Spring声明式事务管理与配置介绍

绝地灬酷狼 2022-09-21 15:18 180阅读 0赞

#  #

### 一、Spring声明式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。

具体如下图：

![Spring声明式事务配置][Spring]

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

[View Row Code][]

<table style="margin:0px!important; padding:0px!important; border:1px solid rgb(170,170,170); font-family:Menlo,Monaco,Consolas,monospace; line-height:1.5em; border-collapse:collapse; width:656px; background-color:rgb(240,240,240)"> 
 <tbody> 
 <tr> 
 <td style="">1</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;?xml version="1.0" encoding="UTF-8"?&gt;</td> 
 </tr> 
 <tr> 
 <td style="">2</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;beans xmlns="http://www.springframework.org/schema/beans"</td> 
 </tr> 
 <tr> 
 <td style="">3</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context"</td> 
 </tr> 
 <tr> 
 <td style="">4</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> xmlns:aop="http://www.springframework.org/schema/aop"</td> 
 </tr> 
 <tr> 
 <td style="">5</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> xsi:schemaLocation="http://www.springframework.org/schema/beans </td> 
 </tr> 
 <tr> 
 <td style="">6</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> http://www.springframework.org/schema/beans/spring-beans-2.5.xsd</td> 
 </tr> 
 <tr> 
 <td style="">7</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> http://www.springframework.org/schema/context</td> 
 </tr> 
 <tr> 
 <td style="">8</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> http://www.springframework.org/schema/context/spring-context-2.5.xsd</td> 
 </tr> 
 <tr> 
 <td style="">9</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-2.5.xsd"&gt;</td> 
 </tr> 
 <tr> 
 <td style="">10</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> </td> 
 </tr> 
 <tr> 
 <td style="">11</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;bean id="sessionFactory" class="org.springframework.orm.hibernate3.LocalSessionFactoryBean"&gt;</td> 
 </tr> 
 <tr> 
 <td style="">12</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;property name="configLocation" value="classpath:hibernate.cfg.xml" /&gt;</td> 
 </tr> 
 <tr> 
 <td style="">13</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;property name="configurationClass" value="org.hibernate.cfg.AnnotationConfiguration" /&gt;</td> 
 </tr> 
 <tr> 
 <td style="">14</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;/bean&gt;</td> 
 </tr> 
 <tr> 
 <td style="">15</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> </td> 
 </tr> 
 <tr> 
 <td style="">16</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;!-- 定义事务管理器（声明式的事务） --&gt;</td> 
 </tr> 
 <tr> 
 <td style="">17</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;bean id="transactionManager" class="org.springframework.orm.hibernate3.HibernateTransactionManager"&gt;</td> 
 </tr> 
 <tr> 
 <td style="">18</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;property name="sessionFactory" ref="sessionFactory" /&gt;</td> 
 </tr> 
 <tr> 
 <td style="">19</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;/bean&gt;</td> 
 </tr> 
 <tr> 
 <td style="">20</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> </td> 
 </tr> 
 <tr> 
 <td style="">21</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;!-- 配置DAO --&gt;</td> 
 </tr> 
 <tr> 
 <td style="">22</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;bean id="userDaoTarget" class="com.bluesky.spring.dao.UserDaoImpl"&gt;</td> 
 </tr> 
 <tr> 
 <td style="">23</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;property name="sessionFactory" ref="sessionFactory" /&gt;</td> 
 </tr> 
 <tr> 
 <td style="">24</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;/bean&gt;</td> 
 </tr> 
 <tr> 
 <td style="">25</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> </td> 
 </tr> 
 <tr> 
 <td style="">26</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;bean id="userDao" class="org.springframework.transaction.interceptor.TransactionProxyFactoryBean"&gt;</td> 
 </tr> 
 <tr> 
 <td style="">27</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;!-- 配置事务管理器 --&gt;</td> 
 </tr> 
 <tr> 
 <td style="">28</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;property name="transactionManager" ref="transactionManager" /&gt;</td> 
 </tr> 
 <tr> 
 <td style="">29</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;property name="target" ref="userDaoTarget" /&gt;</td> 
 </tr> 
 <tr> 
 <td style="">30</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;property name="proxyInterfaces" value="com.bluesky.spring.dao.GeneratorDao" /&gt;</td> 
 </tr> 
 <tr> 
 <td style="">31</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;!-- 配置事务属性 --&gt;</td> 
 </tr> 
 <tr> 
 <td style="">32</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;property name="transactionAttributes"&gt;</td> 
 </tr> 
 <tr> 
 <td style="">33</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;props&gt;</td> 
 </tr> 
 <tr> 
 <td style="">34</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;prop key="*"&gt;PROPAGATION_REQUIRED&lt;/prop&gt;</td> 
 </tr> 
 <tr> 
 <td style="">35</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;/props&gt;</td> 
 </tr> 
 <tr> 
 <td style="">36</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;/property&gt;</td> 
 </tr> 
 <tr> 
 <td style="">37</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;/bean&gt;</td> 
 </tr> 
 <tr> 
 <td style="">38</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;/beans&gt;</td> 
 </tr> 
 </tbody> 
</table>

