spring mybatis mapper接口注解方式注入

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最近做项目使用mybatis-generator生成mybatis的mapper.xml映射文件和mapper接口。
原来采用spring-bean的方式显示注入，代码如下：

<bean id="articleMapper" class="org.mybatis.spring.mapper.MapperFactoryBean">    <property name="mapperInterface" value="com.kuanrf.gs.article.dao.ArticleMapper" />    <property name="sqlSessionFactory" ref="sqlSessionFactory" /></bean>

发现每个mybatis的mapper接口都这么配置的话，太麻烦。现优化采用spring统一扫描自动注入。
application_spring_db.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:tx="http://www.springframework.org/schema/tx"      xsi:schemaLocation="http://www.springframework.org/schema/beans             http://www.springframework.org/schema/beans/spring-beans-4.2.xsd             http://www.springframework.org/schema/tx             http://www.springframework.org/schema/tx/spring-tx-4.2.xsd">      <!-- 配置dbcp数据源 -->      <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource" destroy-method="close">          <property name="driverClass" value="${jdbc.driver}" />          <property name="jdbcUrl" value="${jdbc.url}" />          <property name="user" value="${jdbc.username}" />          <property name="password" value="${jdbc.password}" />          <property name="initialPoolSize" value="${connection_pools.initial_pool_size}" />        <property name="minPoolSize" value="${connection_pools.min_pool_size}" />        <property name="maxPoolSize" value="${connection_pools.max_pool_size}" />        <property name="maxIdleTime" value="${connection_pools.max_idle_time}" />        <property name="acquireIncrement" value="${connection_pools.acquire_increment}" />        <property name="checkoutTimeout" value="${connection_pools.checkout_timeout}" />    </bean>      <!-- 配置mybatisSqlSessionFactoryBean -->      <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">          <property name="dataSource" ref="dataSource" />          <property name="configLocation" value="classpath:mybatis/mybatis.xml"/>          <property name="mapperLocations" value="classpath*:com/itclj/magpie/**/*Mapper.xml"/>    </bean>      <!-- 配置SqlSessionTemplate -->      <bean id="sqlSessionTemplate" class="org.mybatis.spring.SqlSessionTemplate">          <constructor-arg name="sqlSessionFactory" ref="sqlSessionFactory" />      </bean>      <!-- 配置mybatis mapper接口 -->    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">        <property name="basePackage" value="com.itclj.magpie.**.dao"/>        <property name="sqlSessionTemplateBeanName" value="sqlSessionTemplate"/>    </bean>    <!-- 事务配置 -->      <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">          <property name="dataSource" ref="dataSource" />      </bean>      <!-- 使用annotation注解方式配置事务 -->      <tx:annotation-driven transaction-manager="transactionManager"/>  </beans>

其中如下代码为spring自扫描所有dao包并把其下的所有mybatis接口文件装配入容器。

<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">        <property name="basePackage" value="com.itclj.magpie.**.dao"/>        <property name="sqlSessionTemplateBeanName" value="sqlSessionTemplate"/></bean>

mybatis接口mapper需要加@Repository注解，方可直接在Service层直接自动装配注入。
mybatis接口mapper举例如下：

@Repositorypublic interface UserBeanMapper extends BaseMapper<UserBean,UserBeanExample,Long> {}

Service层注入mybatis接口mapper的时候需要在构造方法中注入，这样注入mapper实例才不会空。

@Service(value = "userService")public class UserServiceImpl extends BaseServiceImpl<UserBean, UserBeanExample, Long> implements UserService {    @Autowired()    public UserServiceImpl(UserBeanMapper userBeanMapper) {        this.setMapper(userBeanMapper);    }}

工程目录结构如下图

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