读写分离实现效果：写操作使用master主库，读操作使用slave从库
依赖
<dependency> <groupId>com.baomidou</groupId> <artifactId>mybatis-plus-boot-starter</artifactId> <version>3.5.2</version> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <scope>runtime</scope> </dependency> <dependency> <groupId>org.apache.shardingsphere</groupId> <artifactId>sharding-jdbc-spring-boot-starter</artifactId> <version>4.0.0</version> </dependency>
完整依赖 pom.xml
<?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>2.7.7</version> <relativePath/> <!-- lookup parent from repository --> </parent> <groupId>com.example</groupId> <artifactId>demo</artifactId> <version>0.0.1-SNAPSHOT</version> <name>demo</name> <description>Demo project for Spring Boot</description> <properties> <java.version>1.8</java.version> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>com.baomidou</groupId> <artifactId>mybatis-plus-boot-starter</artifactId> <version>3.5.2</version> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <scope>runtime</scope> </dependency> <dependency> <groupId>org.apache.shardingsphere</groupId> <artifactId>sharding-jdbc-spring-boot-starter</artifactId> <version>4.0.0</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>
配置 application.yml
server: port: 8080 mybatis-plus: configuration: map-underscore-to-camel-case: true log-impl: org.apache.ibatis.logging.stdout.StdOutImpl global-config: db-config: id-type: AUTO spring: shardingsphere: sharding: default-data-source-name: master props: sql: # 开启sql显示，默认false show: true datasource: names: master,slave1,slave2 # 主库 master: type: com.zaxxer.hikari.HikariDataSource driver-class-name: com.mysql.cj.jdbc.Driver jdbc-url: jdbc:mysql://127.0.0.1:3306/data?useUnicode=true&characterEncoding=utf-8&serverTimezone=GMT%2B8 username: root password: 123456 # 从库1 slave1: type: com.zaxxer.hikari.HikariDataSource driver-class-name: com.mysql.cj.jdbc.Driver jdbc-url: jdbc:mysql://127.0.0.1:3306/data?useUnicode=true&characterEncoding=utf-8&serverTimezone=GMT%2B8 username: root password: 123456 # 从库2 slave2: type: com.zaxxer.hikari.HikariDataSource driver-class-name: com.mysql.cj.jdbc.Driver jdbc-url: jdbc:mysql://127.0.0.1:3306/data?useUnicode=true&characterEncoding=utf-8&serverTimezone=GMT%2B8 username: root password: 123456 # 读写分离配置 masterslave: # 从库负载均衡策略：轮询 load-balance-algorithm-type: round_robin # 最终的数据源名称 name: dataSource # 主库数据源名称 master-data-source-name: master # 从库数据源名称，多个逗号分隔 slave-data-source-names: slave1,slave2
CREATE TABLE `user` ( `id` int NOT NULL AUTO_INCREMENT, `name` varchar(20), `age` int DEFAULT 0, PRIMARY KEY (`id`) )
实体类
package com.example.demo.entity; import lombok.Data; import java.io.Serializable; @Data public class User implements Serializable { private Long id; private String name; private Integer age; }
Mapper
package com.example.demo.mapper; import com.baomidou.mybatisplus.core.mapper.BaseMapper; import com.example.demo.entity.User; import org.apache.ibatis.annotations.Mapper; @Mapper public interface UserMapper extends BaseMapper<User> { }
IService
package com.example.demo.service; import com.baomidou.mybatisplus.extension.service.IService; import com.example.demo.entity.User; public interface UserService extends IService<User> { }
ServiceImpl
package com.example.demo.service.impl; import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl; import com.example.demo.entity.User; import com.example.demo.mapper.UserMapper; import com.example.demo.service.UserService; import org.springframework.stereotype.Service; @Service public class UserServiceImpl extends ServiceImpl<UserMapper, User> implements UserService { }
Controller
package com.example.demo.controller; import com.example.demo.entity.User; import com.example.demo.service.UserService; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.web.bind.annotation.*; @RestController @RequestMapping("/api/user") public class UserController { @Autowired private UserService userService; @PostMapping("/addUser") public User addUser(@RequestBody User user){ System.out.println(user); userService.save(user); return user; } @GetMapping("/getUserById/{id}") public User getUserById(@PathVariable Long id){ User user = userService.getById(id); user.setId(14L); return user; } }
api测试
POST http://localhost:8080/api/user/addUser Content-Type: application/json { "name": "Tom", "age": 20 } ### GET http://localhost:8080/api/user/getUserById/1 ###
遗留问题：
数据库连接池使用druid，项目启动报错，使用hikari成功启动
参考
