27、Mybatis-plus整合多数据源

1、添加所用到的依赖pom.xml

<dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jdbc</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <!-- mybatis-plus的依赖 -->
        <dependency>
            <groupId>com.baomidou</groupId>
            <artifactId>mybatis-plus-boot-starter</artifactId>
            <version>3.1.1</version>
        </dependency>
        <!-- mybatis-plus的自动生成依赖 -->
        <dependency>
            <groupId>com.baomidou</groupId>
            <artifactId>mybatis-plus-generator</artifactId>
            <version>3.0.6</version>
        </dependency>
        <!-- mybatis-plus多数据源 -->
        <dependency>
            <groupId>com.baomidou</groupId>
            <artifactId>dynamic-datasource-spring-boot-starter</artifactId>
            <version>3.3.2</version>
        </dependency>
        
        <dependency>
            <groupId>org.apache.velocity</groupId>
            <artifactId>velocity-engine-core</artifactId>
            <version>2.1</version>
        </dependency>

2、配置application.yml配置文件

spring:
  datasource:
    dynamic:
      primary: master #设置默认的数据源或者数据源组,默认值即为master
      strict: false #严格匹配数据源,默认false. true未匹配到指定数据源时抛异常,false使用默认数据源
      datasource:
        master:
          url: jdbc:mysql://8.129.215.115:3306/mybatis_plus?useUnicode=true&characterEncoding=utf-8&useSSL=false
          username: root
          password: root
          driver-class-name: com.mysql.cj.jdbc.Driver
        slave_1:
          url: jdbc:mysql://8.129.215.115:3306/my_test?useUnicode=true&characterEncoding=utf-8&useSSL=false
          username: root
          password: root
          driver-class-name: com.mysql.cj.jdbc.Driver
        slave_2:
          url: jdbc:mysql://8.129.215.115:3306/cache?useUnicode=true&characterEncoding=utf-8&useSSL=false
          username: root
          password: root
          driver-class-name: com.mysql.cj.jdbc.Driver

3、编写TestService 进行测试

@Service
public class TestService {
    @Autowired
    private JdbcTemplate jdbcTemplate;

    @DS("master")
    public List selectAll() {
        return  jdbcTemplate.queryForList("select * from my_user");
    }

    @DS("slave_1")
    public List test01() {
        return  jdbcTemplate.queryForList("select * from tb_user");
    }

    @DS("slave_2")
    public List selectByCondition() {
        return  jdbcTemplate.queryForList("select * from employee");
    }
}

3、编写测试类进行测试

  @Autowired
    private TestService testService;

    @Test
    void contextLoads() {
        List list = testService.selectAll();
        System.out.println(list);
        List list1 = testService.test01();
        System.out.println(list1);
        List list2 = testService.selectByCondition();
        System.out.println(list2);
    }