第二种方式：所有Bean共享一个代理基类

[View Row Code][]

<table style="margin:0px!important; padding:0px!important; border:1px solid rgb(170,170,170); font-family:Menlo,Monaco,Consolas,monospace; line-height:1.5em; border-collapse:collapse; width:649px; background-color:rgb(240,240,240)"> 
 <tbody> 
 <tr> 
 <td style="">1</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> ......</td> 
 </tr> 
 <tr> 
 <td style="">2</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;bean id="sessionFactory" class="org.springframework.orm.hibernate3.LocalSessionFactoryBean"&gt;</td> 
 </tr> 
 <tr> 
 <td style="">3</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;property name="configLocation" value="classpath:hibernate.cfg.xml" /&gt;</td> 
 </tr> 
 <tr> 
 <td style="">4</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;property name="configurationClass" value="org.hibernate.cfg.AnnotationConfiguration" /&gt;</td> 
 </tr> 
 <tr> 
 <td style="">5</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;/bean&gt;</td> 
 </tr> 
 <tr> 
 <td style="">6</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> </td> 
 </tr> 
 <tr> 
 <td style="">7</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;!-- 定义事务管理器（声明式的事务） --&gt;</td> 
 </tr> 
 <tr> 
 <td style="">8</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;bean id="transactionManager" class="org.springframework.orm.hibernate3.HibernateTransactionManager"&gt;</td> 
 </tr> 
 <tr> 
 <td style="">9</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;property name="sessionFactory" ref="sessionFactory" /&gt;</td> 
 </tr> 
 <tr> 
 <td style="">10</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;/bean&gt;</td> 
 </tr> 
 <tr> 
 <td style="">11</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> </td> 
 </tr> 
 <tr> 
 <td style="">12</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;bean id="transactionBase" class="org.springframework.transaction.interceptor.TransactionProxyFactoryBean" lazy-init="true" abstract="true"&gt;</td> 
 </tr> 
 <tr> 
 <td style="">13</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;!-- 配置事务管理器 --&gt;</td> 
 </tr> 
 <tr> 
 <td style="">14</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;property name="transactionManager" ref="transactionManager" /&gt;</td> 
 </tr> 
 <tr> 
 <td style="">15</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;!-- 配置事务属性 --&gt;</td> 
 </tr> 
 <tr> 
 <td style="">16</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;property name="transactionAttributes"&gt;</td> 
 </tr> 
 <tr> 
 <td style="">17</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;props&gt;</td> 
 </tr> 
 <tr> 
 <td style="">18</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;prop key="*"&gt;PROPAGATION_REQUIRED&lt;/prop&gt;</td> 
 </tr> 
 <tr> 
 <td style="">19</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;/props&gt;</td> 
 </tr> 
 <tr> 
 <td style="">20</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;/property&gt;</td> 
 </tr> 
 <tr> 
 <td style="">21</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;/bean&gt;</td> 
 </tr> 
 <tr> 
 <td style="">22</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> </td> 
 </tr> 
 <tr> 
 <td style="">23</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;!-- 配置DAO --&gt;</td> 
 </tr> 
 <tr> 
 <td style="">24</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;bean id="userDaoTarget" class="com.bluesky.spring.dao.UserDaoImpl"&gt;</td> 
 </tr> 
 <tr> 
 <td style="">25</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;property name="sessionFactory" ref="sessionFactory" /&gt;</td> 
 </tr> 
 <tr> 
 <td style="">26</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;/bean&gt;</td> 
 </tr> 
 <tr> 
 <td style="">27</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> </td> 
 </tr> 
 <tr> 
 <td style="">28</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;bean id="userDao" parent="transactionBase"&gt;</td> 
 </tr> 
 <tr> 
 <td style="">29</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;property name="target" ref="userDaoTarget" /&gt;</td> 
 </tr> 
 <tr> 
 <td style="">30</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;/bean&gt;</td> 
 </tr> 
 </tbody> 
</table>

