Spring事务配置的五种方式
前段时间对spring的事务配置做了比较深入的研究，在此之间对Spring的事务配置虽说也配置过，但是一直没有一个清楚的认识。通过这次的学习发觉Spring的事务配置只要把思路理清，还是比较好掌握的。
总结如下：
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。
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
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/aop http://www.springframework.org/schema/aop/spring-aop-2.5.xsd">
class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">
class="org.springframework.orm.hibernate3.HibernateTransactionManager">
class="org.springframework.transaction.interceptor.TransactionProxyFactoryBean">
PROPAGATION_REQUIRED
第二种方式：所有Bean共享一个代理基类
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/aop http://www.springframework.org/schema/aop/spring-aop-2.5.xsd">
class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">
class="org.springframework.orm.hibernate3.HibernateTransactionManager">
class="org.springframework.transaction.interceptor.TransactionProxyFactoryBean"
lazy-init="true"abstract="true">
PROPAGATION_REQUIRED
第三种方式：使用拦截器
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/aop http://www.springframework.org/schema/aop/spring-aop-2.5.xsd">
class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">
class="org.springframework.orm.hibernate3.HibernateTransactionManager">
class="org.springframework.transaction.interceptor.TransactionInterceptor">
PROPAGATION_REQUIRED
*Dao
transactionInterceptor
第四种方式：使用tx标签配置的拦截器
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/aop http://www.springframework.org/schema/aop/spring-aop-2.5.xsd
http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.5.xsd">
class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">
class="org.springframework.orm.hibernate3.HibernateTransactionManager">
expression="execution(* com.bluesky.spring.dao.*.*(..))"/>
pointcut-ref="interceptorPointCuts"/>
第五种方式：全注解
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/aop http://www.springframework.org/schema/aop/spring-aop-2.5.xsd
http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.5.xsd">
class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">
class="org.springframework.orm.hibernate3.HibernateTransactionManager">
此时在DAO上需加上@Transactional注解，如下：
packagecom.bluesky.spring.dao;
importjava.util.List;
importorg.hibernate.SessionFactory;
importorg.springframework.beans.factory.annotation.Autowired;
importorg.springframework.orm.hibernate3.support.HibernateDaoSupport;
importorg.springframework.stereotype.Component;
importcom.bluesky.spring.domain.User;
@Transactional
@Component("userDao")
publicclassUserDaoImplextendsHibernateDaoSupportimplementsUserDao {
publicListlistUsers() {
returnthis.getSession().createQuery("from User").list();
}
}