- 这里的项目是基于 Spring4.X + hibernate4.X架构的。最近的一个项目需要两个数据库，一个Oracle，一个是Sqlserver。业务中有一些需求需要跨库事务的一致，举个例子：合同签订保存到基于Oracle的ERP数据库，紧接着下发到Sqlserver的WMS数据库。
- 以前听说过JTA分布式事务，google到两种分布式框架：JOTM，atomikos。貌似JOTM简便点，就它了。
- 这种方式需要的jar包，首先在JOTM官网下面所有的jar包文件（文末提供下载），下图中选中的jar文件都是需要导入的
首先配置DataSource和SessionFactory
<!-- 数据库连接池 -->
<bean id="dataSource1" class="org.enhydra.jdbc.pool.StandardXAPoolDataSource">
<property name="dataSource">
<bean class="org.enhydra.jdbc.standard.StandardXADataSource" destroy-method="shutdown">
<property name="transactionManager" ref="jotm" />
<property name="driverName" value="oracle.jdbc.driver.OracleDriver" />
<property name="url" value="jdbc:oracle:thin:@192.168.1.200:1521:orcl" />
</bean>
</property>
<property name="user" value="${jdbc.username}" />
<property name="password" value="${jdbc.password}" />
</bean>
<bean id="dataSource2" class="org.enhydra.jdbc.pool.StandardXAPoolDataSource"
>
<property name="dataSource">
<bean class="org.enhydra.jdbc.standard.StandardXADataSource" destroy-method="shutdown">
<property name="transactionManager" ref="jotm" />
<property name="driverName" value="com.microsoft.sqlserver.jdbc.SQLServerDriver" />
<property name="url" value="jdbc:sqlserver://192.168.1.200:1433;DatabaseName=middle_db" />
</bean>
</property>
<property name="user" value="${jdbc2.username}" />
<property name="password" value="${jdbc2.password}" />
</bean>
<bean id="sessionFactory1"
class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
<property name="dataSource" ref="dataSource1" />
<property name="packagesToScan">
<list>
<value>com.sy.domain</value>
</list>
</property>
<property name="hibernateProperties">
<props>
<prop key="hibernate.dialect">
org.hibernate.dialect.OracleDialect
</prop>
<prop key="hibernate.show_sql">true</prop>
<prop key="hibernate.autoReconnect">true</prop>
<!-- <prop key="hibernate.hbm2ddl.auto">update</prop> -->
</props>
</property>
</bean>
<bean id="sessionFactory2"
class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
<property name="dataSource" ref="dataSource2" />
<property name="packagesToScan">
<list>
<value>com.sy.domain</value>
</list>
</property>
<property name="hibernateProperties">
<props>
<prop key="hibernate.dialect">
org.hibernate.dialect.SQLServerDialect
</prop>
<prop key="hibernate.show_sql">true</prop>
<prop key="hibernate.autoReconnect">true</prop>
<!-- <prop key="hibernate.hbm2ddl.auto">update</prop> -->
</props>
</property>
</bean>
<!-- erp.dao -->
<bean id="commonDao" class="com.sy.dao.impl.CommonDaoImpl" >
<property name="sessionFactory" ref="sessionFactory1"/>
</bean>
<!-- wms.dao -->
<bean id="commonDao2" class="com.sy.dao.impl.CommonDaoImpl" >
<property name="sessionFactory" ref="sessionFactory2"/>
</bean>
因为我们要操作两个数据库，所以配置两个datasource，两个sessionfactory。需要注意的是我们这里是JOTM和xapool实现的分布式事务。JOTM实现了TransactionManager的功能，xapool通过使用非XA数据库驱动实现了XA数据库驱动的效果，具体这个以后再写文章。这里连接池的配置按照上面的文档配置即可。
这里DAO层因为两个数据库所以配置了两个。在Service层可以选择一起注入或者单个注入。
下面配置事务
<bean id="jotm" class="com.sy.utils.JotmFactoryBean"/>
<bean id="jtaTransactionManager" class="org.springframework.transaction.jta.JtaTransactionManager">
<property name="userTransaction" ref="jotm" />
</bean>
<tx:advice id="txAdvice" transaction-manager="jtaTransactionManager">
<tx:attributes>
<!-- 传播行为 -->
<tx:method name="save*" propagation="REQUIRED" rollback-for="com.sy.exceptions.MyException"/>
<tx:method name="insert*" propagation="REQUIRED" rollback-for="com.sy.exceptions.MyException"/>