第三种方式：使用拦截器

[View Row Code][]

<table style="margin:0px!important; padding:0px!important; border:1px solid rgb(170,170,170); font-family:Menlo,Monaco,Consolas,monospace; line-height:1.5em; border-collapse:collapse; width:633px; background-color:rgb(240,240,240)"> 
 <tbody> 
 <tr> 
 <td style="">1</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> ......</td> 
 </tr> 
 <tr> 
 <td style="">2</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;bean id="sessionFactory" class="org.springframework.orm.hibernate3.LocalSessionFactoryBean"&gt;</td> 
 </tr> 
 <tr> 
 <td style="">3</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;property name="configLocation" value="classpath:hibernate.cfg.xml" /&gt;</td> 
 </tr> 
 <tr> 
 <td style="">4</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;property name="configurationClass" value="org.hibernate.cfg.AnnotationConfiguration" /&gt;</td> 
 </tr> 
 <tr> 
 <td style="">5</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;/bean&gt;</td> 
 </tr> 
 <tr> 
 <td style="">6</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> </td> 
 </tr> 
 <tr> 
 <td style="">7</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;!-- 定义事务管理器（声明式的事务） --&gt;</td> 
 </tr> 
 <tr> 
 <td style="">8</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;bean id="transactionManager" class="org.springframework.orm.hibernate3.HibernateTransactionManager"&gt;</td> 
 </tr> 
 <tr> 
 <td style="">9</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;property name="sessionFactory" ref="sessionFactory" /&gt;</td> 
 </tr> 
 <tr> 
 <td style="">10</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;/bean&gt;</td> 
 </tr> 
 <tr> 
 <td style="">11</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> </td> 
 </tr> 
 <tr> 
 <td style="">12</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;bean id="transactionInterceptor" class="org.springframework.transaction.interceptor.TransactionInterceptor"&gt;</td> 
 </tr> 
 <tr> 
 <td style="">13</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;property name="transactionManager" ref="transactionManager" /&gt;</td> 
 </tr> 
 <tr> 
 <td style="">14</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;!-- 配置事务属性 --&gt;</td> 
 </tr> 
 <tr> 
 <td style="">15</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;property name="transactionAttributes"&gt;</td> 
 </tr> 
 <tr> 
 <td style="">16</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;props&gt;</td> 
 </tr> 
 <tr> 
 <td style="">17</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;prop key="*"&gt;PROPAGATION_REQUIRED&lt;/prop&gt;</td> 
 </tr> 
 <tr> 
 <td style="">18</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;/props&gt;</td> 
 </tr> 
 <tr> 
 <td style="">19</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;/property&gt;</td> 
 </tr> 
 <tr> 
 <td style="">20</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;/bean&gt;</td> 
 </tr> 
 <tr> 
 <td style="">21</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> </td> 
 </tr> 
 <tr> 
 <td style="">22</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;bean class="org.springframework.aop.framework.autoproxy.BeanNameAutoProxyCreator"&gt;</td> 
 </tr> 
 <tr> 
 <td style="">23</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;property name="beanNames"&gt;</td> 
 </tr> 
 <tr> 
 <td style="">24</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;list&gt;</td> 
 </tr> 
 <tr> 
 <td style="">25</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;value&gt;*Dao&lt;/value&gt;</td> 
 </tr> 
 <tr> 
 <td style="">26</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;/list&gt;</td> 
 </tr> 
 <tr> 
 <td style="">27</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;/property&gt;</td> 
 </tr> 
 <tr> 
 <td style="">28</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;property name="interceptorNames"&gt;</td> 
 </tr> 
 <tr> 
 <td style="">29</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;list&gt;</td> 
 </tr> 
 <tr> 
 <td style="">30</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;value&gt;transactionInterceptor&lt;/value&gt;</td> 
 </tr> 
 <tr> 
 <td style="">31</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;/list&gt;</td> 
 </tr> 
 <tr> 
 <td style="">32</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;/property&gt;</td> 
 </tr> 
 <tr> 
 <td style="">33</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;/bean&gt;</td> 
 </tr> 
 <tr> 
 <td style="">34</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> </td> 
 </tr> 
 <tr> 
 <td style="">35</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;!-- 配置DAO --&gt;</td> 
 </tr> 
 <tr> 
 <td style="">36</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;bean id="userDao" class="com.bluesky.spring.dao.UserDaoImpl"&gt;</td> 
 </tr> 
 <tr> 
 <td style="">37</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;property name="sessionFactory" ref="sessionFactory" /&gt;</td> 
 </tr> 
 <tr> 
 <td style="">38</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;/bean&gt;</td> 
 </tr> 
 </tbody> 
</table>

