ClassCastException在Hibernate/Spring 4升级后，Proxy36不能转换为SessionImplementor

Question

编辑：我不是要求什么是 ClassCastException是。我在问这是什么导致它在DetachedCriteria在Spring 4/Hibernate 4的这个特定配置下。

我想升级一些遗留代码到Spring 4/Hibernate 4，并且我碰到了一堵墙，就像Google不是很多。

我想运行一个非常简单的Hibernate库中的JUnit测试，并且它与

java.lang.ClassCastException: com.sun.proxy.$Proxy36 cannot be cast to org.hibernate.engine.spi.SessionImplementor 
    at org.hibernate.criterion.DetachedCriteria.getExecutableCriteria(DetachedCriteria.java:84) 
    at com.my.app.rest.domain.repository.AbstractHibernateRepository$6.doInHibernate(AbstractHibernateRepository.java:163) 
... 

这在Hibernate的org.hibernate.criterion.DetachedCriteria类发生故障：

/** 
* Get an executable instance of Criteria to actually run the query. 
* 
* @param session The session to associate the built Criteria with 
* 
* @return The "executable" Criteria 
*/ 
public Criteria getExecutableCriteria(Session session) { 
    impl.setSession((SessionImplementor) session); 
    return impl; 
} 

当它试图设置会话（试图将其转换为SessionImplementor），它会引发ClassCastException。

我怀疑这可能是一个AOP问题，但我不确定从哪里开始寻找。

我使用Spring 4.3.2.RELEASE和Hibernate 4.3.5.Final。

休眠-context.xml中：

<bean id="xxxSessionFactory" class="org.springframework.orm.hibernate4.LocalSessionFactoryBean"> 

     <property name="dataSource" ref="xxxDataSource" /> 

     <property name="mappingResources"> 
      <list> 
       <value>hibernate/xxxUploadDocResponseInfo.hbm.xml</value> 
      </list> 
     </property> 

     <property name="hibernateProperties"> 
      <props> 
       <prop key="hibernate.dialect">${xxx.hibernate.dialect}</prop> 
       <prop key="hibernate.show_sql">${xxx.hibernate.showsql}</prop> 
       <prop key="hibernate.hbm2ddl.auto">${xxx.hibernate.hbm2ddl}</prop> 
       <prop key="format_sql">${xxx.hibernate.formatsql}</prop> 
       <prop key="hibernate.query.substitutions">true 1, false 0</prop> 

      </props> 
     </property> 
    <alias name="xxxSessionFactory" alias="sessionFactory" /> 
</bean> 

事务的context.xml：

<bean id="xxxTransactionManager" class="org.springframework.orm.hibernate4.HibernateTransactionManager"> 
    <property name="sessionFactory" ref="sessionFactory" /> 
</bean> 

<tx:advice id="xxxTxAdvice" transaction-manager="xxxDatasourceTransactionManager"> 
    <tx:attributes> 
     <tx:method name="*" propagation="REQUIRED" /> 
     <!-- all methods begin with save have the transaction --> 
     <tx:method name="save*" propagation="REQUIRED"/> 
     <tx:method name="add*" propagation="REQUIRED"/> 
     <tx:method name="update*" propagation="REQUIRED"/> 
     <tx:method name="remove*" propagation="REQUIRED"/> 
     <tx:method name="inactivate*" propagation="REQUIRED"/> 
     <tx:method name="complete*" propagation="REQUIRED"/> 
     <tx:method name="reset*" propagation="REQUIRED"/> 
     <tx:method name="get*" read-only="true"/> 
     <tx:method name="flag*" read-only="true"/> 
     <tx:method name="doWork*" propagation="REQUIRES_NEW" /> 
    </tx:attributes> 
</tx:advice> 

<bean id="xxxDatasourceTransactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager"> 
    <constructor-arg ref="xxxDataSource" /> 
</bean> 

<aop:config> 
    <aop:pointcut id="allBusiness" expression="execution(public * com.blah.xxx.rest.business.*Business.*(..))"/> 
    <aop:advisor advice-ref="xxxTxAdvice" pointcut-ref="allBusiness"/> 
</aop:config> 

AbstractHibernateRepository.java：

public abstract class AbstractHibernateRepository<E extends Entity, S extends Serializable> extends HibernateDaoSupport { 
... 
     @SuppressWarnings("unchecked") 
protected E get(final DetachedCriteria detachedCriteria) { 
    return (E) getHibernateTemplate().execute(new HibernateCallback<E>() { 

     public E doInHibernate(Session session) { 

      Criteria criteria = detachedCriteria.getExecutableCriteria(session); 
      criteria.setResultTransformer(Criteria.DISTINCT_ROOT_ENTITY); 
      return (E) criteria.uniqueResult(); 
     } 
    }); 
} 
... 
} 

Answer 1

见HibernateTemplate#doExecute

enforceNativeSession - 是否强制本地Hibernate的Session暴露于回调代码

正如你可以在GrepCode看到：

protected Session createSessionProxy(Session session) { 
    return (Session) Proxy.newProxyInstance(
    session.getClass().getClassLoader(), new Class<?>[] {Session.class}, 
    new CloseSuppressingInvocationHandler(session)); 
} 

创建的代理只实现接口Session不界面SessionImplementor。

您必须将HibernateTemplate#execute替换为HibernateTemplate#executeWithNativeSession。