1
<!-- SpringBoot3 适配核心依赖 -->
2
<!-- MyBatisPlus 适配SpringBoot3 专属依赖 -->
3
<dependency>
4
<groupId>com.baomidou</groupId>
5
<artifactId>mybatis-plus-spring-boot3-starter</artifactId>
6
<version>3.5.6</version>
7
</dependency>
8

9
<!-- MySQL8+ 驱动（SpringBoot3 必须使用新驱动） -->

1
<dependency>
2
<groupId>com.mysql</groupId>
3
<artifactId>mysql-connector-j</artifactId>
4
<scope>runtime</scope>
5
</dependency>
6

7
<!-- lombok 简化实体类 -->
8
<dependency>
9
<groupId>org.projectlombok</groupId>
10
<artifactId>lombok</artifactId>
11
<optional>true</optional>
12
</dependency>
13

14
<!-- SpringBoot3 测试依赖 -->
15
<dependency>
16
<groupId>org.springframework.boot</groupId>
17
<artifactId>spring-boot-starter-test</artifactId>
18
<scope>test</scope>
19
</dependency>

1
spring:
2
# 数据源配置
3
datasource:
4
url: jdbc:mysql://localhost:3306/java2601?useUnicode=true&characterEncoding=utf-
5
8&serverTimezone=UTC&allowMultiQueries=true
6
username: root
7
password: root
8
driver-class-name: com.mysql.cj.jdbc.Driver
9

10
# MyBatisPlus 全局配置
11
mybatis-plus:
12
# 映射文件路径
13
mapper-locations: classpath:mapper/*.xml
14
# 实体类别名包
15
type-aliases-package: com.mp.demo.entity
16
configuration:
17
# 开启下划线转驼峰自动映射
18
map-underscore-to-camel-case: true
19
# 开启SQL日志打印
20
log-impl: org.apache.ibatis.logging.stdout.StdOutImpl
21
global-config:
22
db-config:
23
# 主键自增策略
24
id-type: auto
25
# 数据库表前缀（可选）
26
# table-prefix: tb_
27
# 逻辑删除全局配置
28
logic-delete-field: deleteFlag

1
import org.mybatis.spring.annotation.MapperScan;
2
import org.springframework.boot.SpringApplication;
3
import org.springframework.boot.autoconfigure.SpringBootApplication;
4

5
// SpringBoot3 启动类无任何兼容问题，注解完全通用
6
@SpringBootApplication
7
@MapperScan("com.mp.demo.mapper")
8
public class MpDemoApplication {
9
public static void main(String[] args) {
10
SpringApplication.run(MpDemoApplication.class, args);
11
}
12
}

1
import java.util.UUID;
2

3
public class UUIDTest {
4
public static void main(String[] args) {
5
// 生成标准UUID v4（MP ASSIGN_UUID底层实现）
6
UUID uuid = UUID.randomUUID();
7
System.out.println("标准UUID：" + uuid);
8

9
// 企业常用：去除横线，精简存储长度
10
String simpleUuid = uuid.toString().replace("-", "");
11
System.out.println("无横线UUID：" + simpleUuid);
12
}
13
}

1
import com.baomidou.mybatisplus.annotation.IdType;
2
import com.baomidou.mybatisplus.annotation.TableId;
3
import lombok.Data;
4

5
@Data
6
public class User {
7
// 自动生成UUID字符串主键
8
@TableId(type = IdType.ASSIGN_UUID)
9
private String id;
10

11
// 其他字段省略
12
}

1
import com.baomidou.mybatisplus.core.mapper.BaseMapper;
2
import com.mp.demo.entity.User;
3
import org.apache.ibatis.annotations.Mapper;
4

5
@Mapper
6
public interface UserMapper extends BaseMapper<User> {
7
// 无需编写任何代码，继承BaseMapper即可拥有所有CRUD方法
8
}

1
import com.mp.demo.entity.User;
2
import com.mp.demo.mapper.UserMapper;
3
import org.junit.jupiter.api.Test;
4
import org.springframework.beans.factory.annotation.Autowired;
5
import org.springframework.boot.test.context.SpringBootTest;
6
import java.util.List;
7

8
@SpringBootTest
9
public class MapperCrudTest {
10

11
@Autowired
12
private UserMapper userMapper;
13

14
// 新增
15
@Test
16
void testInsert() {
17
User user = new User();
18
user.setName("张三");
19
user.setAge(20);
20
user.setEmail("zhangsan@163.com");
21
// 返回受影响行数
22
int insert = userMapper.insert(user);
23
System.out.println("新增ID：" + user.getId());
24
}
25

26
// 根据ID查询
27
@Test

1
void testSelectById() {
2
User user = userMapper.selectById(1L);
3
System.out.println(user);
4
}
5

6
// 查询所有
7
@Test
8
void testSelectList() {
9
List<User> userList = userMapper.selectList(null);
10
userList.forEach(System.out::println);
11
}
12

13
// 根据ID更新
14
@Test
15
void testUpdateById() {
16
User user = new User();
17
user.setId(1L);
18
user.setAge(22);
19
user.setEmail("update@163.com");
20
int rows = userMapper.updateById(user);
21
System.out.println("更新行数：" + rows);
22
}
23

24
// 根据ID删除
25
@Test
26
void testDeleteById() {
27
int rows = userMapper.deleteById(1L);
28
System.out.println("删除行数：" + rows);
29
}
30
}

1
// 接口
2
import com.baomidou.mybatisplus.extension.service.IService;
3
import com.mp.demo.entity.User;
4
public interface UserService extends IService<User> {
5
}
6