第四种方式：使用tx标签配置的拦截器

[View Row Code][]

<table style="margin:0px!important; padding:0px!important; border:1px solid rgb(170,170,170); font-family:Menlo,Monaco,Consolas,monospace; line-height:1.5em; border-collapse:collapse; width:603px; background-color:rgb(240,240,240)"> 
 <tbody> 
 <tr> 
 <td style="">1</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;?xml version="1.0" encoding="UTF-8"?&gt;</td> 
 </tr> 
 <tr> 
 <td style="">2</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;beans xmlns="http://www.springframework.org/schema/beans"</td> 
 </tr> 
 <tr> 
 <td style="">3</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"</td> 
 </tr> 
 <tr> 
 <td style="">4</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> xmlns:context="http://www.springframework.org/schema/context"</td> 
 </tr> 
 <tr> 
 <td style="">5</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> xmlns:aop="http://www.springframework.org/schema/aop"</td> 
 </tr> 
 <tr> 
 <td style="">6</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> xmlns:tx="http://www.springframework.org/schema/tx"</td> 
 </tr> 
 <tr> 
 <td style="">7</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> xsi:schemaLocation="http://www.springframework.org/schema/beans </td> 
 </tr> 
 <tr> 
 <td style="">8</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> http://www.springframework.org/schema/beans/spring-beans-2.5.xsd</td> 
 </tr> 
 <tr> 
 <td style="">9</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> http://www.springframework.org/schema/context</td> 
 </tr> 
 <tr> 
 <td style="">10</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> http://www.springframework.org/schema/context/spring-context-2.5.xsd</td> 
 </tr> 
 <tr> 
 <td style="">11</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-2.5.xsd</td> 
 </tr> 
 <tr> 
 <td style="">12</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.5.xsd"&gt;</td> 
 </tr> 
 <tr> 
 <td style="">13</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;context:annotation-config /&gt;</td> 
 </tr> 
 <tr> 
 <td style="">14</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;context:component-scan base-package="com.bluesky" /&gt;</td> 
 </tr> 
 <tr> 
 <td style="">15</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> </td> 
 </tr> 
 <tr> 
 <td style="">16</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;bean id="sessionFactory" class="org.springframework.orm.hibernate3.LocalSessionFactoryBean"&gt;</td> 
 </tr> 
 <tr> 
 <td style="">17</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;property name="configLocation" value="classpath:hibernate.cfg.xml" /&gt;</td> 
 </tr> 
 <tr> 
 <td style="">18</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;property name="configurationClass" value="org.hibernate.cfg.AnnotationConfiguration" /&gt;</td> 
 </tr> 
 <tr> 
 <td style="">19</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;/bean&gt;</td> 
