Sharding JDBC 读写分离

环境需要

JDK 1.8
实现主从复制的两个数据库（主库、从库至少各一）

依赖

<dependencies>
        <!--springboot依赖-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
            <exclusions>
                <exclusion>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>org.springframework.boot:spring-boot-starter-logging</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <!-- springboot 测试框架 -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
        </dependency>

        <!--lombok-->
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>

        <!--mybatis-plus对springboot支持，不用再单独导入mp的依赖-->
        <dependency>
            <groupId>com.baomidou</groupId>
            <artifactId>mybatis-plus-boot-starter</artifactId>
            <version>3.1.1</version>
        </dependency>

        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.12</version>
        </dependency>

        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-log4j12</artifactId>
        </dependency>

        <!-- sharding -->
        <dependency>
            <groupId>org.apache.shardingsphere</groupId>
            <artifactId>sharding-jdbc-spring-boot-starter</artifactId>
            <version>4.0.0-RC1</version>
        </dependency>

        <!--阿里数据库连接池 -->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid-spring-boot-starter</artifactId>
            <version>1.1.14</version>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
    </dependencies>

配置文件

spring:
  main:
    allow-bean-definition-overriding: true
  shardingsphere:
    datasource:
      names: master,slave
      master:
        type: com.alibaba.druid.pool.DruidDataSource
        driver-class-name: com.mysql.cj.jdbc.Driver
        url: jdbc:mysql://39.97.225.133:33306/master_test?useUnicode=true&characterEncoding=UTF-8
        username: root
        password: root
      slave:
        type: com.alibaba.druid.pool.DruidDataSource
        driver-class-name: com.mysql.cj.jdbc.Driver
        url: jdbc:mysql://39.97.225.133:33307/master_test?useUnicode=true&characterEncoding=UTF-8
        username: root
        password: root
    masterslave:
      # \u8BFB\u5199\u5206\u79BB\u914D\u7F6E
      load-balance-algorithm-type: round_robin 轮询
      # \u6700\u7EC8\u7684\u6570\u636E\u6E90\u540D\u79F0
      name: dataSource
      # \u4E3B\u5E93\u6570\u636E\u6E90\u540D\u79F0 主库
      master-data-source-name: master
      # \u4ECE\u5E93\u6570\u636E\u6E90\u540D\u79F0\u5217\u8868\uFF0C\u591A\u4E2A\u9017\u53F7\u5206\u9694 从库
      slave-data-source-names: slave
    props:
      # \u5F00\u542FSQL\u663E\u793A\uFF0C\u9ED8\u8BA4false
      sql:
        show: true

测试，观察控制台日志输出，可以发现读操作和写操作时使用的是不同的数据库，即读写分离成功实现

@RunWith(SpringJUnit4ClassRunner.class)
@SpringBootTest
public class DemoApplicationTests {

    @Autowired
    private UserMapper userMapper;

    @Test
    public void testSearch() {
        List<User> users= userMapper.selectList(null);
        System.out.println(users);
    }

    @Test
    public void testSave() {
        User user= new User();
        user.setId(1L);
        userMapper.insert(user);
    }

}