一、配置

比起之前的单数据源配置，只需要在 datasource 下添加多个数据源的配置即可:

  1. mybatis:
  2.   type-aliases-package: com.example.mybatismuti.entity
  3. spring:
  4.   datasource:
  5.     test1:
  6.       driver-class-name: com.mysql.cj.jdbc.Driver
  7.       jdbc-url: jdbc:mysql://localhost:3306/test1?serverTimezone=UTC&useUnicode=true&characterEncoding=utf-8&useSSL=true
  8.       password: root
  9.       username: root
  10.     test2:
  11.       driver-class-name: com.mysql.cj.jdbc.Driver
  12.       jdbc-url: jdbc:mysql://localhost:3306/test2?serverTimezone=UTC&useUnicode=true&characterEncoding=utf-8&useSSL=true
  13.       password: root
  14.       username: root

二、注解版

目录结构

Snipaste_2021-01-06_21-08-59.webp
模型实体类的创建参考：
语雀内容

创建数据源配置

创建两个数据源配置：

@Configuration
@MapperScan(basePackages = "com.example.mybatismuti.mapper.test1", sqlSessionTemplateRef = "test1SqlSessionTemplate")
public class DataSource1Config {

    @Bean(name = "test1DataSource")
    @ConfigurationProperties(prefix = "spring.datasource.test1")
    @Primary
    public DataSource testDataSource() {
        return DataSourceBuilder.create().build();
    }

    @Bean(name = "test1SqlSessionFactory")
    @Primary
    public SqlSessionFactory testSqlSessionFactory(@Qualifier("test1DataSource") DataSource dataSource) throws Exception {
        SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
        bean.setDataSource(dataSource);
        return bean.getObject();
    }

    @Bean(name = "test1TransactionManager")
    @Primary
    public DataSourceTransactionManager testTransactionManager(@Qualifier("test1DataSource") DataSource dataSource) {
        return new DataSourceTransactionManager(dataSource);
    }

    @Bean(name = "test1SqlSessionTemplate")
    @Primary
    public SqlSessionTemplate testSqlSessionTemplate(@Qualifier("test1SqlSessionFactory") SqlSessionFactory sqlSessionFactory) throws Exception {
        return new SqlSessionTemplate(sqlSessionFactory);
    }
}

@Configuration
@MapperScan(basePackages = "com.example.mybatismuti.mapper.test2", sqlSessionTemplateRef = "test2SqlSessionTemplate")
public class DataSource2Config {

    @Bean(name = "test2DataSource")
    @ConfigurationProperties(prefix = "spring.datasource.test2")
    public DataSource testDataSource() {
        return DataSourceBuilder.create().build();
    }

    @Bean(name = "test2SqlSessionFactory")
    public SqlSessionFactory testSqlSessionFactory(@Qualifier("test2DataSource") DataSource dataSource) throws Exception {
        SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
        bean.setDataSource(dataSource);
        return bean.getObject();
    }

    @Bean(name = "test2TransactionManager")
    public DataSourceTransactionManager testTransactionManager(@Qualifier("test2DataSource") DataSource dataSource) {
        return new DataSourceTransactionManager(dataSource);
    }

    @Bean(name = "test2SqlSessionTemplate")
    public SqlSessionTemplate testSqlSessionTemplate(@Qualifier("test2SqlSessionFactory") SqlSessionFactory sqlSessionFactory) throws Exception {
        return new SqlSessionTemplate(sqlSessionFactory);
    }
}

:::info 提示：
@MapperScan 指定要扫描的map包名 :::

数据访问层

DAO 层需要按照库来分在不同的目录，比如：

  • test1 库 DAO层 在 com.example.mybatismuti.mapper.test1 包下
  • test2 库 DAO层 在 com.example.mybatismuti.mapper.test2 包下

创建的方法跟以前的一样，比如：

public interface User1Mapper {
    @Select("SELECT * FROM user")
    @Results({
            @Result(property = "userSex",  column = "user_sex", javaType = UserSexEnum.class),
            @Result(property = "nickName", column = "nick_name")
    })
    List<UserEntity> getAll();

    @Select("SELECT * FROM user WHERE id = #{id}")
    @Results({
            @Result(property = "userSex",  column = "user_sex", javaType = UserSexEnum.class),
            @Result(property = "nickName", column = "nick_name")
    })
    UserEntity getOne(Long id);

    @Insert("INSERT INTO user(user_name,pass_word,user_sex) VALUES(#{userName}, #{passWord}, #{userSex})")
    void insert(UserEntity user);

    @Update("UPDATE user SET user_name=#{userName},nick_name=#{nickName} WHERE id=#{id}")
    void update(UserEntity user);

    @Delete("DELETE FROM user WHERE id=#{id}")
    void delete(Long id);
}

public interface User2Mapper {
    @Select("SELECT * FROM user")
    @Results({
            @Result(property = "userSex",  column = "user_sex", javaType = UserSexEnum.class),
            @Result(property = "nickName", column = "nick_name")
    })
    List<UserEntity> getAll();

    @Select("SELECT * FROM user WHERE id = #{id}")
    @Results({
            @Result(property = "userSex",  column = "user_sex", javaType = UserSexEnum.class),
            @Result(property = "nickName", column = "nick_name")
    })
    UserEntity getOne(Long id);

