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Mybatis 配置

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2023-12-01

Mybatis 配置文件

MyBatis 是支持定制化 SQL、存储过程以及高级映射的优秀的持久层框架。MyBatis 避免了几乎所有的 JDBC 代码和手动设置参数以及获取结果集。MyBatis 可以对配置和原生Map使用简单的 XML 或注解,将接口和 Java 的 POJOs(Plain Old Java Objects,普通的 Java对象)映射成数据库中的记录

mybatis官方中文文档

http://www.mybatis.org/mybatis-3/zh/

引入Mybatis

预准备

创建一个maven的webapp项目, 参考web项目配置


1 . 首先引入mybatis的jar包, 以及mybatis-spring的整合包 .

2 . 引入spring的jar包依赖

修改pom.xml文件 , 添加下面的依赖 :

     <properties>
            <spring.version>4.3.4.RELEASE</spring.version>
            <mybatis.version>3.4.0</mybatis.version>
            <maven.compiler.encoding>UTF-8</maven.compiler.encoding>
            <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     </properties>

     <dependencies>
             <dependency>
                 <groupId>javax.servlet</groupId>
                 <artifactId>javax.servlet-api</artifactId>
                 <version>4.0.0-b02</version>
             </dependency>

             <dependency>
                 <groupId>junit</groupId>
                 <artifactId>junit</artifactId>
                 <version>4.12</version>
             </dependency>

             <!-- spring核心包 -->
             <dependency>
                 <groupId>org.springframework</groupId>
                 <artifactId>spring-core</artifactId>
                 <version>${spring.version}</version>
             </dependency>

             <dependency>
                 <groupId>org.springframework</groupId>
                 <artifactId>spring-web</artifactId>
                 <version>${spring.version}</version>
             </dependency>
             <dependency>
                 <groupId>org.springframework</groupId>
                 <artifactId>spring-oxm</artifactId>
                 <version>${spring.version}</version>
             </dependency>
             <dependency>
                 <groupId>org.springframework</groupId>
                 <artifactId>spring-tx</artifactId>
                 <version>${spring.version}</version>
             </dependency>

             <dependency>
                 <groupId>org.springframework</groupId>
                 <artifactId>spring-jdbc</artifactId>
                 <version>${spring.version}</version>
             </dependency>

             <dependency>
                 <groupId>org.springframework</groupId>
                 <artifactId>spring-webmvc</artifactId>
                 <version>${spring.version}</version>
             </dependency>
             <dependency>
                 <groupId>org.springframework</groupId>
                 <artifactId>spring-aop</artifactId>
                 <version>${spring.version}</version>
             </dependency>

             <dependency>
                 <groupId>org.springframework</groupId>
                 <artifactId>spring-context-support</artifactId>
                 <version>${spring.version}</version>
             </dependency>

             <dependency>
                 <groupId>org.springframework</groupId>
                 <artifactId>spring-test</artifactId>
                 <version>${spring.version}</version>
             </dependency>

             <!-- mybatis核心包 -->
             <dependency>
                 <groupId>org.mybatis</groupId>
                 <artifactId>mybatis</artifactId>
                 <version>${mybatis.version}</version>
             </dependency>
             <!-- mapper/spring包 -->
             <dependency>
                 <groupId>org.mybatis</groupId>
                 <artifactId>mybatis-spring</artifactId>
                 <version>1.3.0</version>
             </dependency>

             <!-- mybatis分页插件依赖 -->
             <dependency>
                 <groupId>com.github.pagehelper</groupId>
                 <artifactId>pagehelper</artifactId>
                 <version>5.0.0</version>
             </dependency>

             <!-- 导入Mysql数据库链接jar包 -->
             <dependency>
                 <groupId>mysql</groupId>
                 <artifactId>mysql-connector-java</artifactId>
                 <version>5.1.30</version>
             </dependency>

             <!-- 阿里数据库数据源 -->
             <dependency>
                 <groupId>com.alibaba</groupId>
                 <artifactId>druid</artifactId>
                 <version>1.0.7</version>
             </dependency>

             <!--JSON 解析-->
             <dependency>
                 <groupId>com.google.code.gson</groupId>
                 <artifactId>gson</artifactId>
                 <version>2.8.0</version>
             </dependency>

             <!--时间插件-->
             <dependency>
                 <groupId>joda-time</groupId>
                 <artifactId>joda-time</artifactId>
                 <version>2.8.1</version>
             </dependency>

