关于Spring+MyBatis的多数据源切换

因业务需求，需要连接到两个数据库进行切换，整理了一下Spring+MyBatis的多数据源切换.
先上applicationContext.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns=""
    xmlns:xsi="" xmlns:context=""
    xmlns:jee="" xmlns:tx=""
    xmlns:aop="" xmlns:p=""
    xmlns:util=""
    xsi:schemaLocation=" /spring-beans-3.0.xsd
                 /spring-context-3.0.xsd
                 /spring-tx-3.0.xsd
                 /spring-jee-3.0.xsd
                 /spring-aop-3.0.xsd  /spring-util-3.0.xsd"
    default-autowire="byName">
    <!-- <context:property-placeholder order="1" location="classpath:jdbc.properties" /> -->
    <util:properties id="dataSourceProps" location="classpath:jdbc.properties"/>

    <context:component-scan base-package="com.cares" />
    <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource"
        destroy-method="close">
        <property name="driverClass" value="#{dataSourceProps['com.cares.baseframe.c3p0.driverClass']}" />
        <property name="jdbcUrl" value="#{dataSourceProps['com.cares.baseframe.c3p0.jdbcUrl']}" />
        <property name="user" value="#{dataSourceProps['com.cares.baseframe.c3p0.user']}" />
        <property name="password" value="#{dataSourceProps['com.cares.baseframe.c3p0.password']}" />
        <property name="minPoolSize" value="#{dataSourceProps['com.cares.baseframe.c3p0.minPoolSize']}" />
        <property name="maxPoolSize" value="#{dataSourceProps['com.cares.baseframe.c3p0.maxPoolSize']}" />
        <property name="initialPoolSize" value="#{dataSourceProps['com.cares.baseframe.c3p0.initialPoolSize']}" />
        <property name="maxIdleTime" value="#{dataSourceProps['com.cares.baseframe.c3p0.maxIdleTime']}" />
        <property name="acquireIncrement" value="#{dataSourceProps['com.cares.baseframe.c3p0.acquireIncrement']}" />
        <property name="maxStatements" value="#{dataSourceProps['com.cares.baseframe.c3p0.maxStatements']}" />
        <property name="maxStatementsPerConnection"
            value="#{dataSourceProps['com.cares.baseframe.c3p0.maxStatementsPerConnection']}" />
        <property name="idleConnectionTestPeriod"
            value="#{dataSourceProps['com.cares.baseframe.c3p0.idleConnectionTestPeriod']}" />
        <property name="acquireRetryAttempts"
            value="#{dataSourceProps['com.cares.baseframe.c3p0.acquireRetryAttempts']}" />
        <property name="breakAfterAcquireFailure"
            value="#{dataSourceProps['com.cares.baseframe.c3p0.breakAfterAcquireFailure']}" />
        <property name="testConnectionOnCheckout"
            value="#{dataSourceProps['com.cares.baseframe.c3p0.testConnectionOnCheckout']}" />
    </bean>


     <bean id="hccDataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource" destroy-method="close">
       <property name="driverClass" value="#{dataSourceProps['com.cares.hcc.c3p0.driverClass']}" />
        <property name="jdbcUrl" value="#{dataSourceProps['com.cares.hcc.c3p0.jdbcUrl']}" />
        <property name="user" value="#{dataSourceProps['com.cares.hcc.c3p0.user']}" />
        <property name="password" value="#{dataSourceProps['com.cares.hcc.c3p0.password']}" />
        <property name="minPoolSize" value="#{dataSourceProps['com.cares.hcc.c3p0.minPoolSize']}" />
        <property name="maxPoolSize" value="#{dataSourceProps['com.cares.hcc.c3p0.maxPoolSize']}" />
        <property name="initialPoolSize" value="#{dataSourceProps['com.cares.hcc.c3p0.initialPoolSize']}" />
        <property name="maxIdleTime" value="#{dataSourceProps['com.cares.hcc.c3p0.maxIdleTime']}" />
        <property name="acquireIncrement" value="#{dataSourceProps['com.cares.hcc.c3p0.acquireIncrement']}" />
        <property name="maxStatements" value="#{dataSourceProps['com.cares.hcc.c3p0.maxStatements']}" />
        <property name="maxStatementsPerConnection"
            value="#{dataSourceProps['com.cares.hcc.c3p0.maxStatementsPerConnection']}" />
        <property name="idleConnectionTestPeriod"
            value="#{dataSourceProps['com.cares.hcc.c3p0.idleConnectionTestPeriod']}" />
        <property name="acquireRetryAttempts"
            value="#{dataSourceProps['com.cares.hcc.c3p0.acquireRetryAttempts']}" />
        <property name="breakAfterAcquireFailure"
            value="#{dataSourceProps['com.cares.hcc.c3p0.breakAfterAcquireFailure']}" />
        <property name="testConnectionOnCheckout"
            value="#{dataSourceProps['com.cares.hcc.c3p0.testConnectionOnCheckout']}" />
    </bean>