    @Insert("INSERT INTO user(user_name,pass_word,user_sex) VALUES(#{userName}, #{passWord}, #{userSex})")
    void insert(UserEntity user);

    @Update("UPDATE user SET user_name=#{userName},nick_name=#{nickName} WHERE id=#{id}")
    void update(UserEntity user);

    @Delete("DELETE FROM user WHERE id=#{id}")
    void delete(Long id);
}

在控制器中调用

@RestController
public class UserController {
    @Autowired
    private User1Mapper user1Mapper;

    @Autowired
    private User2Mapper user2Mapper;

    @RequestMapping("/getUsers")
    public List<UserEntity> getUsers() {
        List<UserEntity> users = user1Mapper.getAll();
        return users;
    }

    @RequestMapping("/getUser")
    public UserEntity getUser(Long id) {
        UserEntity user = user2Mapper.getOne(id);
        return user;
    }

    @RequestMapping("/add")
    public void save(UserEntity user) {
        user2Mapper.insert(user);
    }

    @RequestMapping(value = "update")
    public void update(UserEntity user) {
        user2Mapper.update(user);
    }

    @RequestMapping(value = "/delete/{id}")
    public void delete(@PathVariable("id") Long id) {
        user1Mapper.delete(id);
    }
}

三、XML 版

目录结构

Snipaste_2021-01-06_21-21-38.webp

添加MyBatis配置文件

与注解版不同的是，在配置里面添加MyBatis配置文件路径。以便配置别名、下划线转驼峰等信息：

mybatis:
  config-location: classpath:mybatis/mybatis-config.xml
spring:
  datasource:
    test1:
      driver-class-name: com.mysql.cj.jdbc.Driver
      jdbc-url: jdbc:mysql://localhost:3306/test?serverTimezone=UTC&useUnicode=true&characterEncoding=utf-8&useSSL=true
      password: root
      username: root
    test2:
      driver-class-name: com.mysql.cj.jdbc.Driver
      jdbc-url: jdbc:mysql://localhost:3306/test?serverTimezone=UTC&useUnicode=true&characterEncoding=utf-8&useSSL=true
      password: root
      username: root

数据源配置

在数据源配置中修改：

@Bean(name = "test1SqlSessionFactory")
@Primary
public SqlSessionFactory testSqlSessionFactory(@Qualifier("test1DataSource") DataSource dataSource) throws Exception {
    SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
    bean.setDataSource(dataSource);
    bean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources("classpath:mybatis/mapper/test1/*.xml"));
    return bean.getObject();
}

注意这句 bean.setMapperLocations，用于指定 xml 所在位置，这里指定存放于 classpath:mybatis/mapper/test1, 其余的跟之前注解版数据源配置一毛一样。

完整的数据源配置如下：

import org.apache.ibatis.session.SqlSessionFactory;
import org.mybatis.spring.SqlSessionFactoryBean;
import org.mybatis.spring.SqlSessionTemplate;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.boot.jdbc.DataSourceBuilder;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
import org.springframework.jdbc.datasource.DataSourceTransactionManager;

import javax.sql.DataSource;

@Configuration
@MapperScan(basePackages = "com.example.mybatismultixml.mapper.test1", sqlSessionTemplateRef = "test1SqlSessionTemplate")
public class DataSource1Config {

    @Bean(name = "test1DataSource")
    @ConfigurationProperties(prefix = "spring.datasource.test1")
    @Primary
    public DataSource testDataSource() {
        return DataSourceBuilder.create().build();
    }

    @Bean(name = "test1SqlSessionFactory")
    @Primary
    public SqlSessionFactory testSqlSessionFactory(@Qualifier("test1DataSource") DataSource dataSource) throws Exception {
        SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
        bean.setDataSource(dataSource);
        bean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources("classpath:mybatis/mapper/test1/*.xml"));
        return bean.getObject();
    }

    @Bean(name = "test1TransactionManager")
    @Primary
    public DataSourceTransactionManager testTransactionManager(@Qualifier("test1DataSource") DataSource dataSource) {
        return new DataSourceTransactionManager(dataSource);
    }

    @Bean(name = "test1SqlSessionTemplate")
    @Primary
    public SqlSessionTemplate testSqlSessionTemplate(@Qualifier("test1SqlSessionFactory") SqlSessionFactory sqlSessionFactory) throws Exception {
        return new SqlSessionTemplate(sqlSessionFactory);
    }

}

DataSource2Config 的配置也一样，只需要修改一下Mapper文件路径即可：

bean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources("classpath:mybatis/mapper/test2/*.xml"));

在控制器中调用

@RestController
public class UserController {
    @Autowired
    private User1Mapper user1Mapper;

    @Autowired
    private User2Mapper user2Mapper;

    @RequestMapping("/getUsers")
    public List<User> getUsers() {
        List<User> users = user1Mapper.getAll();
        return users;
    }

    @RequestMapping("/getUser")
    public User getUser(Long id) {
        User user = user2Mapper.getOne(id);
        return user;
    }

    @RequestMapping("/add")
    public void save(User user) {
        user2Mapper.insert(user);
    }

    @RequestMapping(value = "update")
    public void update(User user) {
        user2Mapper.update(user);
    }

    @RequestMapping(value = "/delete/{id}")
    public void delete(@PathVariable("id") Long id) {
        user1Mapper.delete(id);
    }
}

参考资料