Spring+Hibernate中PO主键带有GeneratedValue注解时出现No value specified for parameter 7

使用Spring+Hibernate开始时，PO中的主键使用了GeneratedValue注解。在MySQL中也将对应的字段设为AUTO_INCREMENT。可是每次在保存PO时，都会报出异常：

Caused by: org.hibernate.exception.SQLGrammarException: could not insert: [com.rox.app.mirrors.forum.domain.MainPost]
at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:67)
at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:43)
at org.hibernate.id.insert.AbstractReturningDelegate.performInsert(AbstractReturningDelegate.java:40)
at org.hibernate.persister.entity.AbstractEntityPersister.insert(AbstractEntityPersister.java:2158)
at org.hibernate.persister.entity.AbstractEntityPersister.insert(AbstractEntityPersister.java:2638)
at org.hibernate.action.EntityIdentityInsertAction.execute(EntityIdentityInsertAction.java:48)
at org.hibernate.engine.ActionQueue.execute(ActionQueue.java:250)
at org.hibernate.event.def.AbstractSaveEventListener.performSaveOrReplicate(AbstractSaveEventListener.java:298)
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.Def
4000
aultSaveOrUpdateEventListener.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 org.springframework.orm.hibernate3.HibernateTemplate$12.doInHibernate(HibernateTemplate.java:687)
at org.springframework.orm.hibernate3.HibernateTemplate$12.doInHibernate(HibernateTemplate.java:684)
at org.springframework.orm.hibernate3.HibernateTemplate.doExecute(HibernateTemplate.java:407)
... 9 more

Caused by: java.sql.SQLException: No value specified for parameter 7
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:910)
at com.mysql.jdbc.PreparedStatement.fillSendPacket(PreparedStatement.java:1718)
at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:1556)
at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:1500)
at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:1485)
at org.apache.commons.dbcp.DelegatingPreparedStatement.executeUpdate(DelegatingPreparedStatement.java:102)
at org.hibernate.id.IdentityGenerator$GetGeneratedKeysDelegate.executeAndExtract(IdentityGenerator.java:73)
at org.hibernate.id.insert.AbstractReturningDelegate.performInsert(AbstractReturningDelegate.java:33)

从打印的SQL语句和异常来看，在执行INSERT操作时，SQL包含将主键但是没有给它赋值。比对以前的代码和配置文件都没有变化，唯一的改动就时间hibernate.xml文件改为了注解方式。怀疑是GeneratedValue设置有问题？反复修改问题依然存在。

折腾了半天，后来才在网上查到，这是Hibernate 3.2.4中的一个BUG。之前也怀疑过是Spring或Hibernate有问题，总觉得这么一个基本功能出问题的可能性应该很小。

再检查使用的Hibernate版本，3.3.1，不是3.2.4，这个问题怎么还存在？重新梳理jar包的依赖关系，才发现hibernate-entitymanager 3.3.1中依赖了Hibernate3.2.4！将依赖关系去掉，问题解决！