Spring+Mybatis之多數據源配置

同一applicationContext.xml中：

1，配置多個數據源(採用連接池c3p0，直接jdbc連也行)

數據源1：dataSource1

<bean id = "dataSource1" class= "com.mchange.v2.c3p0.ComboPooledDataSource" lazy-init = "default">

<property name="driverClass" value = ""/>

...

...

</bean>

數據源2：dataSource2

<bean id = "dataSource2" class= "com.mchange.v2.c3p0.ComboPooledDataSource" lazy-init = "default">

<property name="driverClass" value = ""/>

...

...

</bean>

2, 配置mybatis數據會話管理（sqlSessionFactoryBean）

會話factory1：sqlSessionFactoryBean1

<bean id = "sqlSessionFactoryBean1" class = "mybatis.spring.SqlSessionFactoryBean">

<property name = "mapperLocations">

<list>

//不同factory，儘量保持其mapper的路徑不同

<value>classpath:mapper/*Mapper.xml</value> //classpath指的是：src/main/resources(maven項目文件包結構哦)

</list>

</property>

<property name = "dataSource" ref = "dataSource1"></property>

</bean>

會話factory2：sqlSessionFactoryBean2

<bean id = "sqlSessionFactoryBean2" class = "mybatis.spring.SqlSessionFactoryBean">

<property name = "mapperLocations">

<list>

<value>classpath:mapper/*Mapper.xml</value> 

</list>

</property>

<property name = "dataSource" ref = "dataSource2"></property>

</bean>

3， 配置Dao接口層（重點注意）

mybatis用mapperScannerConfigurer掃描相關的dao(或mapper)的interface的包，將其注入到spring進行管理；

dao層需要注入第2步配置的sessionFactory來獲得session(session中加入事物等操作)，跟sessionFactory中配置的*Mapper.xml進行一一匹配；

mapperScanner1:

<bean id="mapperScanner1" class="org.mybatis.spring.mapper.MapperScannerConfigurer">

//不同數據源的掃描dao層不要放在一起，不然數據源1掃描了數據源2的dao，那 去數據源1的mappe.xml中匹配時，會找不到相應方法，而報錯！！！

<property name = "basePackage" value = "com.business.*.*dao1"/> 

//配置dao層需注入的sessionFactory

<property name = "sqlSessionFactoryBeanName" value = "sqlSessionFactoryBean1"/>

</bean>

mapperScanner2:

<bean id="mapperScanner2" class="org.mybatis.spring.mapper.MapperScannerConfigurer">

<property name = "basePackage" value = "com.business.*.*dao2"/> 

<property name = "sqlSessionFactoryBeanName" value = "sqlSessionFactoryBean2"/>

</bean>

其他配置：事物配置（dataSourceTransactionManager）,持久化模板（SqlSessionTemplate）

常見錯誤1：

No unique bean of type [org.apache.ibatis.sessioin.SqlSessionFactory] is defined:expected single matching bean but found 2:[sqlSessionFactoryBean1,sqlSessionFactoryBean2]

解決問題：檢查步驟3配置，是否有配置sqlSessionFactoryBeanName

常見錯誤2：

...Dao conflicts with existing, non-compatible bean definition of same name and class[org.mybatis.spring.mapper.MapperFactoryBean]

解決問題：檢查步驟3配置，屬性basePackage，兩個數據源是否掃描了同一dao層包，若是，更改dao層包，不同數據源需掃描不同的dao層包。

參考：http://stackoverflow.com/questions/4746766/spring-and-mybatis-multiple-data-sources-setup