             <dependency>
                 <groupId>commons-lang</groupId>
                 <artifactId>commons-lang</artifactId>
                 <version>2.6</version>
             </dependency>
             <dependency>
                 <groupId>commons-io</groupId>
                 <artifactId>commons-io</artifactId>
                 <version>2.4</version>
             </dependency>

         </dependencies>

3 . 创建mybatis-config.xml 文件 , 这个文件主要是存放一些针对于全局的配置 . mybatis-config.xml的配置


<?xml version="1.0" encoding="UTF-8" ?>
 <!DOCTYPE configuration PUBLIC "-//mapper.org//DTD Config 3.0//EN" "http://mybatis.org/dtd/mybatis-3-config.dtd">
 <configuration>

     <settings>
         <!--开启驼峰命名法 Table(create_time) -> Entity(createTime)-->
         <setting name="mapUnderscoreToCamelCase" value="true"/>
     </settings>

     <!-- 这个是我本地的实体类的alias , 可以全局使用 -->
     <typeAliases>
         <typeAlias alias="User" type="com.lemy.spring_mybatis.pojo.UserDo"/>
     </typeAliases>

     <!-- 分页插件 : 插件文档地址 : https://github.com/pagehelper/Mybatis-PageHelper/blob/master/README_zh.md -->
     <plugins>
         <!-- com.github.pagehelper为PageHelper类所在包名 -->
         <plugin interceptor="com.github.pagehelper.PageInterceptor">
             <!-- 使用下面的方式配置参数 -->
             <property name="helperDialect" value="mysql"/>
             <property name="reasonable" value="true"/>
             <property name="supportMethodsArguments" value="true"/>
         </plugin>
     </plugins>
 </configuration>

4 . 配置mybatis的数据源以及相关配置

resources 文件夹下面创建spring 文件夹 ,在 spring 文件夹中创建 datasource.xml , 用于配置数据源


<?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"
        xmlns:context="http://www.springframework.org/schema/context"
        xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">

      <!-- 扫描service -->
     <context:component-scan base-package="com.lemy.spring_mybatis.service" />

     <!-- 1:引入配置文件 -->
     <bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
         <property name="ignoreUnresolvablePlaceholders" value="true" />
         <property name="location" value="classpath:jdbc.properties" />
     </bean>

     <!-- 2 . 配置数据源 -->
     <bean id="stat-filter" class="com.alibaba.druid.filter.stat.StatFilter">
         <property name="slowSqlMillis" value="800" />
         <property name="logSlowSql" value="true" />
     </bean>

     <bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource" init-method="init" destroy-method="close">
         <property name="url" value="${jdbc.url}" />
         <property name="username" value="${jdbc.username}" />
         <property name="password" value="${jdbc.password}" />
         <property name="filters" value="stat" />
         <property name="proxyFilters">
             <list>
                 <ref bean="stat-filter" />
             </list>
         </property>
         <property name="initialSize" value="5" />
         <property name="minIdle" value="5" />
         <property name="maxActive" value="200" />
         <property name="maxWait" value="60000" />
         <property name="timeBetweenEvictionRunsMillis" value="3000" />
         <property name="minEvictableIdleTimeMillis" value="300000" />
         <property name="validationQuery" value="show status like \'%Service_Status%\';" />
         <property name="testWhileIdle" value="true" />
         <property name="testOnBorrow" value="false" />
         <property name="testOnReturn" value="false" />
         <!-- 打开removeAbandoned功能 -->
         <property name="removeAbandoned" value="true" />
         <!-- 600秒,也就是10分钟 -->
         <property name="removeAbandonedTimeout" value="600" />
         <!-- 关闭abanded连接时输出错误日志 -->
         <property name="logAbandoned" value="true" />
     </bean>

     <!-- 3: 配置sqlSessionFactory对象 -->
     <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
         <property name="dataSource" ref="dataSource" />
         <!-- 加载全局配置 -->
         <property name="configLocation" value="classpath:mybatis-config.xml"/>
         <!-- 加载存放sql的xml文件 , 此处可以使用正则匹配文件 , 因为我只有一个文件 , 所以直接写上这个文件的名字 -->
         <property name="mapperLocations" value="classpath*:mybatis/t_user.xml"/>
     </bean>

     <!-- 4:配置扫描mapper层接口, 动态实现mapper层接口 , 注入spring容器 -->
     <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
         <!-- 
         配置需要扫描的DAO的包,
          com.lemy.spring_mybatis.mapper 是存放mapper文件的路径
         -->
         <property name="basePackage" value="com.lemy.spring_mybatis.mapper" />
         <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"/>
     </bean>

