SpringBoot-Mybatis多数据源配置

作者 | springboot葵花宝典
来源 | 今日头条

之前我们介绍过Mybatis代码生成有两种方式：

• Mybatis Genenrator Mybatis代码生成
• Mybtais Plus MyBatisPlus代码生成

在之前介绍JdbcTemplate和Spring-Boot-Data操作数据库的时候也分别介绍了

• JdbcTemplate多数据源配置
• Spring-Data-JPA多数据源配置本次章节的实体类的sql也在该章节

今天我们介绍Mybatis使用时候的多数源配置如何实现。

该测试项目的整体框架如下：

多数据源配置

在项目的application.yml中设置要链接的数据库，配置如下：

server:
  port: 8899
spring:
  datasource:
    student:
      jdbc-url: jdbc:mysql://localhost:3306/mybatis?useUnicode=true&serverTimezone=Asia/Shanghai&characterEncoding=utf-8&useSSL=false
      username: root
      password: root
      driver-class-name: com.mysql.cj.jdbc.Driver # 3.2.0开始支持SPI可省略此配置
    teacher:
      jdbc-url: jdbc:mysql://localhost:3306/mysql?useUnicode=true&serverTimezone=Asia/Shanghai&characterEncoding=utf-8&useSSL=false
      username: root
      password: root
      driver-class-name: com.mysql.cj.jdbc.Driver

注：

在spring1.x和spring2.x中数据库配置链接关键字有区别：

• 在1.x中配置的是spring.datasource.XXX.url
• 在2.x中配置的是spring.datasource.XXX.jdbc-url

数据源的配置

主数据源的配置

在这次配置中我们将mybatis数据库作为主数据库，里面包含了student表，其主要配置如下：

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.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 javax.sql.DataSource;
@Configuration
//数据源student库接口存放目录
@MapperScan(basePackages = "com.learn.springboot.entity.student",
        sqlSessionTemplateRef = "sqlSessionTemplateStudent")
public class MybatisStudentConfig {
    /**
     * 主数据源默认使用Student
     *
     * @return
     */
    @Primary
    @Bean
    @ConfigurationProperties(prefix = "spring.datasource.student")
    public DataSource studentDataSource() {
        return DataSourceBuilder.create().build();
    }
    @Bean
    public SqlSessionFactory sqlSessionFactoryStudent() throws Exception {
        SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
        bean.setDataSource(studentDataSource());
        //设置XML文件存放位置.注意这里student目录
        bean.setMapperLocations(new PathMatchingResourcePatternResolver()
                .getResources("classpath:mapper/student/*.xml")); 
        return bean.getObject();
    }
    @Bean
    public SqlSessionTemplate sqlSessionTemplateStudent() throws Exception {
        return new SqlSessionTemplate(sqlSessionFactoryStudent());
    }
}

注：

• 主数据源要是有**@Primary**进行表示
• bean.setMapperLocations(new PathMatchingResourcePatternResolver()
• .getResources("classpath:mapper/teacher/*.xml"));用于配置xml的位置
• 配置类上使用@MapperScan注解来是用来扫描实体类和Mapper包路径

非主数据源的配置

在这次配置中我们将mysql数据库作为非主数据库，里面包含了teacher表，其主要配置如下：

@Configuration
//数据源teacher库接口存放目录
@MapperScan(basePackages = "com.learn.springboot.entity.teacher",
        sqlSessionTemplateRef = "sqlSessionTemplateTeacher")
public class MybatisTeacherConfig {
    /**
     * 主数据源默认使用Student
     *
     * @return
     */
    @Bean
    @ConfigurationProperties(prefix = "spring.datasource.teacher")
    public DataSource teacherDataSource() {
        return DataSourceBuilder.create().build();
    }
    @Bean
    public SqlSessionFactory sqlSessionFactoryTeacher() throws Exception {
        SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
        bean.setDataSource(teacherDataSource());
        //设置XML文件存放位置,注意这里teacher目录
        bean.setMapperLocations(new PathMatchingResourcePatternResolver()
                .getResources("classpath:mapper/teacher/*.xml"));
        return bean.getObject();
    }
    @Bean
    public SqlSessionTemplate sqlSessionTemplateTeacher() throws Exception {
        return new SqlSessionTemplate(sqlSessionFactoryTeacher());
    }
}

实体类的创建

本次章节的实体类分别有student和teacher两个实体类，代码如下

@Data
public class Student {
    private Long id;
    private String name;
    private String sex;
    private int age;
    private String email;
    private String mobile;
    private int isEnabled;
    private Date createDate;
    private Date updateDate;
}
@Data
public class Teacher {
    private Long id;
    private String name;
    private String sex;
    private String course;
    private int age;
    private String email;
    private String mobile;
    private int isEnabled;
    private Date createDate;
    private Date updateDate;
}

Mapper的实现

student的mapper接口的xml配置实现如下

• studentmapper接口

public interface StudentMapper {
    Student findById(@Param("id") Long id);
    void updateStudent(Student student);
    int insertByObject(Student student);
}

