LinChuJun - Blog

项目结构

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1.分别在mysql主节点和从节点创建db_test，并分别创建表user

CREATE TABLE `user`  (
  `user_id` bigint(20) NOT NULL AUTO_INCREMENT,
  `username` varchar(30) CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL,
  `password` varchar(30) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL,
  PRIMARY KEY (`user_id`) USING BTREE
) ENGINE = InnoDB AUTO_INCREMENT = 6 CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Dynamic;

1. 创建maven工程，并引入依赖

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>2.1.6.RELEASE</version>
</parent>
<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-test</artifactId>
        <scope>test</scope>
    </dependency>
    <!-- sharding -->
    <dependency>
        <groupId>org.apache.shardingsphere</groupId>
        <artifactId>sharding-jdbc-spring-boot-starter</artifactId>
        <version>4.0.0-RC1</version>
    </dependency>
    <!-- mybatis-plus -->
    <dependency>
        <groupId>com.baomidou</groupId>
        <artifactId>mybatis-plus-boot-starter</artifactId>
        <version>3.2.0</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>
    <!-- mysql -->
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>8.0.18</version>
    </dependency>
    <dependency>
        <groupId>com.alibaba</groupId>
        <artifactId>fastjson</artifactId>
        <version>1.2.60</version>
    </dependency>

    <dependency>
        <groupId>org.projectlombok</groupId>
        <artifactId>lombok</artifactId>
        <version>1.18.12</version>
    </dependency>
</dependencies>

2.创建application.yml并修改数据源配置

spring:
  main:
    allow-bean-definition-overriding: true
  shardingsphere:
    datasource:
      names:
        master,slave
      # 主数据源
      master:
        type: com.alibaba.druid.pool.DruidDataSource
        driver-class-name: com.mysql.cj.jdbc.Driver
        url: jdbc:mysql://xxx:3306/db_test?characterEncoding=utf-8
        username: root
        password: xxx
      # 从数据源
      slave:
        type: com.alibaba.druid.pool.DruidDataSource
        driver-class-name: com.mysql.cj.jdbc.Driver
        url: jdbc:mysql://xxx:3307/db_test?characterEncoding=utf-8
        username: root
        password: xxx
    masterslave:
      # 读写分离配置
      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
      # 从库数据源名称列表，多个逗号分隔
      slave-data-source-names: slave
    props:
      # 开启SQL显示，默认false
      sql:
        show: true

3.创建User实体类

@Data
@AllArgsConstructor
@NoArgsConstructor
public class User {

    private Long userId;
    private String username;
    private String password;

    public User(String username, String password) {
        this.username = username;
        this.password = password;
    }
}

4.创建UserMapper

@Mapper
public interface UserMapper {

    @Select("select * from user where user_id = #{userId}")
    User findByUserId(Long userId);

    @Insert("insert into user(username,password) values(#{username},#{password})")
    void addUser(User user);
}

5.创建UserService

@Service
public class UserService {

    @Resource
    private UserMapper userMapper;


    public User findByUserId(Long userId) {
        return userMapper.findByUserId(userId);
    }

    public void addUser(User user) {
        userMapper.addUser(user);
    }
}

6.创建UserController

@RestController
public class UserController {

    @Autowired
    private UserService userService;

    @RequestMapping("/findByUserId")
    @ResponseBody
    public User findByUserId(@RequestParam("userId") Long userId) {
        return userService.findByUserId(userId);
    }

    @GetMapping("/addUser")
    public String addUser(@RequestParam("username")String username,@RequestParam("password") String password) {
        User user = new User(username,password);
        userService.addUser(user);
        return "success";
    }
}

7.创建启动类

@SpringBootApplication
public class ReadWriteSeparationApplication {

    public static void main(String[] args) {
        SpringApplication.run(ReadWriteSeparationApplication.class,args);
    }
}