Automate CRUD with a Generic BaseController in Spring Boot

Introduction

The article demonstrates how to build a generic BaseController in a Spring Boot project that automatically supplies common CRUD operations for any entity, leveraging MyBatis‑Plus and Java reflection.

Step 1 – Add MyBatis‑Plus Dependency

<dependency>
    <groupId>com.baomidou</groupId>
    <artifactId>mybatis-plus-boot-starter</artifactId>
    <version>3.4.2</version>
</dependency>

Include this Maven dependency in pom.xml to enable MyBatis‑Plus features.

Step 2 – Create ApprenticeUtil

This utility class provides reflection‑based helpers: humpToLine(String str) – converts camelCase to snake_case. lineToHump(String str) – converts snake_case to camelCase. <E> QueryWrapper<E> getQueryWrapper(E entity) – builds a QueryWrapper by iterating over non‑null fields of the given entity. <E> Object getValueForClass(E entity, String value) – obtains a field value via PropertyDescriptor and Spring’s ReflectionUtils.

public class ApprenticeUtil {
    private static Pattern humpPattern = Pattern.compile("[A-Z]");
    private static Pattern linePattern = Pattern.compile("_(\\w)");
    // ... (methods humpToLine, lineToHump, getQueryWrapper, getValueForClass)
}

Step 3 – Implement the Generic BaseController

The controller is defined with two generic parameters: S extends IService<E> for the service layer and E for the entity type. It provides the following endpoints: @PostMapping("/insert") –

insert(E entity)

@PostMapping("/deleteById")

–

delete(List<Integer> ids)

@PostMapping("/updateById")

–

updateById(E entity)

@GetMapping("/getById")

–

getById(Integer id)

@PostMapping("/save")

–

save(E entity)

@PostMapping("/list")

–

list(E entity)

@PostMapping("/page")

–

page(PageParamDto<E> dto)

@PostMapping("/count")

–

count(E entity)

public class BaseController<S extends IService<E>, E> {
    @Autowired
    protected S baseService;

    @PostMapping("/insert")
    public ResponseUtils insert(@RequestBody E entity) {
        baseService.save(entity);
        return ResponseUtils.success("添加成功");
    }
    // ... other CRUD methods as shown above
}

Step 4 – Configure Pagination Support

MyBatis‑Plus does not enable pagination by default, so a configuration class adds the PaginationInnerInterceptor for MySQL.

@Configuration
public class MybatisPlusConfig {
    @Bean
    public MybatisPlusInterceptor mybatisPlusInterceptor() {
        MybatisPlusInterceptor interceptor = new MybatisPlusInterceptor();
        interceptor.addInnerInterceptor(new PaginationInnerInterceptor(DbType.MYSQL));
        return interceptor;
    }
}

Step 5 – Extend BaseController in Concrete Controllers

For each domain object, create a controller that extends the generic base class, supplying the specific service interface and entity class.

@RestController
@RequestMapping("/apprentice/dynamic")
@Api("动态管理")
public class DynamicController extends BaseController<IDynamicService, Dynamic> {}

@RestController
@RequestMapping("/apprentice/blog")
@Api(tags = "博客管理")
public class BlogController extends BaseController<IBlogService, Blog> {}

These concrete controllers inherit all CRUD endpoints without additional code.

Conclusion

By combining MyBatis‑Plus, a reflection‑based utility, and a generic Spring MVC controller, developers can rapidly scaffold RESTful CRUD APIs for any entity, reduce boilerplate, and maintain a consistent API surface across the application.