 </tr> 
 <tr> 
 <td style="">20</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> </td> 
 </tr> 
 <tr> 
 <td style="">21</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;!-- 定义事务管理器（声明式的事务） --&gt;</td> 
 </tr> 
 <tr> 
 <td style="">22</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;bean id="transactionManager" class="org.springframework.orm.hibernate3.HibernateTransactionManager"&gt;</td> 
 </tr> 
 <tr> 
 <td style="">23</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;property name="sessionFactory" ref="sessionFactory" /&gt;</td> 
 </tr> 
 <tr> 
 <td style="">24</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;/bean&gt;</td> 
 </tr> 
 <tr> 
 <td style="">25</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> </td> 
 </tr> 
 <tr> 
 <td style="">26</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;tx:advice id="txAdvice" transaction-manager="transactionManager"&gt;</td> 
 </tr> 
 <tr> 
 <td style="">27</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;tx:attributes&gt;</td> 
 </tr> 
 <tr> 
 <td style="">28</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;tx:method name="*" propagation="REQUIRED" /&gt;</td> 
 </tr> 
 <tr> 
 <td style="">29</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;/tx:attributes&gt;</td> 
 </tr> 
 <tr> 
 <td style="">30</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;/tx:advice&gt;</td> 
 </tr> 
 <tr> 
 <td style="">31</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> </td> 
 </tr> 
 <tr> 
 <td style="">32</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;aop:config&gt;</td> 
 </tr> 
 <tr> 
 <td style="">33</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;aop:pointcut id="interceptorPointCuts" expression="execution(* com.bluesky.spring.dao.*.*(..))" /&gt;</td> 
 </tr> 
 <tr> 
 <td style="">34</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;aop:advisor advice-ref="txAdvice" pointcut-ref="interceptorPointCuts" /&gt;</td> 
 </tr> 
 <tr> 
 <td style="">35</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word; background-color:rgb(245,245,245)"> &lt;/aop:config&gt;</td> 
 </tr> 
 <tr> 
 <td style="">36</td> 
 <td style="margin:0px; padding:0px 0.4em; border:0px; border-collapse:collapse; color:rgb(51,51,51); white-space:pre-wrap; word-wrap:break-word"> &lt;/bean&gt;</td> 
 </tr> 
 </tbody> 
</table>

第五种方式：全注解

[View Row Code][]

此时在DAO上需加上@Transactional注解，如下：

[View Row Code][]

### 二、事务的传播属性（Propagation） ###

Propagation ：key属性确定代理应该给哪个方法增加事务行为。这样的属性最重要的部份是传播行为。有以下选项可供使用：PROPAGATION\_REQUIRED--支持当前事务，如果当前没有事务，就新建一个事务。这是最常见的选择。

*  PROPAGATION\_REQUIRED--加入当前正要执行的事务不在另外一个事务里，那么就起一个新的事务
 *  PROPAGATION\_SUPPORTS--支持当前事务，如果当前没有事务，就以非事务方式执行。
 *  PROPAGATION\_MANDATORY--支持当前事务，如果当前没有事务，就抛出异常。
 *  PROPAGATION\_REQUIRES\_NEW--新建事务，如果当前存在事务，把当前事务挂起。
 *  PROPAGATION\_NOT\_SUPPORTED--以非事务方式执行操作，如果当前存在事务，就把当前事务挂起。
 *  PROPAGATION\_NEVER--以非事务方式执行，如果当前存在事务，则抛出异常。