     <bean id="myDataSource" class="com.cares.baseframe.MultipleDataSource">
        <property name="targetDataSources">
            <map key-type="java.lang.String">
                <entry value-ref="dataSource" key="my"></entry>
                <entry value-ref="hccDataSource" key="hcc"></entry>
            </map>
        </property>
        <property name="defaultTargetDataSource" ref="dataSource"></property>
    </bean>

    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="configLocation" value="classpath:mybatis-config.xml"></property>
        <property name="dataSource">
            <ref bean="myDataSource" />
        </property>
        <property name="mapperLocations" value="classpath:com/cares/*/*/mapping/*.xml" />
        <property name="typeAliasesPackage" value="com.cares" />
    </bean>
    <bean id="transactionManager"
        class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
        <property name="dataSource" ref="myDataSource" />
    </bean>
    <bean class="org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor" />

    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
           <property name="basePackage" value="com.cares.*.*.dao" />
           <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory" />
    </bean>

     <bean id="sqlSession" class="org.mybatis.spring.SqlSessionTemplate">
        <constructor-arg index="0" ref="sqlSessionFactory" />
    </bean>

    <!-- import spring timer configuration file
    <import resource="classpath:timer.xml"/>
    -->

    <!-- import MyBatis configuration file
    <import resource="classpath:mybatisContext.xml"/>-->

    <tx:advice id="webAdvice" transaction-manager="transactionManager">
        <tx:attributes>
            <tx:method name="do*" propagation="REQUIRED" read-only="false" rollback-for="Throwable"/>
            <tx:method name="query*" propagation="REQUIRED" read-only="true" />
            <tx:method name="find*" propagation="REQUIRED" read-only="true" />
            <tx:method name="select*" propagation="REQUIRED" read-only="true" />
        </tx:attributes>
    </tx:advice>
    <aop:aspectj-autoproxy proxy-target-class="true"></aop:aspectj-autoproxy>
    <bean id="controllerAop" class="com.cares.baseframe.aop.ControllerAop" />
    <aop:config>
        <aop:aspect ref="controllerAop">
            <aop:pointcut id="actionDo"
                expression="execution(* com.cares.*.*.controller.*Controller.do*())" />
            <aop:around pointcut-ref="actionDo" method="aroundDo" />
        </aop:aspect>
        <aop:aspect ref="controllerAop">
            <aop:pointcut id="actionQuery"
                expression="execution(* com.cares.*.*.controller.*Controller.query*())" />
            <aop:around pointcut-ref="actionQuery" method="aroundQuery" />
        </aop:aspect>
        <aop:aspect ref="controllerAop">
            <aop:pointcut id="actionFind"
                expression="execution(* com.cares.*.*.controller.*Controller.find*())" />
            <aop:around pointcut-ref="actionFind" method="aroundFind" />
        </aop:aspect>
    </aop:config>
    <aop:config>
        <aop:pointcut id="allAdvice"
            expression="execution(* com.cares.*.*.service.*.*(..))" />
        <aop:advisor advice-ref="webAdvice" pointcut-ref="allAdvice" />
    </aop:config>

    <!-- <import resource="classpath:applicationContext-base.xml"/> -->
</beans>

具体为配置了两个数据源dataSource和hccDataSource，用myDataSource将两个数据源合并，并设置相应键值和默认数据源dataSource
其他工厂类和事务管理的配置不变。
注：因为在service配置了事务一致性，导致在service不能切换数据源，只能在controller层进行切换。

