Spring分布式事务在service中无法动态切换数据源

[hi_kevin]

Spring分布式事务在service中无法切换数据源
项目采用的是struts2+spring+ibatis架构，下面是关键部分代码：

applicationContext.xml：

<?xml version="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/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" 
		   default-autowire="byName" default-lazy-init="false">
    
	<context:component-scan base-package="com.ssi.*" />
	<!-- 属性文件读入 -->
	<bean id="propertyConfigurer" class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
		<property name="locations">
			<list>
				<value>classpath*:jdbc.properties</value>
			</list>
		</property>
	</bean>
	<!-- JTA 数据源配置 -->
	<bean id="center" class="com.atomikos.jdbc.AtomikosDataSourceBean" init-method="init" destroy-method="close">
		<property name="uniqueResourceName">
			<value>mysql/center</value>
		</property>
		<property name="xaDataSourceClassName">
			<value>${jta.driver.className}</value>
		</property>
		<property name="xaProperties">
			<props>
				<prop key="url">${center.jdbc.driver.url}</prop>
				<prop key="user">${center.sql.user.name}</prop>
				<prop key="password">${center.sql.user.password}</prop>
			</props>
		</property>
		<property name="testQuery" value="select 1" />
		<property name="poolSize">
			<value>${poolsize}</value>
		</property>
		<property name="maxPoolSize">
			<value>${maxPoolSize}</value>
		</property>
		<property name="borrowConnectionTimeout"><value>${borrowConnectionTimeout}</value></property>
	</bean>
	
	<bean id="db1" class="com.atomikos.jdbc.AtomikosDataSourceBean" init-method="init" destroy-method="close">
		<property name="uniqueResourceName">
			<value>mysql/db1</value>
		</property>
		<property name="xaDataSourceClassName">
			<value>${jta.driver.className}</value>
		</property>
		<property name="xaProperties">
			<props>
				<prop key="url">${db1.jdbc.driver.url}</prop>
				<prop key="user">${company.sql.user.name}</prop>
				<prop key="password">${company.sql.user.password}</prop>
			</props>
		</property>
		<property name="testQuery" value="select 1" />
		<property name="poolSize">
			<value>${poolsize}</value>
		</property>
		<property name="maxPoolSize">
			<value>${maxPoolSize}</value>
		</property>
		<property name="borrowConnectionTimeout"><value>${borrowConnectionTimeout}</value></property>
	</bean>
	<bean id="db2" class="com.atomikos.jdbc.AtomikosDataSourceBean" init-method="init" destroy-method="close">
		<property name="uniqueResourceName">
			<value>mysql/db2</value>
		</property>
		<property name="xaDataSourceClassName">
			<value>${jta.driver.className}</value>
		</property>
		<property name="xaProperties">
			<props>
				<prop key="url">${db2.jdbc.driver.url}</prop>
				<prop key="user">${company.sql.user.name}</prop>
				<prop key="password">${company.sql.user.password}</prop>
			</props>
		</property>
		<property name="testQuery" value="select 1" />
		<property name="poolSize">
			<value>${poolsize}</value>
		</property>
		<property name="maxPoolSize">
			<value>${maxPoolSize}</value>
		</property>
		<property name="borrowConnectionTimeout"><value>${borrowConnectionTimeout}</value></property>
	</bean>
	
	<bean id="dataSource" class="com.ssi.datasource.DynamicDataSource">
		<property name="targetDataSources">
			<map key-type="java.lang.String">
				<entry key="db1" value-ref="db1" />
				<entry key="db2" value-ref="db2" />
				<entry key="center" value-ref="center" />
			</map>
		</property>
		<property name="defaultTargetDataSource" ref="center" />
	</bean>
	
<!-- 配置sqlMapclient -->
	<bean id="sqlMapClient" class="org.springframework.orm.ibatis.SqlMapClientFactoryBean">
		<property name="configLocation" value="classpath:ibatis-sqlmap-config.xml" />
		<property name="dataSource" ref="dataSource" />
	</bean>

 

	<!-- 支持 @AspectJ 标记-->
	<aop:aspectj-autoproxy proxy-target-class="true"/>

	<!-- 配置JTA的事务管理器 -->   
    <bean id="atomikosTransactionManager" class="com.atomikos.icatch.jta.UserTransactionManager"    init-method="init" destroy-method="close">   
        <property name="forceShutdown" value="true" />   
    </bean>   
    <bean id="atomikosUserTransaction" class="com.atomikos.icatch.jta.UserTransactionImp">   
        <property name="transactionTimeout" value="300" />   
    </bean>   
    <bean id="springTransactionManager"  class="org.springframework.transaction.jta.JtaTransactionManager">   
        <property name="transactionManager" ref="atomikosTransactionManager" />   
        <property name="userTransaction" ref="atomikosUserTransaction" />   
    </bean>
	<!-- 配置通知 -->
	<tx:advice id="txAdvice" transaction-manager="springTransactionManager">
		<tx:attributes>
			 <tx:method name="*" rollback-for="Exception,RuntimeException,com.ssi.exception.SystemException" propagation="REQUIRED" />
		</tx:attributes>
	</tx:advice>
	