7
// 实现类
8
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
9
import com.mp.demo.entity.User;
10
import com.mp.demo.mapper.UserMapper;
11
import com.mp.demo.service.UserService;
12
import org.springframework.stereotype.Service;
13

14
@Service
15
public class UserServiceImpl extends ServiceImpl<UserMapper, User> implements UserService {

1
}

1
@SpringBootTest
2
public class ServiceCrudTest {
3

4
@Autowired
5
private UserService userService;
6

7
// 批量新增
8
@Test
9
void testBatchSave() {
10
List<User> list = new ArrayList<>();
11
list.add(new User(null, "李四", 25, "lisi@163.com", null, null, null));
12
list.add(new User(null, "王五", 28, "wangwu@163.com", null, null, null));
13
// 批量插入
14
boolean batch = userService.saveBatch(list);
15
System.out.println("批量新增结果：" + batch);
16
}
17

18
// 新增或更新（ID存在则更新，不存在则新增）
19
@Test
20
void testSaveOrUpdate() {
21
User user = new User(2L, "李四", 26, "lisi_new@163.com", null, null, null);
22
boolean result = userService.saveOrUpdate(user);
23
}
24

25
// 批量删除
26
@Test
27
void testBatchDelete() {
28
userService.removeByIds(Arrays.asList(3L,4L));
29
}
30
}

1
import com.baomidou.mybatisplus.core.handlers.MetaObjectHandler;
2
import org.apache.ibatis.refiection.MetaObject;
3
import org.springframework.stereotype.Component;
4
import java.time.LocalDateTime;
5

6
@Component
7
public class MyMetaObjectHandler implements MetaObjectHandler {
8

9
// 插入时自动填充
10
@Override
11
public void insertFill(MetaObject metaObject) {
12
this.strictInsertFill(metaObject, "createTime", LocalDateTime::now, LocalDateTime.class);
13
this.strictInsertFill(metaObject, "updateTime", LocalDateTime::now, LocalDateTime.class);
14
this.strictInsertFill(metaObject, "deleteFlag", () -> 0, Integer.class);
15
}
16

17
// 更新时自动填充
18
@Override
19
public void updateFill(MetaObject metaObject) {
20
this.strictUpdateFill(metaObject, "updateTime", LocalDateTime::now, LocalDateTime.class);
21
}
22
}

1
# 已迁移至上方全局 mybatis-plus.global-config.db-config 统一配置
2
# SpringBoot3 推荐全局配置，无需单独注解配置，统一规范

1
│
2
▼

1
│
2
┌───────┴───────┐
3
│ │
4
▼ ▼

1
（select） （delete）
2
│ │
3
▼ ▼

1
where delete_fiag=0 delete → update set delete_fiag=1
2
│ │
3
└───────┬───────┘
4
│
5
▼

1
import com.baomidou.mybatisplus.annotation.DbType;
2
import com.baomidou.mybatisplus.extension.plugins.MybatisPlusInterceptor;
3
import com.baomidou.mybatisplus.extension.plugins.inner.OptimisticLockerInnerInterceptor;
4
import com.baomidou.mybatisplus.extension.plugins.inner.PaginationInnerInterceptor;
5
import org.springframework.context.annotation.Bean;
6
import org.springframework.context.annotation.Configuration;

1
/**
2
* SpringBoot3 专属 MP 插件配置类
3
* 兼容3.x版本，无过时方法、无依赖冲突
4
*/
5
@Configuration
6
public class MpConfig {
7

8
/**
9
* 注册MP核心插件：分页插件 + 乐观锁插件
10
*/
11
@Bean
12
public MybatisPlusInterceptor mybatisPlusInterceptor() {
13
MybatisPlusInterceptor interceptor = new MybatisPlusInterceptor();
14
// 分页插件（适配MySQL8+）
15
interceptor.addInnerInterceptor(new PaginationInnerInterceptor(DbType.MYSQL));
16
// 乐观锁插件
17
interceptor.addInnerInterceptor(new OptimisticLockerInnerInterceptor());
18
return interceptor;
19
}
20
}

1
@Test
2
void testPage() {
3
// 参数1：当前页，参数2：每页条数
4
Page<User> page = new Page<>(1, 2);
5
// 分页查询条件
6
LambdaQueryWrapper<User> wrapper = new LambdaQueryWrapper<>();
7
wrapper.gt(User::getAge, 18);
8

9
Page<User> userPage = userMapper.selectPage(page, wrapper);
10

11
// 分页结果参数
12
System.out.println("当前页：" + userPage.getCurrent());
13
System.out.println("每页条数：" + userPage.getSize());
14
System.out.println("总条数：" + userPage.getTotal());
15
System.out.println("总页数：" + userPage.getPages());
16
System.out.println("数据列表：" + userPage.getRecords());
17
}

1
ALTER TABLE `user` ADD COLUMN `version` int DEFAULT 1 COMMENT '乐观锁版本号';

1
@Version
2
private Integer version;

1
interceptor.addInnerInterceptor(new OptimisticLockerInnerInterceptor());

1
└─────────┘ └────┬─────┘
2
│ │

1
│◀────────────────────┘
2
│
3
▼

1
│
2
▼

1
│
2
▼

1
│ │

1
│ │
2
▼ ▼

1
┌─────────────┐ ┌─────────────────────┐ ┌─────────────────┐

1
└─────────────┘ └─────────────────────┘ └────────┬────────┘
2
│
3
▼
4
┌─────────────┐ ┌─────────────────────┐ ┌─────────────────┐

1
└──────┬──────┘ └─────────────────────┘ └─────────────────┘
2
│
3
▼

1
┌─────────────┐ ┌─────────────────────┐ ┌─────────────────┐

1
└─────────────┘ └─────────────────────┘ └─────────────────┘