在前文
深入浅出学习Spring框架(一):通过Demo阐述IoC和DI的优势所在、
分别介绍了Spring的核心功能——IoC和AOP,光讲知识远远不够,重要的得实践才行,今天来谈谈在IoC和AOP基础上配置事务。
Spring配置文件中关于事务配置总是由三个组成部分,分别是DataSource、TransactionManager和代理机制这三部分,无论哪种配置方式,一般变化的只是代理机制这部分。
DataSource、TransactionManager这两部分只是会根据数据访问方式有所变化,比如使用Hibernate进行数据访问时,DataSource实际为SessionFactory,TransactionManager的实现为HibernateTransactionManager。
具体如下图:
根据代理机制的不同,总结了五种Spring事务的配置方式,配置文件如下:
第一种方式:每个Bean都有一个代理
<?xmlversion="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"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-2.5.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-2.5.xsd
http://www.springframework.org/schema/aophttp://www.springframework.org/schema/aop/spring-aop-2.5.xsd"> <bean id="sessionFactory"
class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">
<property name="configLocation" value="classpath:hibernate.cfg.xml" />
<property name="configurationClass" value="org.hibernate.cfg.AnnotationConfiguration" />
</bean> <!-- 定义事务管理器(声明式的事务) -->
<bean id="transactionManager"
class="org.springframework.orm.hibernate3.HibernateTransactionManager">
<property name="sessionFactory" ref="sessionFactory" />
</bean> <!-- 配置DAO -->
<bean id="userDaoTarget" class="com.bluesky.spring.dao.UserDaoImpl">
<property name="sessionFactory" ref="sessionFactory" />
</bean> <bean id="userDao"
class="org.springframework.transaction.interceptor.TransactionProxyFactoryBean">
<!-- 配置事务管理器 -->
<property name="transactionManager" ref="transactionManager" />
<property name="target" ref="userDaoTarget" />
<property name="proxyInterfaces" value="com.bluesky.spring.dao.GeneratorDao" />
<!-- 配置事务属性 -->
<property name="transactionAttributes">
<props>
<prop key="*">PROPAGATION_REQUIRED</prop>
</props>
</property>
</bean>
</beans>
第二种方式:所有Bean共享一个代理基类
<?xmlversion="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"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-2.5.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-2.5.xsd
http://www.springframework.org/schema/aophttp://www.springframework.org/schema/aop/spring-aop-2.5.xsd"> <bean id="sessionFactory"
class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">
<property name="configLocation" value="classpath:hibernate.cfg.xml" />
<property name="configurationClass" value="org.hibernate.cfg.AnnotationConfiguration" />
</bean> <!-- 定义事务管理器(声明式的事务) -->
<bean id="transactionManager"
class="org.springframework.orm.hibernate3.HibernateTransactionManager">
<property name="sessionFactory" ref="sessionFactory" />
</bean> <bean id="transactionBase"
class="org.springframework.transaction.interceptor.TransactionProxyFactoryBean"
lazy-init="true" abstract="true">
<!-- 配置事务管理器 -->
<property name="transactionManager" ref="transactionManager" />
<!-- 配置事务属性 -->
<property name="transactionAttributes">
<props>
<prop key="*">PROPAGATION_REQUIRED</prop>
</props>
</property>
</bean> <!-- 配置DAO -->
<bean id="userDaoTarget" class="com.bluesky.spring.dao.UserDaoImpl">
<property name="sessionFactory" ref="sessionFactory" />
</bean> <bean id="userDao" parent="transactionBase" >
<property name="target" ref="userDaoTarget" />
</bean>
</beans>
第三种方式:使用拦截器
<?xmlversion="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"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-2.5.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-2.5.xsd
http://www.springframework.org/schema/aophttp://www.springframework.org/schema/aop/spring-aop-2.5.xsd"> <bean id="sessionFactory"
class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">
<property name="configLocation" value="classpath:hibernate.cfg.xml" />
<property name="configurationClass" value="org.hibernate.cfg.AnnotationConfiguration" />
