这篇文章将为大家详细讲解有关SpringBoot中怎么利用Sharding-JDBC实现MySQL8读写分离，文章内容质量较高，因此小编分享给大家做个参考，希望大家阅读完这篇文章后对相关知识有一定的了解。
一.前言
这是一个基于SpringBoot整合Sharding-JDBC实现读写分离的极简教程，笔者使用到的技术及版本如下：
SpringBoot 2.5.2
MyBatis-Plus 3.4.3
Sharding-JDBC 4.1.1
MySQL8集群（看笔者前一篇文章有部署教程）
二.项目目录结构
三.pom文件
<?xml version="1.0" encoding="UTF-8"?><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 https://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.5.2</version> <relativePath/> <!-- lookup parent from repository --> </parent> <groupId>xyz.hcworld</groupId> <artifactId>sharding-jdbc-demo</artifactId> <version>0.0.1-SNAPSHOT</version> <name>sharding-jdbc-demo</name> <description>多数据源切换实例</description> <properties> <java.version>1.8</java.version> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <!-- mybatis-plus依赖 --> <dependency> <groupId>com.baomidou</groupId> <artifactId>mybatis-plus-boot-starter</artifactId> <version>3.4.3</version> </dependency> <!-- mysql驱动 --> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <scope>runtime</scope> </dependency> <!-- sharding-jdbc（多数据源切换） --> <dependency> <groupId>org.apache.shardingsphere</groupId> <artifactId>sharding-jdbc-spring-boot-starter</artifactId> <version>4.1.1</version> </dependency> <dependency> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> <optional>true</optional> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> <configuration> <excludes> <exclude> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> </exclude> </excludes> </configuration> </plugin> </plugins> </build></project>四.配置文件（基于YAML）及SQL建表语句
spring: main: allow-bean-definition-overriding: true #显示sql shardingsphere: props: sql: show: true masterslave: #配置主从名称 name: ms #置主库master,负责数据的写入 master-data-source-name: ds1 #配置从库slave节点 slave-data-source-names: ds2,ds3 #配置slave节点的负载均衡均衡策略,采用轮询机制，有两种算法：round_robin(轮询)和random(随机) load-balance-algorithm-type: round_robin sharding: #配置默认数据源ds1 默认数据源,主要用于写 default-data-source-name: ds1 # 配置数据源 datasource: names: ds1,ds2,ds3 #master-ds1数据库连接信息 ds1: type: com.zaxxer.hikari.HikariDataSource driver-class-name: com.mysql.cj.jdbc.Driver jdbc-url: jdbc:mysql://192.168.2.142:3307/sharding-jdbc-db?useUnicode=true&useSSL=false&serverTimezone=Asia/Shanghai username: root password: 123456 maxPoolSize: 100 minPoolSize: 5 #slave-ds2数据库连接信息 ds2: type: com.zaxxer.hikari.HikariDataSource driver-class-name: com.mysql.cj.jdbc.Driver jdbc-url: jdbc:mysql://192.168.2.142:3308/sharding-jdbc-db?useUnicode=true&useSSL=false&serverTimezone=Asia/Shanghai username: root password: 123456 maxPoolSize: 100 minPoolSize: 5 #slave-ds3数据库连接信息 ds3: type: com.zaxxer.hikari.HikariDataSource driver-class-name: com.mysql.cj.jdbc.Driver jdbc-url: jdbc:mysql://192.168.2.142:3309/sharding-jdbc-db?useUnicode=true&useSSL=false&serverTimezone=Asia/Shanghai username: root password: 123456 maxPoolSize: 100 minPoolSize: 5#mybatis-plus配置mybatis-plus: type-aliases-package: xyz.hcworld.demo.model mapper-locations: classpath*:/mapper@Componentpublic interface UserMapper extends BaseMapper<User> { void addUser(User user); List<User> findUsers();}六 .Controller及Mocel文件
package xyz.hcworld.demo.controller;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.web.bind.annotation.GetMapping;import org.springframework.web.bind.annotation.PostMapping;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.bind.annotation.RestController;import xyz.hcworld.demo.mapper.UserMapper;import xyz.hcworld.demo.model.User;import java.security.SecureRandom;import java.util.List;@RestController@RequestMapping("/api/user")public class UserController { @Autowired private UserMapper userMapper; @PostMapping("/save") public String addUser() { User user = new User(); user.setNickname("zhangsan" + new SecureRandom().nextInt()); user.setPassword("123456"); user.setSex(1); user.setBirthday("1997-12-03"); userMapper.addUser(user); return user.toString(); } @GetMapping("/findUsers") public List<User> findUsers() { return userMapper.findUsers(); }}package xyz.hcworld.demo.model;import com.baomidou.mybatisplus.annotation.IdType;import com.baomidou.mybatisplus.annotation.TableId;import com.baomidou.mybatisplus.annotation.TableName;import lombok.Data;import lombok.EqualsAndHashCode;@Data@TableName("t_user")public class User { private static final long serialVersionUID = 1L; @TableId(value = "id", type = IdType.AUTO) private Integer id; private String nickname; private String password; private Integer sex; private String birthday;}七.结果
从结果可以看出，写入操作全部通过ds1数据库（master）数据库完成，而读操作因为设置了轮询的缘故，由ds2（slaver）、ds3（slaver2）数据库完成。这样就实现了基于一主二从的数据库集群的读写分离操作。
八.Sharding-JDBC不同版本上的配置
网上Sharding-JDBC的教程多为4.0.0.RC1版本，笔者使用的是最新的4.1.1所以
在该部分数据库地址在4.1.1为jdbc-url在4.0.0.RC1上需要改为url否则会启动失败
jdbc-url: jdbc:mysql://XXXX/XXXX关于SpringBoot中怎么利用Sharding-JDBC实现MySQL8读写分离就分享到这里了，希望以上内容可以对大家有一定的帮助，可以学到更多知识。如果觉得文章不错，可以把它分享出去让更多的人看到。
