spring整合hibernate事务编程中错误分析

摘要: HibernateException: No Hibernate Session bound to thread, and configuration does not allow creation

在spring整合hibernate过程中，我们的配置文件：

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:aop="http://www.springframework.org/schema/aop"
xmlns:tx="http://www.springframework.org/schema/tx"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.2.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.2.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.2.xsd ">

<context:annotation-config></context:annotation-config>
<context:component-scan base-package="com.spring"></context:component-scan>
<!-- <context:property-placeholder location="classpath*:properties/jdbc.property" /> -->
<bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
<property name="locations" value="classpath*:properties/jdbc.properties"/>
</bean>
<bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close" >
<property name="url" value="${jdbc.url}"/>
<property name="driverClassName" value="${jdbc.driverClassName}"/>
<property name="username" value="${jdbc.username}"/>
<property name="password" value="${jdbc.password}"/>
</bean>
<bean id="SessionFactory" class="org.springframework.orm.hibernate3.annotation.AnnotationSessionFactoryBean">
<property name="dataSource" ref="dataSource"/>
<property name="annotatedClasses">
<list>
<value>com.spring.model.User</value>
<value>com.spring.model.Log</value>
</list>
</property>
<property name="hibernateProperties">
<props>
<prop key="hibernate.dialect">org.hibernate.dialect.MySQLDialect</prop>
<prop key=" hibernate.format_sql">true</prop>
</props>
</property>

</bean>

<!--利用Hibernate的事物，将sessionfactory注入 -->
<bean id="txManager" class="org.springframework.orm.hibernate3.HibernateTransactionManager">
<property name="sessionFactory" ref="SessionFactory" />
</bean>
<tx:annotation-driven transaction-manager="txManager"/>
</beans>

利用Transactional 开启事务

@Transactional
public void add(User user) {
if (userDAO == null||logDAO==null)
System.out.println("erro");
else {
userDAO.add(user);
logDAO.addLog(new Log());
}
}

调用代码

public class LogDAOImpl implements LogDAO {
private SessionFactory sessionFactory;
public SessionFactory getSessionFactory() {
return sessionFactory;
}
@Resource
public void setSessionFactory(SessionFactory sessionFactory) {
this.sessionFactory = sessionFactory;
}

/*
* 利用Spring——hibernate的事务bean管理事务，
* 写了@Transaction相当于在方法之前加了beginTranscation
* 后加了commit（），当然之前已经获取到session，
* 不再需要获取session
* @see com.spring.dao.LogDAO#addLog(com.spring.model.Log)
*/
@Override
public void addLog(Log log) {
// TODO Auto-generated method stub
// System.out.println("user added successful");
Session session=sessionFactory.getCurrentSession();
log.setMes("save success by transaction too long may be cancel");
session.save(log);

}
}

测试过程中总是报错：HibernateException: No Hibernate Session bound to thread, and configuration does not allow creation

问题分析：

在spring中我们 通过配置文件，来获取Hibernate的 SessionFactory，并将这个sessionfactory放在txmanager这个bean中管理，

我们在addLog中没有开启事务，没有结束事务，这个就是spring通过AOP在我们的save逻辑之前和之后加了事务的逻辑方法。

我们知道AOP是通过动态代理（dynamc proxy）实现的，而dynamic prox又有两种实现方式：proxy,和cglib实现

proxy实现需要类实现接口，cglib实现是直接在修改二进制码

可以看出我这里是没有加cglib的jar包导致