1： PROPAGATION\_REQUIRED

加入当前正要执行的事务不在另外一个事务里，那么就起一个新的事务。

比如说，ServiceB.methodB的事务级别定义为PROPAGATION\_REQUIRED, 那么由于执行ServiceA.methodA的时候，ServiceA.methodA已经起了事务，这时调用ServiceB.methodB，ServiceB.methodB看到自己已经运行在ServiceA.methodA的事务内部，就不再起新的事务。而假如ServiceA.methodA运行的时候发现自己没有在事务中，他就会为自己分配一个事务。这样，在ServiceA.methodA或者在ServiceB.methodB内的任何地方出现异常，事务都会被回滚。即使ServiceB.methodB的事务已经被提交，但是ServiceA.methodA在接下来fail要回滚，ServiceB.methodB也要回滚。

2： PROPAGATION\_SUPPORTS

如果当前在事务中，即以事务的形式运行，如果当前不再一个事务中，那么就以非事务的形式运行。

3： PROPAGATION\_MANDATORY

必须在一个事务中运行。也就是说，他只能被一个父事务调用。否则，他就要抛出异常。

4： PROPAGATION\_REQUIRES\_NEW

这个就比较绕口了。 比如我们设计ServiceA.methodA的事务级别为PROPAGATION\_REQUIRED，ServiceB.methodB的事务级别为PROPAGATION\_REQUIRES\_NEW，那么当执行到ServiceB.methodB的时候，ServiceA.methodA所在的事务就会挂起，ServiceB.methodB会起一个新的事务，等待ServiceB.methodB的事务完成以后，他才继续执行。他与PROPAGATION\_REQUIRED 的事务区别在于事务的回滚程度了。因为ServiceB.methodB是新起一个事务，那么就是存在两个不同的事务。如果ServiceB.methodB已经提交，那么ServiceA.methodA失败回滚，ServiceB.methodB是不会回滚的。如果ServiceB.methodB失败回滚，如果他抛出的异常被ServiceA.methodA捕获，ServiceA.methodA事务仍然可能提交。

5： PROPAGATION\_NOT\_SUPPORTED

当前不支持事务。比如ServiceA.methodA的事务级别是PROPAGATION\_REQUIRED ，而ServiceB.methodB的事务级别是PROPAGATION\_NOT\_SUPPORTED ，那么当执行到ServiceB.methodB时，ServiceA.methodA的事务挂起，而他以非事务的状态运行完，再继续ServiceA.methodA的事务。

6： PROPAGATION\_NEVER

不能在事务中运行。假设ServiceA.methodA的事务级别是PROPAGATION\_REQUIRED， 而ServiceB.methodB的事务级别是PROPAGATION\_NEVER ，那么ServiceB.methodB就要抛出异常了。

7： PROPAGATION\_NESTED

理解Nested的关键是savepoint。他与PROPAGATION\_REQUIRES\_NEW的区别是，PROPAGATION\_REQUIRES\_NEW另起一个事务，将会与他的父事务相互独立，而Nested的事务和他的父事务是相依的，他的提交是要等和他的父事务一块提交的。也就是说，如果父事务最后回滚，他也要回滚的。

而Nested事务的好处是他有一个savepoint。

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也就是说ServiceB.methodB失败回滚，那么ServiceA.methodA也会回滚到savepoint点上，ServiceA.methodA可以选择另外一个分支，比如：

ServiceC.methodC，继续执行，来尝试完成自己的事务。

但是这个事务并没有在EJB标准中定义。

### 三、Spring事务的隔离级别（Isolation level） ###

1. ISOLATION\_DEFAULT： 这是一个PlatfromTransactionManager默认的隔离级别，使用数据库默认的事务隔离级别。

另外四个与JDBC的隔离级别相对应。

2. ISOLATION\_READ\_UNCOMMITTED： 这是事务最低的隔离级别，它充许令外一个事务可以看到这个事务未提交的数据。

这种隔离级别会产生脏读，不可重复读和幻像读。

3. ISOLATION\_READ\_COMMITTED： 保证一个事务修改的数据提交后才能被另外一个事务读取。另外一个事务不能读取该事务未提交的数据。

4. ISOLATION\_REPEATABLE\_READ： 这种事务隔离级别可以防止脏读，不可重复读。但是可能出现幻像读。