Java JPA/Hibernate 嵌入式 ID

JPA/Hibernate Embedded id

提问by RoD

I would like to do something like that:

我想做这样的事情：

• An object ReportingFile that can be a LogRequest or a LogReport file. ( both got the same structure)
• An object Reporting containing for one logRequest, a list of logReport with a date.

• 对象 ReportingFile 可以是 LogRequest 或 LogReport 文件。（两者的结构相同）
• 一个对象 Reporting 包含一个 logRequest，一个带有日期的 logReport 列表。

I tryed to set an EmbededId, that would be an attribute of the logRequest. And that's the problem i got. I don't arrive to mannage embedded id. ( http://docs.jboss.org/hibernate/stable/annotations/reference/en/html_single/#entity-mapping-identifier)

我试图设置一个 EmbededId，这将是 logRequest 的一个属性。这就是我遇到的问题。我不是来管理嵌入式 ID 的。（http://docs.jboss.org/hibernate/stable/annotations/reference/en/html_single/#entity-mapping-identifier）

If you have a clue on how i should do it :)

如果你知道我应该怎么做：)

An example (not working) would be:

一个例子（不工作）是：

@Entity
@AssociationOverride( name="logRequest.fileName", joinColumns = { @JoinColumn(name="log_request_file_name") } )
public class Reporting {

    @EmbeddedId
    private ReportingFile logRequest;

    @CollectionOfElements(fetch = FetchType.EAGER)
    @JoinTable(name = "t_reports", schema="", joinColumns = {@JoinColumn(name = "log_report")})
    @Fetch(FetchMode.SELECT)
    private List<ReportingFile> reports;

    @Column(name="generated_date",nullable=true)
    private Date generatedDate;

    [...]
}

@Embeddable
public class ReportingFile {

    @Column(name="file_name",length=255)
    private String fileName;

    @Column(name="xml_content")
    private Clob xmlContent;

    [...]
}

In this sample, i have a the following error:

在此示例中，我有以下错误：

    15.03.2010 16:37:59 [ERROR] org.springframework.web.context.ContextLoader       Context initialization failed
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor#0' defined in class path resource [config/persistenceContext.xml]: Initialization of bean failed; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'entityManagerFactory' defined in class path resource [config/persistenceContext.xml]: Invocation of init method failed; nested exception is javax.persistence.PersistenceException: [PersistenceUnit: test] Unable to configure EntityManagerFactory
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:480)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.run(AbstractAutowireCapableBeanFactory.java:409)
    at java.security.AccessController.doPrivileged(Native Method)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:380)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getObject(AbstractBeanFactory.java:264)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:221)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:261)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:185)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:164)
    at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:881)
    at org.springframework.context.support.AbstractApplicationContext.registerBeanPostProcessors(AbstractApplicationContext.java:597)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:366)
    at org.springframework.web.context.ContextLoader.createWebApplicationContext(ContextLoader.java:255)
    at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:199)
    at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:45)
    at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:3843)
    at org.apache.catalina.core.StandardContext.start(StandardContext.java:4350)
    at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1045)
    at org.apache.catalina.core.StandardHost.start(StandardHost.java:719)
    at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1045)
    at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:443)
    at org.apache.catalina.core.StandardService.start(StandardService.java:516)
    at org.apache.catalina.core.StandardServer.start(StandardServer.java:710)
    at org.apache.catalina.startup.Catalina.start(Catalina.java:578)
    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.apache.catalina.startup.Bootstrap.start(Bootstrap.java:288)
    at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:413)
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'entityManagerFactory' defined in class path resource [config/persistenceContext.xml]: Invocation of init method failed; nested exception is javax.persistence.PersistenceException: [PersistenceUnit: test] Unable to configure EntityManagerFactory
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1337)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:473)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.run(AbstractAutowireCapableBeanFactory.java:409)
    at java.security.AccessController.doPrivileged(Native Method)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:380)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getObject(AbstractBeanFactory.java:264)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:221)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:261)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:185)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:164)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBeansOfType(DefaultListableBeanFactory.java:308)
    at org.springframework.beans.factory.BeanFactoryUtils.beansOfTypeIncludingAncestors(BeanFactoryUtils.java:270)
    at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.detectPersistenceExceptionTranslators(PersistenceExceptionTranslationInterceptor.java:122)
    at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.<init>(PersistenceExceptionTranslationInterceptor.java:78)
    at org.springframework.dao.annotation.PersistenceExceptionTranslationAdvisor.<init>(PersistenceExceptionTranslationAdvisor.java:70)
    at org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor.setBeanFactory(PersistenceExceptionTranslationPostProcessor.java:97)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1325)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:473)
    ... 29 more
Caused by: javax.persistence.PersistenceException: [PersistenceUnit: test] Unable to configure EntityManagerFactory
    at org.hibernate.ejb.Ejb3Configuration.configure(Ejb3Configuration.java:265)
    at org.hibernate.ejb.HibernatePersistence.createEntityManagerFactory(HibernatePersistence.java:125)
    at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:83)
    at org.springframework.orm.jpa.LocalEntityManagerFactoryBean.createNativeEntityManagerFactory(LocalEntityManagerFactoryBean.java:91)
    at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.afterPropertiesSet(AbstractEntityManagerFactoryBean.java:291)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1368)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1334)
    ... 46 more
Caused by: org.hibernate.AnnotationException: A Foreign key refering Reporting from Reporting has the wrong number of column. should be 2
    at org.hibernate.cfg.annotations.TableBinder.bindFk(TableBinder.java:272)
    at org.hibernate.cfg.annotations.CollectionBinder.bindCollectionSecondPass(CollectionBinder.java:1319)
    at org.hibernate.cfg.annotations.CollectionBinder.bindManyToManySecondPass(CollectionBinder.java:1158)
    at org.hibernate.cfg.annotations.CollectionBinder.bindStarToManySecondPass(CollectionBinder.java:600)
    at org.hibernate.cfg.annotations.CollectionBinder.secondPass(CollectionBinder.java:541)
    at org.hibernate.cfg.CollectionSecondPass.doSecondPass(CollectionSecondPass.java:43)
    at org.hibernate.cfg.Configuration.secondPassCompile(Configuration.java:1140)
    at org.hibernate.cfg.AnnotationConfiguration.secondPassCompile(AnnotationConfiguration.java:319)
    at org.hibernate.cfg.Configuration.buildMappings(Configuration.java:1125)
    at org.hibernate.ejb.Ejb3Configuration.buildMappings(Ejb3Configuration.java:1226)
    at org.hibernate.ejb.EventListenerConfigurator.configure(EventListenerConfigurator.java:159)
    at org.hibernate.ejb.Ejb3Configuration.configure(Ejb3Configuration.java:854)
    at org.hibernate.ejb.Ejb3Configuration.configure(Ejb3Configuration.java:191)
    at org.hibernate.ejb.Ejb3Configuration.configure(Ejb3Configuration.java:253)
    ... 52 more

