背景：
鑑於兩個資料來源彼此獨立，沒有動態切換庫的現象，所以一般不存在跨資料來源的事務問題，此處只是簡單的複製一份新的資料來源配置，dao層應用新的SqlMapClientTemplate，為了結構清晰，兩個資料來源的SqlMap配置和dao配置獨立開來，具體程式碼如下：

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: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/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"
 
>
<bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
      <property name="locations">
         <list>
            <value>classpath:jdbc.properties</value>
         </list>
      </property>
</bean>
<bean id="dataSource"
 
 class="org.apache.commons.dbcp.BasicDataSource"
destroy-method="close">
      <property name="driverClassName" value="${jdbc.driver}">
      </property>
      <property name="url" value="${jdbc.url}"></property>
      <property name="username" value="${jdbc.username}"></property>
      <property name="password" value="${jdbc.password}"></property>
      <property name="initialSize" value="${pool.initialSize}"></property>
      <property name="maxActive" value="${pool.maxActive}"></property>
      <property name="maxIdle" value="${pool.maxIdle}"></property>
      <property name="maxWait" value="${pool.maxWait}"></property>
</bean>
<!-- 配置ibatis -->
<bean id="sqlMapClient" class="org.springframework.orm.ibatis.SqlMapClientFactoryBean">
      <property name="dataSource">
         <ref local="dataSource" />
      </property>
      <property name="configLocation">
         <value>classpath:SqlMapConfig.xml</value>
      </property>
</bean>
<!-- 事務配置 -->
<bean id="transactionManager"
class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
      <property name="dataSource" ref="dataSource" />
   </bean>
   <tx:advice id="txAdvice" transaction-manager="transactionManager">
      <tx:attributes>
         <tx:method name="save*" propagation="REQUIRED"
rollback-for="com.maifanfan.common.ServiceException" />
         <tx:method name="del*" propagation="REQUIRED"
rollback-for="com.maifanfan.common.ServiceException" />
         <tx:method name="update*" propagation="REQUIRED"
rollback-for="com.maifanfan.common.ServiceException" />
<!-- <tx:method name="*" read-only="true" /> -->
      </tx:attributes>
</tx:advice>
<aop:config>
      <aop:pointcut id="allManagerMethod"
expression="execution(* com.tom.hss.service.impl.*.*(..))"></aop:pointcut>
      <aop:advisor advice-ref="txAdvice"
pointcut-ref="allManagerMethod"></aop:advisor>
   </aop:config>
<!--   
      <aop:config proxy-target-class="true">
      <aop:advisor pointcut="execution(* com.service.*.*(..))"
      advice-ref="txAdvice" />
      </aop:config>
   -->
   <!-- jdbc連線 -->
<bean id="jdbcTemplate"
class="org.springframework.jdbc.core.JdbcTemplate">
      <property name="dataSource">
         <ref bean="dataSource" />
      </property>
</bean>
<!-- ibatis連線 -->
<bean id="sqlMapClientTemplate"
class="org.springframework.orm.ibatis.SqlMapClientTemplate">
      <property name="sqlMapClient">
         <ref bean="sqlMapClient" />
      </property>
</bean>
<!-- 第二個資料來源配置，此處複製一份上面的配置，id標識為2-->
<bean id="dataSource2"
class="org.apache.commons.dbcp.BasicDataSource"
destroy-method="close">
      <property name="driverClassName" value="oracle.jdbc.driver.OracleDriver">
      </property>
      <property name="url" value="jdbc:oracle:thin:@10.7.70.216:1521:abpdb"></property>
      <property name="username" value="abpkftest"></property>
      <property name="password" value="abpkftest"></property>
      <property name="initialSize" value="${pool.initialSize}"></property>
      <property name="maxActive" value="${pool.maxActive}"></property>
      <property name="maxIdle" value="${pool.maxIdle}"></property>
      <property name="maxWait" value="${pool.maxWait}"></property>
</bean>
<bean id="sqlMapClient2" class="org.springframework.orm.ibatis.SqlMapClientFactoryBean">
      <property name="dataSource">
         <ref local="dataSource2" />
      </property>
      <property name="configLocation">
         <value>classpath:SqlMapConfig2.xml</value>
      </property>
</bean>
<!-- ibatis連線 -->
<bean id="sqlMapClientTemplate2" class="org.springframework.orm.ibatis.SqlMapClientTemplate">
      <property name="sqlMapClient">
         <ref bean="sqlMapClient2" />
      </property>
</bean>
   <!--第二份事務配置-->
<bean id="transactionManager2" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
      <property name="dataSource" ref="dataSource2" />
</bean>
<tx:advice id="txAdvice2" transaction-manager="transactionManager">
      <tx:attributes>
         <tx:method name="save*" propagation="REQUIRED"
rollback-for="com.maifanfan.common.ServiceException" />
         <tx:method name="del*" propagation="REQUIRED"
rollback-for="com.maifanfan.common.ServiceException" />
         <tx:method name="update*" propagation="REQUIRED"
rollback-for="com.maifanfan.common.ServiceException" />
<!-- <tx:method name="*" read-only="true" /> -->
     </tx:attributes>
</tx:advice>
   <!--aop-->
<aop:config>
      <aop:pointcut id="allManagerMethod2"
expression="execution(* com.tom.hss.service.impl.*.*(..))"></aop:pointcut>
      <aop:advisor advice-ref="txAdvice2"
pointcut-ref="allManagerMethod2"></aop:advisor>
</aop:config>
</beans>

sqlMapConfig2.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE sqlMapConfig
        PUBLIC "-//iBATIS.com//DTD SQL Map Config 2.0//EN"
        "http://www.ibatis.com/dtd/sql-map-config-2.dtd">
<sqlMapConfig>
    <settings useStatementNamespaces="true" />
    <sqlMap resource="com/tom/bean/sqlmap/TB_CUST_SqlMap.xml" />
    <sqlMap resource="com/tom/bean/sqlmap/TB_TASK_SqlMap.xml" />
</sqlMapConfig>

applicationContext_dao2.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: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/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">
<!--新增需求 處理結果查詢dao-->
<bean id="bssCustDAO" class="com.tom.dao.impl.BssCustDAOImpl">
         <property name="sqlMapClientTemplate" ref="sqlMapClientTemplate2">
         </property>
</bean>
<bean id="bssTaskDAO" class="com.tom.dao.impl.BssTaskDAOImpl">
         <property name="sqlMapClientTemplate" ref="sqlMapClientTemplate2">
         </property>
</bean>
</beans>

說明：
在dao層，daoImpl除了實現dao介面(ibatis要求必須要有介面和實現類)，還繼承了SqlMapClientDaoSupport，通過spring將SqlMapClientTemplate注入到SqlMapClientDaoSupport中，以便在dao中可以getSqlMapClientTemplate，獲取到這個Template從而可以query和execute。
這是ibatis與spring結合的一種做法。

後面針對更復雜的多資料來源動態切換和分散式事務問題，還有進一步的討論。

thanks