• studentmapper的xml配置如下

<?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.learn.springboot.entity.student.StudentMapper">
    <select id="findById" resultType="com.learn.springboot.entity.student.Student">
        SELECT * FROM STUDENT WHERE ID = #{id}
    </select>
    <insert id="insertByObject">
        INSERT INTO STUDENT(NAME, SEX,AGE,EMAIL,MOBILE) VALUES(#{name}, #{sex}, #{age}, #{email}, #{mobile})
    </insert>
    <update id="updateStudent" parameterType="com.learn.springboot.entity.student.Student">
       UPDATE STUDENT SET NAME=#{name},SEX=#{sex},AGE=#{age},EMAIL=#{email},MOBILE=#{mobile} WHERE id=#{id}
    </update>
</mapper>

teacher的mapper接口的xml配置实现如下

• teachermapper的接口如下：

public interface TeacherService {
    Teacher updateTeacher(Teacher teacher);
    int insertByObject(Teacher teacher);
    Teacher findById(Long id);
}

• teachermapper的xml配置如下

<?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.learn.springboot.entity.teacher.TeacherMapper">
    <select id="findById" resultType="com.learn.springboot.entity.teacher.Teacher">
        SELECT * FROM TEACHER WHERE ID = #{id}
    </select>
    <insert id="insertByObject">
        INSERT INTO TEACHER(NAME, SEX,AGE,EMAIL,MOBILE) VALUES(#{name}, #{sex}, #{age}, #{email}, #{mobile})
    </insert>
    <update id="updateTeacher" parameterType="com.learn.springboot.entity.teacher.Teacher">
       UPDATE TEACHER SET NAME=#{name},SEX=#{sex},AGE=#{age},EMAIL=#{email},MOBILE=#{mobile} WHERE id=#{id}
    </update>
</mapper>

Service层的实现

student的Service层实现

student的service包含studentservice接口和其实现StudentServiceimpl代码实现如下：

• StudentService接口的实现

public interface StudentService {
    Student updateStudent(Student student);
    int insertByObject(Student student);
    Student findById(Long id);
}

• StudentServiceImpl的实现代码：

@Service
public class StudentServiceImpl implements StudentService {
    private StudentMapper studentMapper;
    @Override
    public int insertByObject(Student student){
        return  studentMapper.insertByObject(student);
    }
    @Override
    public Student updateStudent(Student student){
        studentMapper.updateStudent(student);
        return  student;
    }
    @Override
    public Student findById(Long id) {
        return studentMapper.findById(id);
    }
}

teacher的Service实现

student的service包含studentservice接口和其实现StudentServiceimpl代码实现如下：

• StudentService接口的实现

public interface TeacherService {
    Teacher updateTeacher(Teacher teacher);
    int insertByObject(Teacher teacher);
    Teacher findById(Long id);
}

• TeacherServiceImpl的实现代码：

@AllArgsConstructor
@Service
public class TeacherServiceImpl implements TeacherService {
    private TeacherMapper teacherMapper;
    @Override
    public int insertByObject(Teacher teacher){
        return  teacherMapper.insertByObject(teacher);
    }
    @Override
    public Teacher updateTeacher(Teacher teacher){
        teacherMapper.updateTeacher(teacher);
        return  teacher;
    }
    @Override
    public Teacher findById(Long id) {
        return teacherMapper.findById(id);
    }
}

控制层的实现

• Student的控制层代码实现如下

@Slf4j
@RequestMapping("/student")
@RestController
@AllArgsConstructor
public class StudentController {
    /**
     * studentService注入StudentController
     */
    private StudentService studentService;
    @PostMapping("insert")
    public int insertByObject(@RequestBody Student student){
        return  studentService.insertByObject(student);
    }
    @PostMapping("update")
    public Student updateStudent(@RequestBody Student student) {
        return   studentService.updateStudent(student);
    }
    @GetMapping("/select/{id}")
    public Student findByName(@PathVariable("id") Long id) {
        return studentService.findById(id);
    }
}

• Teacher的控制层代码实现如下

@Slf4j
@RequestMapping("/teacher")
@RestController
@AllArgsConstructor
public class TeacherController {
    /**
     * teacherService注入TeacherController
     */
    private TeacherService teacherService;
    @PostMapping("insert")
    public int insertByObject(@RequestBody Teacher teacher){
        return  teacherService.insertByObject(teacher);
    }
    @PostMapping("update")
    public Teacher updateStudent(@RequestBody Teacher teacher) {
        return   teacherService.updateTeacher(teacher);
    }
    @GetMapping("/select/{id}")
    public Teacher findByName(@PathVariable("id") Long id) {
        return teacherService.findById(id);
    }
}

测试

使用postman分别测试

• http://localhost:8899/student/select/11 Get方法
• http://localhost:8899/teacher/update Post方法
• http://localhost:8899/teacher/select/11 Get方法

分别测试了student和teacher的方法以及Get和Post方法。