采纳答案by Arthur Ronald

Well, let's see

走着瞧

You have a @AssociationOverride annotation which its APIsays:

你有一个 @AssociationOverride 注释，它的API说：

This annotation is used to override a many-to-one or one-to-onemapping of property or field for an entity relationship.

此注释用于覆盖实体关系的属性或字段的多对一或一对一映射。

And

和

It may be applied to an entity that extends a mapped superclassto override a many-to-one or one-to-one mapping defined by the mapped superclass

它可以应用于扩展映射超类的实体以覆盖由映射超类定义的多对一或一对一映射

I have not seen neither @ManyToOne nor @OnoToOne in your question. So, There is something wrong with your question.

在您的问题中，我既没有看到 @ManyToOne 也没有看到 @OnoToOne。所以，你的问题有问题。

But i have seen the following log in your StackTrace

但是我在您的 StackTrace 中看到了以下日志

A Foreign key refering Reporting from Reporting has the wrong number of column. should be 2

从 Reporting 中引用 Reporting 的外键列数错误。应该是 2

You have a Compound primary keydefined by a @EmbeddedId annotation which has two properties (fileName and xmlContent)

您有一个由 @EmbeddedId 注释定义的复合主键，该注释具有两个属性（fileName 和 xmlContent）

Now, let's see your @CollectionOfElements

现在，让我们看看你的@CollectionOfElements

@CollectionOfElements(fetch=FetchType.EAGER)
@JoinTable(name="t_reports", 
    // Your mistake goes here
    joinColumns=@JoinColumn(name="log_report"))
@Fetch(FetchMode.SELECT)
private List<ReportingFile> reports;

Its Foreign key just contains one propertywhereas your Compound primary key contains two properties. Both must match. It explains why you see this nice message

它的外键只包含一个属性，而您的复合主键包含两个属性。两者都必须匹配。它解释了为什么您会看到这条好消息

A Foreign key refering Reporting from Reporting has the wrong number of column. should be 2

从 Reporting 中引用 Reporting 的外键列数错误。应该是 2

Your right mapping should looks like this

您的正确映射应如下所示

@CollectionOfElements(fetch=FetchType.EAGER)
@JoinTable(name="t_reports", 
    joinColumns={
        // The number of columns defined by our Compound primary key (2)
        // must match the number of columns defined by its Foreign key (2)
        @JoinColumn(name="file_name", referencedColumnName="file_name"),
        @JoinColumn(name="xml_content", referencedColumnName="xml_content")})
@Fetch(FetchMode.SELECT)
private List<ReportingFile> reports;

And more: i do not know whether your target database supports a Clob as primary key. So keep it in mind.