     <!-- 5: 事务管理器 -->
     <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
         <property name="dataSource" ref="dataSource" />
     </bean>

     <!-- 使用全注释事务 -->
     <tx:annotation-driven transaction-manager="transactionManager" />

 </beans>

resources 根目录下面 创建 jdbc.properties 配置文件存放mysql的链接配置

 jdbc.url = jdbc:mysql://121.41.170.231:30005/saas_dev?useUnicode=true&characterEncoding=utf8
 jdbc.username = root
 jdbc.password = 2015wjb

5 . 在 resources 下面创建 mybatis 文件夹用于存放sql配置文件 , 然后在 mybatis 文件夹中创建 t_user.xml

<?xml version="1.0" encoding="UTF-8" ?>
  <!DOCTYPE mapper PUBLIC "-//mapper.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
  <mapper namespace="com.lemy.spring_mybatis.mapper.UserMapper">

      <resultMap id="UserResult" type="User">
          <result column="id" property="id" jdbcType="INTEGER"/>
          <result column="userName" property="userName" jdbcType="VARCHAR"/>
          <result column="password" property="password" jdbcType="VARCHAR"/>
          <result column="mobile" property="mobile" jdbcType="VARCHAR"/>
          <result column="tel" property="tel" jdbcType="VARCHAR"/>
          <result column="email" property="email" jdbcType="VARCHAR"/>
      </resultMap>

      <sql id="_userDoColumn">
           u.id, u.userName, u.password, u.mobile, u.tel, u.email
      </sql>

      <select id="queryUserById" parameterType="java.lang.Long" resultMap="UserResult">
          SELECT <include refid="_userDoColumn"/>
          FROM t_user u
          where u.id = #{userId}
      </select>

      <!--查询全公司成员-->
      <select id="queryUserListByCompanyId" parameterType="java.util.HashMap" resultMap="UserResult">
          SELECT
              <include refid="_userDoColumn"/>
          FROM
              t_user u
          WHERE u.company_id = #{companyId}
      </select>
  </mapper>

配置好了之后 , 创建java的Mapper代码 , Mybatis提供了一种可以只创建interface的类就可以映射到xml的功能 , 所以我们只需要创建 UserMapper.java 的interface . 如下图 :


Spring + Mybatis 代码整合

6 . 在 src/main/java 文件夹中创建我们的java代码的目录结构 . 如下图所示 :

创建servicepojo 文件夹 , 分别存放业务层和实体类 . 详细目录如下图所示 :

创建UserService.java 代码如下 :

 package com.lemy.spring_mybatis.service;

 import com.lemy.spring_mybatis.pojo.UserDo;

 import java.util.List;

 /**
  * @author leiniao
  */
 public interface UserService {

     UserDo queryUserById(Long userId);

     List<UserDo> queryUserListByCompanyId(Long companyId);

 }

创建 UserDo.java 实体类 , 代码如下 :

 package com.lemy.spring_mybatis.pojo;

 public class UserDo {
     private Integer id;
     private String userName;
     private String password;
     private String mobile;
     private String tel;
     private String email;

     public Integer getId() {
         return id;
     }

     public void setId(Integer id) {
         this.id = id;
     }

     public String getUserName() {
         return userName;
     }

     public void setUserName(String userName) {
         this.userName = userName;
     }

     public String getPassword() {
         return password;
     }

     public void setPassword(String password) {
         this.password = password;
     }

     public String getMobile() {
         return mobile;
     }

     public void setMobile(String mobile) {
         this.mobile = mobile;
     }

     public String getTel() {
         return tel;
     }

     public void setTel(String tel) {
         this.tel = tel;
     }

     public String getEmail() {
         return email;
     }

     public void setEmail(String email) {
         this.email = email;
     }

     @Override
     public String toString() {
         return "UserDo{" +
                 "id=" + id +
                 ", userName='" + userName + '\'' +
                 ", password='" + password + '\'' +
                 ", mobile='" + mobile + '\'' +
                 ", tel='" + tel + '\'' +
                 ", email='" + email + '\'' +
                 '}';
     }
 }

7 . 创建好了目录结构之后 , 再配置spring . 在 src/main/resources/spring 目录下面创建 applicationContext.xml . 如下图 :


配置代码如下 :

  <?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:mvc="http://www.springframework.org/schema/mvc"
         xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd">

        <!-- 扫描 controller -->
      <context:component-scan base-package="com.lemy.spring_mybatis.controller" />

