Java事务的类型有三种：
JDBC事务、 可以将多个 SQL 语句结合到一个事务中。JDBC 事务的一个缺点是事务的范围局限于一个数据库连接。一个 JDBC 事务不能跨越多个数据库
JTA（Java Transaction API）事务、事务可以跨越多个数据库或多个DAO，使用也比较复杂。
容器事务。主要指的是J2EE应用服务器提供的事务管理，局限于EJB应用使用。
spring事务的配置方式编程式事务和声明式事务，相信大家都知道是有5种，但我们经常使用的应该就是基于注解和tx标签配置拦截器两种方式了
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<
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
>
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ps：声明式事务管理建立在AOP之上的。其本质是对方法前后进行拦截，然后在目标方法开始之前创建或者加入一个事务，在执行完目标方法之后根据执行情况提交或者回滚事务。
1、基于注解，DAO上需加上@Transactional注解
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<
tx:annotation-driven
transaction-manager
=
"transactionManager"
/>
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2、使用tx标签配置的拦截器
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<
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
>
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3、使用拦截器
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<
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
>
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4、所有Bean共享一个代理基类
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<
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
>
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5、每个Bean都有一个代理
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<
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
>
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