Springboot之 Mybatis 多数据源实现

简介

解释 Mybatis 实现多数据源 。不同数据库主要用于使用不同的数据库 Mapper 接口分别存储在不同的接口中 package，Spring 扫描不同的包，注入不同的数据源来实现多数据源。原理和 JPA 实现多数据源基本一致。

<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>

第一个主数据源分别是第一个(primary)，第二数据源(second)，具体配置如下：

# server基本配置:  port: 8080# Spring数据库:  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

DataSourceconfit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 */@Configurationpublic 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();    }}

Config数据源Primary

/** * @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);    }}

Student实体类

package com.olive.entity.primary;import java.io.Serializable;import lombok.Data;@Datapublic 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;@Datapublic class TeacherDO implements Serializable {private Long id;private String name;private int sex;private String office;}

Studentmaper

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);}

TeacherMaper

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);}

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>

请注意，这两个xml文件需要放在不同的目录中，如下图所示

package com.olive;import org.springframework.boot.SpringApplication;import org.springframework.boot.autoconfigure.SpringBootApplication;@SpringBootApplicationpublic class Application {    public static void main(String[] args) {        SpringApplication.run(Application.class);    }}

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;@SpringBootTestpublic class MybatisTest {@AutowiredStudentMapper studentMapper;@AutowiredTeacherMapper teacherMapper;@Testpublic 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);}}