      <mvc:annotation-driven>
          <!-- 消息转换器 -->
          <mvc:message-converters register-defaults="true">
              <bean class="org.springframework.http.converter.StringHttpMessageConverter">
                  <property name="supportedMediaTypes">
                      <list>
                          <value>text/html;charset=UTF-8</value>
                          <value>application/json;charset=UTF-8</value>
                      </list>
                  </property>
              </bean>
          </mvc:message-converters>
      </mvc:annotation-driven>

  </beans>

8 . 配置 web.xml 文件

  <!DOCTYPE web-app PUBLIC
          "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
          "http://java.sun.com/dtd/web-app_2_3.dtd" >

  <web-app>
      <display-name>spring-mybatis-demo</display-name>

      <context-param>
          <param-name>contextConfigLocation</param-name>
          <param-value>
              classpath:spring/datasource.xml
          </param-value>
      </context-param>

      <filter>
          <filter-name>HiddenHttpMethodFilter</filter-name>
          <filter-class>org.springframework.web.filter.HiddenHttpMethodFilter</filter-class>
      </filter>

      <filter-mapping>
          <filter-name>HiddenHttpMethodFilter</filter-name>
          <url-pattern>/*</url-pattern>
      </filter-mapping>

      <listener>
          <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
      </listener>

      <servlet>
          <servlet-name>spring-mybatis-servlet</servlet-name>
          <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
          <init-param>
              <param-name>contextConfigLocation</param-name>
              <param-value>classpath:spring/applicationContext.xml</param-value>
          </init-param>
          <load-on-startup>1</load-on-startup>
      </servlet>
      <servlet-mapping>
          <servlet-name>spring-mybatis-servlet</servlet-name>
          <url-pattern>/</url-pattern>
      </servlet-mapping>
  </web-app>

9 . spring MVC 采用RestFul风格的API模式 .

创建UserController , 如下图 :


代码如下 :


  package com.lemy.spring_mybatis.controller;

  import com.google.gson.Gson;
  import com.lemy.spring_mybatis.pojo.UserDo;
  import com.lemy.spring_mybatis.service.UserService;
  import org.springframework.beans.factory.annotation.Autowired;
  import org.springframework.web.bind.annotation.*;

  import java.util.HashMap;
  import java.util.List;

  /**
   * @author leiniao
   */
  @RestController
  public class UserController {

      @Autowired
      private UserService userService;

      private Gson gson = new Gson();

      @RequestMapping(value = "/user/{userId}", method = RequestMethod.GET)
      @ResponseBody
      public String getUser(@PathVariable("userId") Long userId) {
          UserDo userDo = userService.queryUserById(userId);
          return gson.toJson(userDo);
      }


      @RequestMapping(value = "/user/{userId}", method = RequestMethod.PATCH)
      public @ResponseBody List<UserDo> getListByCompanyId(@PathVariable("userId") Long userId, @RequestBody HashMap<String, String> map) {
          System.out.println(userId);
          System.out.println(map);
          Long companyId = Long.valueOf(map.get("companyId"));
          List<UserDo> userList = userService.queryUserListByCompanyId(companyId);
          return userList;
      }



  }

10 . 至此 , Spring + Mybatis的整合就完成了. 可以使用Postman插件去测试你的RestFul的API了 .

Mybatis多数据源的配置(基于AOP配置)

1、创建DynamicDataSource

创建 `DynamicDataSource` 类 , 继承AbstractDataSource类 , 这个是Spring的抽象类 .
改类充当了DataSource的路由中介, 能在运行时, 根据某种key值来动态切换到真正的DataSource上。这个是我们配置多数据源的关键 . 
package com.lemy.spring_mybatis.multiple;

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

/**
 * 动态分配数据库源
 *
 * @author leiniao
 */
public class DynamicDatasource extends AbstractRoutingDataSource {

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

2、创建数据源管理类 DataSourceTypeManager

这个类是用于动态设置数据源的类 . 
package com.lemy.spring_mybatis.multiple;

/**
 * 数据库源类型管理
 *
 * @author leiniao
 */
public class DataSourceTypeManager {

    private static final ThreadLocal<String> dataSourceTypes = new ThreadLocal<String>(){
        @Override
        protected String initialValue() {
            return DataSourceType.MASTER;
        }
    };

    public static String get(){
        return dataSourceTypes.get();
    }

    public static void set(String dataSourceType){
        dataSourceTypes.set(dataSourceType);
    }

    public static void reset(){
        dataSourceTypes.set(DataSourceType.MASTER);
    }

