Springboot之 Mybatis 多数据源实现
简介
上篇讲解了 JPA 多数据源实现；这篇讲解一下 Mybatis 多数据源实现 。主要采用将不同数据库的 Mapper 接口分别存放到不同的 package，Spring 去扫描不同的包，注入不同的数据源来实现多数据源。原理跟 JPA 多数据源实现基本一致。
创建 mybatis-multip-datasource 项目
数据库脚本参考：
pom.xml文件引入如下依赖
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.olive</groupId>
<artifactId>mybatis-multip-datasource</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<name>jpa-multip-datasource</name>
<url>http://maven.apache.org</url>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.5.14</version>
<relativePath /> <!-- lookup parent from repository -->
</parent>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<maven.compiler.source>8</maven.compiler.source>
<maven.compiler.target>8</maven.compiler.target>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>2.1.3</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
</dependencies>
</project>
配置两个数据源
分别为第一个主数据源(primary)，第二数据源(second)，具体配置如下：
# 基本配置
server:
port: 8080
# 数据库
spring:
datasource:
primary:
driver-class-name: com.mysql.jdbc.Driver
jdbc-url: jdbc:mysql://127.0.0.1:3306/db01?characterEncoding=utf-8&allowMultiQueries=true&autoReconnect=true
username: root
password: root
second:
driver-class-name: com.mysql.cj.jdbc.Driver
jdbc-url: jdbc:mysql://127.0.0.1:3306/crm72?characterEncoding=utf-8&allowMultiQueries=true&autoReconnect=true
username: root
password: root
jackson:
serialization:
indent-output: true
配置数据源
DataSourceConfig配置
package com.olive.config;
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 javax.sql.DataSource;
/**
* @Description: 数据源配置
*/
@Configuration
public class DataSourceConfig {
@Bean(name = "primaryDataSource")
@Qualifier("primaryDataSource")
@ConfigurationProperties(prefix = "spring.datasource.primary")
@Primary
public DataSource primaryDataSource() {
return DataSourceBuilder.create().build();
}
@Bean(name = "secondDataSource")
@Qualifier("secondDataSource")
@ConfigurationProperties(prefix = "spring.datasource.second")
public DataSource secondDataSource() {
return DataSourceBuilder.create().build();
}
}
PrimaryConfig数据源
/**
* @Description: 主数据源配置
*/
@Configuration
@MapperScan(basePackages = "com.olive.mapper.primary",
sqlSessionTemplateRef = "primarySqlSessionTemplate")
public class PrimaryConfig {
@Autowired
@Qualifier("primaryDataSource")
private DataSource primaryDataSource;
@Bean(name = "primarySqlSessionFactory")
@Primary
public SqlSessionFactory primarySqlSessionFacotory() throws Exception {
SqlSessionFactoryBean sqlSessionFactoryBean = new SqlSessionFactoryBean();
sqlSessionFactoryBean.setDataSource(primaryDataSource);
sqlSessionFactoryBean.setMapperLocations(new PathMatchingResourcePatternResolver()
.getResources("classpath:mapper/primary/*.xml"));
return sqlSessionFactoryBean.getObject();
}
@Bean(name = "primaryTransactionManager")
@Primary
public DataSourceTransactionManager primaryTransactionManager() {
return new DataSourceTransactionManager(primaryDataSource);
}
@Bean(name = "primarySqlSessionTemplate")
@Primary
public SqlSessionTemplate primarySqlSessionTemplate(@Qualifier("primarySqlSessionFactory") SqlSessionFactory sqlSessionFactory) {
return new SqlSessionTemplate(sqlSessionFactory);
}
}
SecondConfig数据源
/**
* @Description: 主数据源配置
*/
@Configuration
@MapperScan(basePackages = "com.olive.mapper.second",
sqlSessionTemplateRef = "secondSqlSessionTemplate")
public class SecondConfig {
@Autowired
@Qualifier("secondDataSource")
private DataSource secondDataSource;
@Bean(name = "secondSqlSessionFactory")
public SqlSessionFactory secondSqlSessionFacotory() throws Exception {
SqlSessionFactoryBean sqlSessionFactoryBean = new SqlSessionFactoryBean();