还有更多：我不知道您的目标数据库是否支持 Clob 作为主键。所以请记住它。

Added to original answer according to your reply

根据您的回复添加到原始答案中

1oFirst scenario (without@CollectionOfElements)

1o第一个场景（没有@CollectionOfElements）

@Entity
public class Reporting {

    // You said you just want a single fileName as primary key
    @Id
    @Column(name="file_name", nullable=false)
    private String fileName;

    // You said you still want to have the whole ReportingFile object
    @Embedded
    private ReportingFile reportingFile;

    @Embeddable
    public static class ReportingFile implements Serializable {

        // You must set up insertable=false, updatable=false
        @Column(name="file_name", insertable=false, updatable=false)
        private String fileName;

        @Column(name="xml_content")
        private Clob xmlContent;

   }

}

Keep in mind the following: Hibernate does not allow you define two properties where both share the same column. Because of that, i have to define insertable=false, updatable=false in fileName property.

请记住以下几点： Hibernate不允许您定义两个共享同一列的属性。因此，我必须在 fileName 属性中定义 insertable=false、updatable=false。

And when i do the following

当我执行以下操作时

Reporting reporting = new Reporting();
reporting.setFileName("home.pdf");

ReportingFile reportingFile = new ReportingFile();
// It will not persisted because of insertable=false, updatable=false
reportingFile.setFileName("home.pdf");
reportingFile.setXmlContent(someClobObject);

session.save(reporting); // It works

2oFirst scenario (with@CollectionOfElements)

2o第一个场景（使用@CollectionOfElements）

@Entity
public class Reporting {

    // You said you just want a single fileName as primary key
    @Id
    @Column(name="file_name", nullable=false)
    private String fileName;

    // You said you still want to have the whole ReportingFile object
    @Embedded
    private ReportingFile reportingFile;

    @CollectionOfElements(fetch=FetchType.EAGER)
    @JoinTable(
        name="t_reports",
        joinColumns=@JoinColumn(name="file_name", referencedColumnName="file_name", insertable=false, updatable=false))
    private List<ReportingFile> reports;

    @Embeddable
    public static class ReportingFile implements Serializable {

        // You must set up insertable=false, updatable=false
        @Column(name="file_name", insertable=false, updatable=false)
        private String fileName;

        @Column(name="xml_content")
        private Clob xmlContent;

   }

}    

And when i do the following

当我执行以下操作时

Reporting reporting = new Reporting();
reporting.setFileName("home.pdf");

ReportingFile reportingFile = new ReportingFile();
// It will not persisted because of insertable=false, updatable=false
reportingFile.setFileName("home.pdf");
reportingFile.setXmlContent(someClobObject);

reporting.getReports().add(reportingFile);

session.save(reporting); // It does not work

Hibernate will complain

Hibernate 会抱怨

repeated column in mapping for collection: reports column: file_name

集合映射中的重复列：报告列：文件名

So, when you have a @CollectionOfElements which shares a foreign key, it will not work as expected. But you can do a workaround

因此，当您有一个共享外键的 @CollectionOfElements 时，它将无法按预期工作。但你可以做一个解决方法

@Entity
public class Reporting {

    // You said you just want a single fileName as primary key
    @Id
    @Column(name="file_name", nullable=false)
    private String fileName;

    // You said you still want to have the whole ReportingFile object
    @Embedded
    private ReportingFile reportingFile;

    // Your workaround goes here
    @CollectionOfElements(fetch=FetchType.EAGER)
    @JoinTable(
        name="t_reports",
        joinColumns=@JoinColumn(name="file_name", referencedColumnName="file_name"))
    private List<Clob> xmlContents;

    @Transient
    public List<ReportingFile> getReports() {
        List<ReportingFile> reports = new ArrayList<ReportingFile>();

        for(Clob xmlContent: getXmlContents())
            reports.add(new ReportingFile(getFileName(), xmlContent));

        return reports;
    }

    @Embeddable
    public static class ReportingFile implements Serializable {

        // required no-arg  constructor
        public ReportingFile() {}

        public ReportingFile(String fileName, Clob xmlContent) {
            this.fileName = fileName;
            this.xmlContent = xmlContent;
        }

        // You must set up insertable=false, updatable=false
        @Column(name="file_name", insertable=false, updatable=false)
        private String fileName;

        @Column(name="xml_content")
        private Clob xmlContent;

   }

}    

Notice you can define a @Embeddable class as static when using inside your owning class.

请注意，在您拥有的类中使用时，您可以将 @Embeddable 类定义为静态类。