附上相对应切换数据源的MultipleDataSource类代码

package com.cares.baseframe;

import java.util.Map;

import org.springframework.jdbc.datasource.lookup.AbstractRoutingDataSource;

public class MultipleDataSource extends AbstractRoutingDataSource {
    private static final ThreadLocal<String> dataSourceKey = new InheritableThreadLocal<String>();

    public static void setDataSourceKey(String dataSource) {
        dataSourceKey.set(dataSource);
    }

    @Override
    protected Object determineCurrentLookupKey() {
        return dataSourceKey.get();
    }

    @Override
    public void setTargetDataSources(Map<Object, Object> targetDataSources) {
        super.setTargetDataSources(targetDataSources);
    }

    public static void clear(){
        dataSourceKey.remove();
    }
}

常量类DataSourceInstances

package com.cares.baseframe;

public class DataSourceInstances{
    public static final String MYDATA="my";
    public static final String HCCDATA="hcc";
}

具体手动切换数据源方法
MultipleDataSource.setDataSourceKey(DataSourceInstances.MYDATA);
MultipleDataSource.setDataSourceKey(DataSourceInstances.HCCDATA);


如果没有配置service层的事务，可以选用自动切换，需要用到拦截器Interceptor
具体在application.xml配置上加上application-base.xml 如下

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns=""
    xmlns:xsi=""
    xmlns:aop=""
    xmlns:util=""
    xmlns:context=""
    xsi:schemaLocation=" /spring-beans-3.2.xsd
     /spring-util-3.2.xsd
     /spring-aop-3.2.xsd
     /spring-context-3.2.xsd">

    <context:component-scan base-package="com.cares.*.*.dao"/>
    <context:component-scan base-package="com.cares.*.*.service.impl"/>
     <context:component-scan base-package="com.hoo.*.interceptor"/>

    <!-- 启用Aop AspectJ注解 -->
    <aop:aspectj-autoproxy/>






    <!-- 配置一个拦截器对象，处理具体的切换数据源的业务 -->
    <bean id="dataSourceMethodInterceptor" class="com.cares.baseframe.DataSourceMethodInterceptor"/>

    <!-- 参与动态切换数据源的切入点对象 (切入点对象，确定何时何地调用拦截器) -->
    <bean id="methodCachePointCut" class="org.springframework.aop.support.RegexpMethodPointcutAdvisor">
        <!-- 配置缓存aop切面 -->
        <property name="advice" ref="dataSourceMethodInterceptor" />
        <!-- 配置哪些方法参与缓存策略 -->
        <!--
            .表示符合任何单一字元
            ### +表示符合前一个字元一次或多次
            ### *表示符合前一个字元零次或多次
            ###  \Escape任何Regular expression使用到的符号
        -->
        <!-- .*表示前面的前缀(包括包名) 表示print方法-->
        <property name="patterns">
            <list>
                <value>com.cares.*.*.service.impl.*Service*\.*.*</value>
                 <value>com.cares.*.*.mapper.*Mapper*\.*.*</value>
            </list>
        </property>
    </bean>
</beans>

附上拦截器代码DataSourceMethodInterceptor

package com.cares.baseframe;

import java.lang.reflect.Proxy;

import org.aopalliance.intercept.MethodInterceptor;
import org.aopalliance.intercept.MethodInvocation;
import org.apache.commons.lang.ClassUtils;
import org.springframework.beans.factory.InitializingBean;

/**
 *
 */
public class DataSourceMethodInterceptor implements MethodInterceptor, InitializingBean {

    @Override
    public Object invoke(MethodInvocation invocation) throws Throwable {
        Class<?> clazz = invocation.getThis().getClass();
        String className = clazz.getName();
        if (ClassUtils.isAssignable(clazz, Proxy.class)) {
            className = invocation.getMethod().getDeclaringClass().getName();
        }
        String methodName = invocation.getMethod().getName();
        Object[] arguments = invocation.getArguments();

        if (className.contains("Hcc")) {
            MultipleDataSource.setDataSourceKey("hcc");
        }else{
            MultipleDataSource.setDataSourceKey(DataSourceInstances.MYDATA);
        }

        Object result = invocation.proceed();
        return result;
    }

    @Override
    public void afterPropertiesSet() throws Exception {
//        log.trace("afterPropertiesSet……");
    }
}