1、本文是在《在Docker上搭建MySQL主从复制-主库已有数据》一文的基础上写成的。

2、在pom.xml中引入依赖

<!--shardingsphere start-->
<!-- for spring boot -->
<dependency>
	<groupId>io.shardingsphere</groupId>
	<artifactId>sharding-jdbc-spring-boot-starter</artifactId>
	<version>3.1.0</version>
</dependency>
<!-- for spring namespace -->
<dependency>
	<groupId>io.shardingsphere</groupId>
	<artifactId>sharding-jdbc-spring-namespace</artifactId>
	<version>3.1.0</version>
</dependency>
<!--shardingsphere end-->

3、在application.yml中增加配置信息
在spring下增加allow-bean-definition-overriding，结果如下：

spring:
  #读写分离需要如下配置，否则会报dataSource错误
  main:
    allow-bean-definition-overriding: true

以及sharding的相关配置：

#读写分离
sharding:
  jdbc:
    datasource:
      names: master1,slave0,slave1
      master1:
        type: com.alibaba.druid.pool.DruidDataSource
        driver-class-name: com.mysql.cj.jdbc.Driver
        url: jdbc:mysql://192.168.1.108:5301/test?useUnicode=true&characterEncoding=utf8&zeroDateTimeBehavior=convertToNull&useSSL=true
        username: root
        password: xxx
      slave0:
        type: com.alibaba.druid.pool.DruidDataSource
        driver-class-name: com.mysql.cj.jdbc.Driver
        url: jdbc:mysql://192.168.1.108:5302/test?useUnicode=true&characterEncoding=utf8&zeroDateTimeBehavior=convertToNull&useSSL=true
        username: root
        password: xxx
      slave1:
        type: com.alibaba.druid.pool.DruidDataSource
        driver-class-name: com.mysql.cj.jdbc.Driver
        url: jdbc:mysql://192.168.1.108:5303/test?useUnicode=true&characterEncoding=utf8&zeroDateTimeBehavior=convertToNull&useSSL=true
        username: root
        password: xxx
    # 配置读写分离
    # 配置从库选择策略，提供轮询与随机，这里选择用轮询
    config:
      masterslave:
        load-balance-algorithm-type: round_robin
        name: ms
        master-data-source-name: master1
        slave-data-source-names: slave0,slave1
      # 开启SQL显示，默认值: false，注意：仅配置读写分离时不会打印日志
      props:
        sql:
          show: true

注：我当前的springboot版本为2.2.1，shardingsphere版本为3.1.0，如果启动时有空指针的情况，请检查相关版本信息是否一致。

结果如下：