<tx:method name="add*" propagation="REQUIRED" rollback-for="com.sy.exceptions.MyException"/>
<tx:method name="create*" propagation="REQUIRED" rollback-for="com.sy.exceptions.MyException"/>
<tx:method name="delete*" propagation="REQUIRED" rollback-for="com.sy.exceptions.MyException"/>
<tx:method name="update*" propagation="REQUIRED" rollback-for="com.sy.exceptions.MyException"/>
<tx:method name="find*" propagation="SUPPORTS" read-only="true" />
<tx:method name="select*" propagation="SUPPORTS" read-only="true" />
<tx:method name="get*" propagation="SUPPORTS" read-only="true" />
</tx:attributes>
</tx:advice>
<!-- 切面 -->
<aop:config expose-proxy="true">
<aop:pointcut id="bussinessService" expression="execution(* com.sy.service.*.*(..))" />
<aop:advisor pointcut-ref="bussinessService" advice-ref="txAdvice"/>
</aop:config>
<tx:annotation-driven transaction-manager="jtaTransactionManager"/>
com.sy.utils.JotmFactoryBean需要手动实现，因为spring4.x不在提供JtaTransactionManager 的默认实现。
到这里JTA分布式事务的配置已经完成，下面我们看看Service层，和junit测试
@Service
public class CommonServiceImpl implements CommonService{
/** serialVersionUID*/
private static final long serialVersionUID = -5991777455696969065L;
@Resource
private CommonDao commonDao;
@Resource
private CommonDao commonDao2;
//测试两个数据库的事务
@Override
public void saveTest() throws MyException {
commonDao.update("update Dictionary set name=? where id=? ", new Value().add("货主类型").add(1l).getParams());
commonDao2.update("delete Member where id>25");
int i = 1/0; //这里异常，前面配置正确的话事务会回滚
}
}
因为这是一个公共的Service层，需要操作两个数据库，所以两个DAO一起注入。下面是Junit测试代码
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = {"classpath:spring/applicationContext-*.xml"})
public class TestSupport extends AbstractJUnit4SpringContextTests {
@Autowired
private CommonService commonService;
@Test
public void save() throws MyException{
commonService.saveTest();
}
public CommonService getCommonService() {
return commonService;
}
public void setCommonService(CommonService commonService) {
this.commonService = commonService;
}
}
运行结果如我们所料，事务回滚，OK！
下面是直接配置的方式，这种方式是一个老同事那边看到的。当时惊呼不用jta也能实现跨库事务啊。跟普通的单数据库项目配置一样，只是DataSource，SessionFactory，transactionmanager等都是两个。下面是配置
<!-- 数据库连接池 -->
<bean id="dataSource1" class="com.alibaba.druid.pool.DruidDataSource"
destroy-method="close">
<property name="url" value="${jdbc.url}" />
<property name="username" value="${jdbc.username}" />
<property name="password" value="${jdbc.password}" />
<property name="driverClassName" value="${jdbc.driver}" />
<property name="maxActive" value="${jdbc.maxActive}" />
<property name="minIdle" value="${jdbc.minIdle}" />
</bean>
<bean id="dataSource2" class="com.alibaba.druid.pool.DruidDataSource"
destroy-method="close">
<property name="url" value="${jdbc2.url}" />
<property name="username" value="${jdbc2.username}" />
<property name="password" value="${jdbc2.password}" />
<property name="driverClassName" value="${jdbc2.driver}" />
<property name="maxActive" value="${jdbc2.maxActive}" />
<property name="minIdle" value="${jdbc2.minIdle}" />
</bean>
<bean id="sessionFactory1"
class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
<property name="dataSource" ref="dataSource1" />
<property name="packagesToScan">
<list>
<value>com.sy.domain</value>
</list>
</property>
<property name="hibernateProperties">
<props>
<prop key="hibernate.dialect">
org.hibernate.dialect.OracleDialect
</prop>
<prop key="hibernate.show_sql">true</prop>
<prop key="hibernate.autoReconnect">true</prop>
<!-- <prop key="hibernate.hbm2ddl.auto">update</prop> -->