</bean> <!-- 定义事务管理器(声明式的事务) -->
<bean id="transactionManager"
class="org.springframework.orm.hibernate3.HibernateTransactionManager">
<property name="sessionFactory" ref="sessionFactory" />
</bean> <bean id="transactionInterceptor"
class="org.springframework.transaction.interceptor.TransactionInterceptor">
<property name="transactionManager" ref="transactionManager" />
<!-- 配置事务属性 -->
<property name="transactionAttributes">
<props>
<prop key="*">PROPAGATION_REQUIRED</prop>
</props>
</property>
</bean> <bean class="org.springframework.aop.framework.autoproxy.BeanNameAutoProxyCreator">
<property name="beanNames">
<list>
<value>*Dao</value>
</list>
</property>
<property name="interceptorNames">
<list>
<value>transactionInterceptor</value>
</list>
</property>
</bean> <!-- 配置DAO -->
<bean id="userDao" class="com.bluesky.spring.dao.UserDaoImpl">
<property name="sessionFactory" ref="sessionFactory" />
</bean>
</beans>
第四种方式:使用tx标签配置的拦截器
<?xmlversion="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-2.5.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-2.5.xsd
http://www.springframework.org/schema/aophttp://www.springframework.org/schema/aop/spring-aop-2.5.xsd
http://www.springframework.org/schema/txhttp://www.springframework.org/schema/tx/spring-tx-2.5.xsd"> <context:annotation-config />
<context:component-scan base-package="com.bluesky" /> <bean id="sessionFactory"
class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">
<property name="configLocation" value="classpath:hibernate.cfg.xml" />
<property name="configurationClass" value="org.hibernate.cfg.AnnotationConfiguration" />
</bean> <!-- 定义事务管理器(声明式的事务) -->
<bean id="transactionManager"
class="org.springframework.orm.hibernate3.HibernateTransactionManager">
<property name="sessionFactory" ref="sessionFactory" />
</bean> <tx:advice id="txAdvice" transaction-manager="transactionManager">
<tx:attributes>
<tx:method name="*" propagation="REQUIRED" />
</tx:attributes>
</tx:advice> <aop:config>
<aop:pointcut id="interceptorPointCuts"
expression="execution(*com.bluesky.spring.dao.*.*(..))" />
<aop:advisor advice-ref="txAdvice"
pointcut-ref="interceptorPointCuts" />
</aop:config>
</beans>
第五种方式:全注解
<?xmlversion="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-2.5.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-2.5.xsd
http://www.springframework.org/schema/aophttp://www.springframework.org/schema/aop/spring-aop-2.5.xsd
http://www.springframework.org/schema/txhttp://www.springframework.org/schema/tx/spring-tx-2.5.xsd"> <context:annotation-config />
<context:component-scan base-package="com.bluesky" /> <tx:annotation-driven transaction-manager="transactionManager"/> <bean id="sessionFactory"
class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">
<property name="configLocation" value="classpath:hibernate.cfg.xml" />
<property name="configurationClass" value="org.hibernate.cfg.AnnotationConfiguration" />
</bean> <!-- 定义事务管理器(声明式的事务) -->
<bean id="transactionManager"
class="org.springframework.orm.hibernate3.HibernateTransactionManager">
<property name="sessionFactory" ref="sessionFactory" />
</bean> </beans>
此时在DAO上需加上@Transactional注解,如下:
package com.bluesky.spring.dao; import java.util.List; import org.hibernate.SessionFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.orm.hibernate3.support.HibernateDaoSupport;
import org.springframework.stereotype.Component; import com.bluesky.spring.domain.User; @Transactional
@Component("userDao")
public class UserDaoImpl extends HibernateDaoSupport implements UserDao { public List<User> listUsers() {
return this.getSession().createQuery("fromUser").list();
}
}