Exception in thread "main" org.hibernate.id.IdentifierGenerationException: attem

今天在做Hibernate中1多1双向关联映射的实例时,

保存时,报下面的错误..

 

检查了一下..具体Hibernate配置代码是没有问题:

Person_SX_PK_One_to_One.hbm.xml:

 

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">

<hibernate-mapping>
	<class name="pack.java.model.Person_SX_PK_One_to_One" table="ZHT_PERSON_SX_PK_ONE_TO_ONE">
		<id name="id" column="ID">
			<generator class="identity"></generator>
		</id>
		
		<property name="name" column="NAME"></property>
		<property name="age" column="AGE"></property>
		
		<!-- 1对1,引用address对象, -->
		<one-to-one 
			name="addressSXPKOneToOne" 
			class="pack.java.model.Address_SX_PK_One_To_One" 
			fetch="select" 
			lazy="false"
			cascade="all">
		</one-to-one>
	</class>
</hibernate-mapping>

 

    Address_SX_PK_One_To_One.hbm.xml:

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">

<hibernate-mapping>
	<class name="pack.java.model.Address_SX_PK_One_To_One" table="ZHT_ADDRESS_SX_PK_ONE_TO_ONE">
		<id column="ID" name="id">
			<!-- generator 主键生成策略,配制成foreign,外键,是引用主表person的对象。 -->
			<generator class="foreign">
				<param name="property">personSXPKOneToOne</param>
			</generator>
		</id>
		
		<property name="addressDetail" column="ADDRESSDETAIL"></property>
		
		<!-- 表示在address表中,存在外键约束,外键参考相关表person对象。 -->
		<one-to-one name="personSXPKOneToOne" constrained="true"></one-to-one>
	</class>
</hibernate-mapping>

 

 

然后写了一个test类,测试时,

给person设置属性值并且给peson设置address对象,然后保存person. 现在就发生错误了.

 

原因是因为没有给address对象设置person对象. 所以报如下错误,。原因在于address引用了person表的主键,如果不设置.则会引用一个null值..不能进save操作,所以,需要注意。

 

 

 

错误信息:

Exception in thread "main" org.hibernate.id.IdentifierGenerationException: attempted to assign id from null one-to-one property: personSXPKOneToOne
 at org.hibernate.id.ForeignGenerator.generate(ForeignGenerator.java:44)
 at org.hibernate.event.def.AbstractSaveEventListener.saveWithGeneratedId
(AbstractSaveEventListener.java:99)
 at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.saveWithGeneratedOrRequestedId(DefaultSaveOrUpdateEventListener.java:187)
 at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.entityIsTransient(DefaultSaveOrUpdateEventListener.java:172)
 at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.performSaveOrUpdate(DefaultSaveOrUpdateEventListener.java:94)
 at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.onSaveOrUpdate(DefaultSaveOrUpdateEventListener.java:70)
 at org.hibernate.impl.SessionImpl.fireSaveOrUpdate(SessionImpl.java:507)
 at org.hibernate.impl.SessionImpl.saveOrUpdate(SessionImpl.java:499)
 at org.hibernate.engine.CascadingAction$5.cascade(CascadingAction.java:218)
 at org.hibernate.engine.Cascade.cascadeToOne(Cascade.java:268)
 at org.hibernate.engine.Cascade.cascadeAssociation(Cascade.java:216)
 at org.hibernate.engine.Cascade.cascadeProperty(Cascade.java:169)
 at org.hibernate.engine.Cascade.cascade(Cascade.java:130)
 at org.hibernate.event.def.AbstractSaveEventListener.cascadeAfterSave(AbstractSaveEventListener.java:456)
 at org.hibernate.event.def.AbstractSaveEventListener.performSaveOrReplicate(AbstractSaveEventListener.java:334)
 at org.hibernate.event.def.AbstractSaveEventListener.performSave(AbstractSaveEventListener.java:181)
 at org.hibernate.event.def.AbstractSaveEventListener.saveWithGeneratedId(AbstractSaveEventListener.java:107)
 at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.saveWithGeneratedOrRequestedId(DefaultSaveOrUpdateEventListener.java:187)
 at org.hibernate.event.def.DefaultSaveEventListener.saveWithGeneratedOrRequestedId(DefaultSaveEventListener.java:33)
 at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.entityIsTransient(DefaultSaveOrUpdateEventListener.java:172)
 at org.hibernate.event.def.DefaultSaveEventListener.performSaveOrUpdate(DefaultSaveEventListener.java:27)
 at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.onSaveOrUpdate(DefaultSaveOrUpdateEventListener.java:70)
 at org.hibernate.impl.SessionImpl.fireSave(SessionImpl.java:535)
 at org.hibernate.impl.SessionImpl.save(SessionImpl.java:523)
 at org.hibernate.impl.SessionImpl.save(SessionImpl.java:519)
 at pack.java.test.HibernateDemoXS_PK_OneToOne.savePerson(HibernateDemoXS_PK_OneToOne.java:31)
 at pack.java.test.HibernateDemoXS_PK_OneToOne.main(HibernateDemoXS_PK_OneToOne.java:15)

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