</props>
</property>
</bean>
<bean id="sessionFactory2"
class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
<property name="dataSource" ref="dataSource2" />
<property name="packagesToScan">
<list>
<value>com.sy.domain</value>
</list>
</property>
<property name="hibernateProperties">
<props>
<prop key="hibernate.dialect">
org.hibernate.dialect.SQLServerDialect
</prop>
<prop key="hibernate.show_sql">true</prop>
<prop key="hibernate.autoReconnect">true</prop>
<!-- <prop key="hibernate.hbm2ddl.auto">update</prop> -->
</props>
</property>
</bean>
<bean id="commonDao" class="com.sy.dao.impl.CommonDaoImpl" >
<property name="sessionFactory" ref="sessionFactory1"/>
</bean>
<bean id="commonDao2" class="com.sy.dao.impl.CommonDaoImpl" >
<property name="sessionFactory" ref="sessionFactory2"/>
</bean>
<bean id="transactionManager1" class="org.springframework.orm.hibernate4.HibernateTransactionManager">
<property name="sessionFactory" ref="sessionFactory1" />
</bean>
<bean id="transactionManager2" class="org.springframework.orm.hibernate4.HibernateTransactionManager">
<property name="sessionFactory" ref="sessionFactory2" />
</bean>
<tx:advice id="txAdvice1" transaction-manager="transactionManager1">
<tx:attributes>
<!-- 传播行为 -->
<tx:method name="save*" propagation="REQUIRED" rollback-for="com.sy.exceptions.MyException"/>
<tx:method name="insert*" propagation="REQUIRED" rollback-for="com.sy.exceptions.MyException"/>
<tx:method name="add*" propagation="REQUIRED" rollback-for="com.sy.exceptions.MyException"/>
<tx:method name="create*" propagation="REQUIRED" rollback-for="com.sy.exceptions.MyException"/>
<tx:method name="delete*" propagation="REQUIRED" rollback-for="com.sy.exceptions.MyException"/>
<tx:method name="update*" propagation="REQUIRED" rollback-for="com.sy.exceptions.MyException"/>
<tx:method name="find*" propagation="SUPPORTS" read-only="true" />
<tx:method name="select*" propagation="SUPPORTS" read-only="true" />
<tx:method name="get*" propagation="SUPPORTS" read-only="true" />
</tx:attributes>
</tx:advice>
<tx:advice id="txAdvice2" transaction-manager="transactionManager2">
<tx:attributes>
<!-- 传播行为 -->
<tx:method name="save*" propagation="REQUIRED" rollback-for="com.sy.exceptions.MyException"/>
<tx:method name="insert*" propagation="REQUIRED" rollback-for="com.sy.exceptions.MyException"/>
<tx:method name="add*" propagation="REQUIRED" rollback-for="com.sy.exceptions.MyException"/>
<tx:method name="create*" propagation="REQUIRED" rollback-for="com.sy.exceptions.MyException"/>
<tx:method name="delete*" propagation="REQUIRED" rollback-for="com.sy.exceptions.MyException"/>
<tx:method name="update*" propagation="REQUIRED" rollback-for="com.sy.exceptions.MyException"/>
<tx:method name="find*" propagation="SUPPORTS" read-only="true" />
<tx:method name="select*" propagation="SUPPORTS" read-only="true" />
<tx:method name="get*" propagation="SUPPORTS" read-only="true" />
</tx:attributes>
</tx:advice>
<!-- 切面 -->
<aop:config expose-proxy="true">
<aop:pointcut id="bussinessService1" expression="execution(* com.sy.service.*.*(..))" />
<aop:advisor pointcut-ref="bussinessService1" advice-ref="txAdvice1"/>
</aop:config>
<aop:config expose-proxy="true">
<aop:pointcut id="bussinessService2" expression="execution(* com.sy.service.*.*(..))" />
<aop:advisor pointcut-ref="bussinessService2" advice-ref="txAdvice2"/>
</aop:config>
这里配置和普通单库配置基本一样，连接池也是自由选择。但是都是两个配置，spring4对多个事务配置也是支持的。测试代码和上面JTA配置的一样，不再给出。