springboot集成mybatis-plus_springboot整合mybatis plus

1. 创建账户表(t_account)

1.1 表结构

备注：采用的是mysql8

1.2 建表sql

CREATE TABLE `t_account` (
  `id` int NOT NULL,
  `user_name` varchar(255) DEFAULT NULL,
  `balance` decimal(10,2) DEFAULT NULL COMMENT '账户余额',
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci;
1
2
3
4
5
6

备注：本文建表采用的是可视化工具navicat界面中创建，并非上述sql，在此贴出，只是为了方便，该SQL正确性待证，见谅！

2. 添加mybatis-plus（简称mp）依赖

<?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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>org.example</groupId>
    <artifactId>spring-boot-test</artifactId>
    <version>1.0-SNAPSHOT</version>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.5.14</version>
    </parent>
    <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>3.5.1</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.29</version>
        </dependency>
    </dependencies>

</project>


1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35

备注：springboot项目搭建见往期文章快速搭建springboot项目

3. 搭建包结构

3.0 为了减少实体类的体积，引入lombok依赖

        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
        </dependency>
1
2
3
4

3.1.实体类

package com.example.entity;


import java.io.Serializable;

import com.baomidou.mybatisplus.annotation.TableField;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
import com.baomidou.mybatisplus.annotation.TableId;
import com.baomidou.mybatisplus.annotation.TableName;
/**
 * @description (Account)表实体类
 * @author wangsm
 */
@Data
@AllArgsConstructor
@NoArgsConstructor
@TableName("t_account")
public class Account  {
        
    @TableId(value = "id", type = IdType.ASSIGN_ID)
    private Long id;
    
        
    @TableField("user_name")
    private String userName;
    
    // 账户余额    
    @TableField("balance")
    private BigDecimal balance;
    
}
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33

3.2 mapper接口

package com.example.mapper;

import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.example.entity.Account;


/**
 * @description (Account)表数据库访问层
 * @author wangsm
 */
public interface AccountMapper extends BaseMapper<Account> {

}
1
2
3
4
5
6
7
8
9
10
11
12
13

3.3 service接口

package com.example.service;

import com.baomidou.mybatisplus.extension.service.IService;
import com.example.entity.Account;


/**
 * @description (Account)表服务接口
 * @author wangsm
 */
public interface AccountService extends IService<Account> {

}
1
2
3
4
5
6
7
8
9
10
11
12
13

3.4 service接口实现类

package com.example.service.impl;

import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.example.entity.Account;
import com.example.mapper.AccountMapper;
import com.example.service.AccountService;
import org.springframework.stereotype.Service;

/**
 * @description (Account)表服务实现类
 * @author wangsm
 */
@Service("accountService")
public class AccountServiceImpl extends ServiceImpl<AccountMapper, Account> implements AccountService {

}
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16

4.添加配置文件

server:
  port: 8888

spring:
  datasource:
    url: jdbc:mysql://ip:3306/transaction?characterEncoding=utf-8&serverTimezone=Asia/Shanghai
    username: 用户名
    password: 密码
    driver-class-name: com.mysql.cj.jdbc.Driver

mybatis-plus:
  configuration:
    # 打印 mp 执行sql的日志
    log-impl: org.apache.ibatis.logging.stdout.StdOutImpl
1
2
3
4
5
6
7
8
9
10
11
12
13
14

5.添加包扫描注解

5.1 在启动类 TestApplication 上添加如下注解

@MapperScan("com.example.mapper")
1

备注：com.example.mapper 表示mapper接口所在的包

6. 测试

6.1 引入测试依赖

说明：为了测试更加方便，引入springboottest依赖，测试环境是否搭建正确。

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
        </dependency>
1
2
3
4

在添加依赖后，刷新maven，可在右侧maven中看到test的依赖。

6.2 添加测试类及测试方法

package com.example.mapper;

import com.example.entity.Account;
import lombok.extern.slf4j.Slf4j;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;

import java.math.BigDecimal;

/**
* @author wangsm
* @description 账户mapper测试类
*/
@Slf4j
@SpringBootTest
public class AccountMapperTest {
  @Autowired
  private AccountMapper accountMapper;
  @Test
  void test(){
      Account entity = new Account();
      entity.setUserName("张三");
      entity.setBalance(new BigDecimal("1000.00"));

      int insertResult = accountMapper.insert(entity);
      log.info("添加结果->{}", insertResult == 1 ? "成功" : "失败");
  }
}
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29

6.3 执行测试方法

6.3.1 控制台结果

6.3.2 数据库

备注：其他查、改、删作可自行测试，在此不做展示！

7. 结束

若有错误，欢迎指正，十分感谢！原创不易，感谢点赞关注