	
	<!-- 以AspectJ方式 定义 AOP --> 

	<aop:config>
		<aop:advisor pointcut="execution(* com.ssi.service..*Service*.*(..))" advice-ref="txAdvice" />
	</aop:config>
	
</beans>

UserServiceImpl.java：

public class UserServiceImpl implements IUserService {
	@Resource
	private IUserDao userDao;
	public void addUser(User user) throws Exception{
		DbContextHolder.setDbType("db1");   
		userDao.addUser(user);
		DbContextHolder.setDbType("db2");   
		userDao.addUser(user);
		DbContextHolder.setDbType("center");   
		userDao.addUser(user);
	}
	
	public void addUser2(User user,int status)  throws Exception{
		userDao.addUser(user);
		if(status==1){
			System.out.println(1/0);
		}
	}
}

UserDaoImpl.java：

@Repository("userDao")
public class UserDaoImpl extends SqlMapClientDaoSupport implements IUserDao {
	@Override
	public Integer addUser(User user) throws Exception{
		return (Integer) this.getSqlMapClient().insert("User.insert", user);
	}

}

DynamicDataSource.java：

public class DynamicDataSource extends AbstractRoutingDataSource {

	static Logger log = Logger.getLogger(DynamicDataSource.class);

	protected Object determineCurrentLookupKey() {
		return DbContextHolder.getDbType();
	}

}

DbContextHolder.java：

public class DbContextHolder {
	private static final ThreadLocal contextHolder = new ThreadLocal();

	public static void setDbType(String dbType) {
		contextHolder.set(dbType);
	}

	public static String getDbType() {
		return (String) contextHolder.get();
	}

	public static void clearDbType() {
		contextHolder.remove();
	}

}

三个数据库：dbcenter、db1、db2 表结构均相同

脚本：

DROP TABLE IF EXISTS `tb_user`;

CREATE TABLE `tb_user` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `userName` varchar(20) DEFAULT NULL,
  `password` varchar(60) DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

单元测试：

public class JunitTest{  
	public ApplicationContext cxt;
	@Test
	public void init() throws Exception{
		cxt = new ClassPathXmlApplicationContext(new String[] {"applicationContext.xml"});
		testInsertUser1();
		testInsertUser2();
	}
	
	
	private void testInsertUser1() throws Exception{
		IUserService userService = (IUserService)cxt.getBean("userService");
		User user = new User();
		user.setUserName("user1");
		user.setPassword("0");
		userService.addUser(user);
	}
	
	private void testInsertUser2() throws Exception{
		IUserService userService = (IUserService)cxt.getBean("userService");
		User user = new User();
		user.setUserName("user2");
		user.setPassword("0");
		
		DbContextHolder.setDbType("db1");   
		userService.addUser2(user,0);
		DbContextHolder.setDbType("db2");   
		userService.addUser2(user,0);
		DbContextHolder.setDbType("center");   
		userService.addUser2(user,1);
	}
}  

结果：

testInsertUser1中在service方法中切换数据源，结果不会切换，始终都会将数据保存在db1中（不是很明白）

testInsertUser2中在单元测试方法中切换数据源，会切换，但事务不会回滚，即db1和db2会保存成功，db3不会成功（这点会明白：英文事务配置在service中，在单元测试中切换数据源事务不会回滚）


疑问：如何在service方法中动态切换数据源，并且保证事务?

[小丑哥_V5]

要先理解事务,例如你的事务是放在service... 你切换数据库时为了保证事务的完整性,你应该在进入service之前切换掉数据源,因为如果你是在service方法中切换数据源那是不可行的,因为这个时候spring已经打开了一个事务,他会阻止你切换,所以你应在这之前切换,然后进入service方法,这样spring又给你新切换的数据源加上事务了...

[hi_kevin]

引用 1 楼 shadowsick 的回复:

要先理解事务,例如你的事务是放在service... 你切换数据库时为了保证事务的完整性,你应该在进入service之前切换掉数据源,因为如果你是在service方法中切换数据源那是不可行的,因为这个时候spring已经打开了一个事务,他会阻止你切换,所以你应在这之前切换,然后进入service方法,这样spring又给你新切换的数据源加上事务了...

如果外面切换的话就用不上分布式事务了，即db1和db2中插入成功，dbcenter中插入失败，则整个事务就不回滚了

[小丑哥_V5]

可以参考下这个文章 http://blog.csdn.net/boy00fly/article/details/4772066

[Bumpking]

我觉得aop做数据源切换比较靠谱。

[lgl123ok]

不知道楼主这个问题解决了没，我这边也遇到了同样的问题，JOTM已经配置，但是在service中的一个事务中切换数据源失败。麻烦交流下

[pyliuhui]

楼主这个问题解决了吗？同样的问题，google了好几天都没有解决方案啊。

[yxnloveyang]

你好，你的问题解决了吗？

[hi_kevin]

可以参考一下这个 http://blog.csdn.net/hi_kevin/article/details/9839775