
public class AbstractEmployeEntity extends AbstractPersonneEntity {

@OneToMany(fetch = FetchType.LAZY, mappedBy = "referent")
private Set<HotesseEntity> listeHotesse = new HashSet<HotesseEntity>();

@OneToMany(fetch = FetchType.LAZY, mappedBy = "referent")
private Set<InviteEntity> listeInvites = new HashSet<InviteEntity>();

@OneToMany(fetch = FetchType.LAZY, mappedBy = "referent")
private Set<AutreClientEntity> listeAutreClients = new HashSet<AutreClientEntity>();

希望这会对某人有所帮助...

【讨论】：