以下是一个基于 Spring Boot 和 MyBatis-Plus 的简单项目代码示例，实现基础的 CRUD 功能：

项目结构

src/main/java/com/example/demo
├── config
│   └── MybatisPlusConfig.java
├── controller
│   └── UserController.java
├── entity
│   └── User.java
├── mapper
│   └── UserMapper.java
├── service
│   ├── UserService.java
│   └── impl
│       └── UserServiceImpl.java
└── DemoApplication.java

添加依赖 (pom.xml)

<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>3.5.3.1</version>
    </dependency>
    
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <scope>runtime</scope>
    </dependency>
</dependencies>

实体类 (User.java)

@Data
@TableName("user")
public class User {
    @TableId(type = IdType.AUTO)
    private Long id;
    private String name;
    private Integer age;
    private String email;
}

Mapper 接口 (UserMapper.java)

@Repository
public interface UserMapper extends BaseMapper<User> {
}

Service 层

public interface UserService extends IService<User> {
}

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

Controller 层 (UserController.java)

@RestController
@RequestMapping("/user")
public class UserController {
    @Autowired
    private UserService userService;

    @GetMapping("/{id}")
    public User getById(@PathVariable Long id) {
        return userService.getById(id);
    }

    @PostMapping
    public boolean save(@RequestBody User user) {
        return userService.save(user);
    }

    @PutMapping
    public boolean update(@RequestBody User user) {
        return userService.updateById(user);
    }

    @DeleteMapping("/{id}")
    public boolean delete(@PathVariable Long id) {
        return userService.removeById(id);
    }

    @GetMapping("/list")
    public List<User> list() {
        return userService.list();
    }
}

配置类 (MybatisPlusConfig.java)

@Configuration
@MapperScan("com.example.demo.mapper")
public class MybatisPlusConfig {
    @Bean
    public MybatisPlusInterceptor mybatisPlusInterceptor() {
        MybatisPlusInterceptor interceptor = new MybatisPlusInterceptor();
        interceptor.addInnerInterceptor(new PaginationInnerInterceptor(DbType.MYSQL));
        return interceptor;
    }
}

主启动类 (DemoApplication.java)

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

数据库配置 (application.yml)

spring:
  datasource:
    url: jdbc:mysql://localhost:3306/test?useSSL=false&serverTimezone=UTC
    username: root
    password: 123456
    driver-class-name: com.mysql.cj.jdbc.Driver

mybatis-plus:
  configuration:
    log-impl: org.apache.ibatis.logging.stdout.StdOutImpl

这个示例包含了 MyBatis-Plus 的基本配置和使用，实现了用户数据的增删改查功能。可以根据实际需求进一步扩展和完善。