}

3、创建数据源类型的常量类 DataSourceType

这个类就是一个存放数据源类型的常量类
package com.lemy.spring_mybatis.multiple;

/**
 * 数据源类型
 *
 * @author leiniao
 */
public class DataSourceType {

    //主库
    public static final String MASTER = "master";

    //从库
    public static final String SLAVE = "slave";

}

4、多数据源的配置文件

创建 multiple-datasource.xml , 具体配置如下 : 
<?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:tx="http://www.springframework.org/schema/tx" xmlns:aop="http://www.springframework.org/schema/aop"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd   http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd">

    <context:component-scan base-package="com.lemy.spring_mybatis.service"/>
    <context:component-scan base-package="com.lemy.spring_mybatis.multiple"/>

    <!-- 1:引入配置文件 -->
    <bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
        <property name="ignoreUnresolvablePlaceholders" value="true"/>
        <property name="location" value="classpath:jdbc.properties"/>
    </bean>

    <bean id="dataSourceMaster" class="com.alibaba.druid.pool.DruidDataSource"
          destroy-method="close" init-method="init">
        <property name="url" value="${jdbc.url}"/>
        <property name="username" value="${jdbc.username}"/>
        <property name="password" value="${jdbc.password}"/>
    </bean>

    <bean id="dataSourceSlave" class="com.alibaba.druid.pool.DruidDataSource"
          destroy-method="close" init-method="init">
        <property name="url" value="${jdbc.url2}"/>
        <property name="username" value="${jdbc.username2}"/>
        <property name="password" value="${jdbc.password2}"/>
    </bean>

    <bean id="dataSource" class="com.lemy.spring_mybatis.multiple.DynamicDatasource">
        <property name="defaultTargetDataSource" ref="dataSourceMaster"/>
        <property name="targetDataSources">
            <map key-type="java.lang.String">
                <entry key="master" value-ref="dataSourceMaster"/>
                <entry key="slave" value-ref="dataSourceSlave"/>
            </map>
        </property>
    </bean>

    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="dataSource"/>
        <property name="configLocation" value="classpath:mybatis-config.xml"/>
        <property name="mapperLocations" value="classpath:mybatis/*.xml"/>
    </bean>

    <aop:aspectj-autoproxy/>

    <!-- Transaction manager for a single JDBC DataSource -->
    <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
        <property name="dataSource" ref="dataSource"/>
    </bean>

    <!-- 使用annotation定义事务 -->
    <tx:annotation-driven transaction-manager="transactionManager" proxy-target-class="true" order="2"/>
    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
        <property name="basePackage" value="com.lemy.spring_mybatis.mapper"/>
        <!-- 因为sqlSessionFactoryBeanName是动态的 , 因此此处不用配置 -->
        <!-- <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"/> -->
    </bean>
</beans>

5、创建AOP的管理类

创建 DataSourceInterceptor.java 内容如下 :

package com.lemy.spring_mybatis.multiple;

import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.aspectj.lang.annotation.Pointcut;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.context.annotation.EnableAspectJAutoProxy;
import org.springframework.core.annotation.Order;
import org.springframework.stereotype.Component;

/**
 * 基本注解的AOP动态切换数据源
 *
 * @author leiniao
 */
@Aspect
@Component    // 提供spring auto inject bean
@Order(0)    // 请注意:这里order一定要小于tx:annotation-driven的order,即先执行DataSourceInterceptor切面,再执行事务切面,才能获取到最终的数据源
@EnableAspectJAutoProxy(proxyTargetClass = true)
public class DataSourceInterceptor {

    Logger logger = LoggerFactory.getLogger(DataSourceInterceptor.class);

    @Pointcut("execution(* com.lemy.spring_mybatis.mapper.TagsMapper.*(..))")
    public void dataSourceSlave(){
        //do nothing...
        logger.info("use slave datasource");
    }

    @Before("dataSourceSlave()")
    public void beforeSlave(JoinPoint jp) {
        DataSourceTypeManager.set(DataSourceType.SLAVE);
    }

    @Pointcut("execution(* com.lemy.spring_mybatis.mapper.UserMapper.*(..))")
    public void dataSourceMaster(){
        //do nothing...
        logger.info("use master datasource");
    }

    @Before("dataSourceMaster()")
    public void beforeMaster(JoinPoint jp) {
        DataSourceTypeManager.set(DataSourceType.MASTER);
    }


}

至此 , 多数据源的配置就算是完成了 .

PS : Spring AOP的具体用法 , 这里不再说明 . 也不是本文的重点 ,大家可以自己学习AOP的用法 .