sqlSessionFactoryBean.setDataSource(secondDataSource);
sqlSessionFactoryBean.setMapperLocations(new PathMatchingResourcePatternResolver()
.getResources("classpath:mapper/second/*.xml"));
return sqlSessionFactoryBean.getObject();
}
@Bean(name = "secondTransactionManager")
public DataSourceTransactionManager secondTransactionManager() {
return new DataSourceTransactionManager(secondDataSource);
}
@Bean(name = "secondSqlSessionTemplate")
public SqlSessionTemplate secondSqlSessionTemplate(@Qualifier("secondSqlSessionFactory") SqlSessionFactory sqlSessionFactory) {
return new SqlSessionTemplate(sqlSessionFactory);
}
}
创建学生与老师实体类
Student实体类
package com.olive.entity.primary;
import java.io.Serializable;
import lombok.Data;
@Data
public class StudentDO implements Serializable{
private Long id;
private String name;
private int sex;
private String grade;
}
Teacher实体类
package com.olive.entity.second;
import java.io.Serializable;
import lombok.Data;
@Data
public class TeacherDO implements Serializable {
private Long id;
private String name;
private int sex;
private String office;
}
数据库持久类
StudentMapper类
package com.olive.mapper.primary;
import com.olive.entity.primary.StudentDO;
import org.apache.ibatis.annotations.Param;
public interface StudentMapper {
int save(@Param("studentDO") StudentDO studentDO);
}
TeacherMapper类
package com.olive.mapper.second;
import com.olive.entity.second.TeacherDO;
import org.apache.ibatis.annotations.Param;
public interface TeacherMapper {
int save(@Param("teacherDO") TeacherDO teacherDO);
}
Mybatis xml映射
StudentMapper.xml
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.olive.mapper.primary.StudentMapper">
<resultMap id="BaseResultMap" type="com.olive.entity.primary.StudentDO">
<id column="id" jdbcType="BIGINT" property="id" />
<result column="name" jdbcType="VARCHAR" property="name" />
<result column="sex" jdbcType="INTEGER" property="sex" />
<result column="grade" jdbcType="VARCHAR" property="grade" />
</resultMap>
<insert id="save">
INSERT INTO t_student (user_name, sex, grade) VALUES (#{studentDO.name}, #{studentDO.sex}, #{studentDO.grade});
</insert>
</mapper>
TeacherMapper.xml
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.olive.mapper.second.TeacherMapper">
<resultMap id="BaseResultMap" type="com.olive.entity.second.TeacherDO">
<id column="id" jdbcType="BIGINT" property="id" />
<result column="name" jdbcType="VARCHAR" property="name" />
<result column="sex" jdbcType="INTEGER" property="sex" />
<result column="office" jdbcType="VARCHAR" property="office" />
</resultMap>
<insert id="save">
INSERT INTO t_teacher ( user_name, sex, office) VALUES (#{teacherDO.name}, #{teacherDO.sex}, #{teacherDO.office});
</insert>
</mapper>
主要注意这两个xml文件需要放到不同的目录，如下图
创建springboot引导类
package com.olive;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication
public class Application {
public static void main(String[] args) {
SpringApplication.run(Application.class);
}
}
测试
package com.olive;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import com.olive.entity.primary.StudentDO;
import com.olive.entity.second.TeacherDO;
import com.olive.mapper.primary.StudentMapper;
import com.olive.mapper.second.TeacherMapper;
@SpringBootTest
public class MybatisTest {
@Autowired
StudentMapper studentMapper;
@Autowired
TeacherMapper teacherMapper;
@Test
public void userSave() {
StudentDO studentDO = new StudentDO();
studentDO.setName("BUG弄潮儿");
studentDO.setSex(1);
studentDO.setGrade("一年级");
studentMapper.save(studentDO);
TeacherDO teacherDO = new TeacherDO();
teacherDO.setName("Java乐园");
teacherDO.setSex(2);
teacherDO.setOffice("语文");
teacherMapper.save(teacherDO);
}
}
