How to Build a Reusable CRUD BaseController with MyBatis‑Plus in Spring Boot

Step 1 – Add MyBatis‑Plus Dependency

Include the Maven artifact com.baomidou:mybatis-plus-boot-starter:3.4.2 in pom.xml to bring MyBatis‑Plus into the Spring Boot project.

Step 2 – Utility Class ApprenticeUtil

This class supplies three reusable helpers: humpToLine(String str) converts camel‑case to snake_case by matching uppercase letters with a Pattern and inserting an underscore before each, then lower‑casing the result. lineToHump(String str) performs the reverse conversion by matching _(\w) and capitalising the captured character. getQueryWrapper(E entity) uses reflection to iterate over all non‑final fields of entity, builds a QueryWrapper<E>, and adds an eq condition for each non‑null field, converting the field name to snake_case via humpToLine.

Additional overloaded methods getValueForClass demonstrate how to retrieve a specific property value via JavaBeans PropertyDescriptor and Spring's ReflectionUtils, handling NoSuchFieldException and IntrospectionException.

Step 3 – Generic BaseController<S extends IService<E>, E>

The controller is annotated with Spring MVC and Swagger annotations and injects the generic service S baseService. It defines the following endpoints, each delegating to the corresponding IService method and wrapping the result with ResponseUtils.success(...): @PostMapping("/insert") –

baseService.save(entity)

@PostMapping("/deleteById")

–

baseService.removeByIds(ids)

@PostMapping("/updateById")

–

baseService.updateById(entity)

@GetMapping("/getById")

–

baseService.getById(id)

@PostMapping("/save")

–

baseService.saveOrUpdate(entity)

@PostMapping("/list")

– builds a QueryWrapper via ApprenticeUtil.getQueryWrapper(entity) and returns baseService.list(queryWrapper). @PostMapping("/page") – validates page (minimum 1) and size (maximum 100), constructs a Page<E>, applies optional ascending/descending order fields from PageParamDto, and returns baseService.page(page, queryWrapper). @PostMapping("/count") – uses the same QueryWrapper to call baseService.count(queryWrapper).

Step 4 – Enable Pagination

MyBatis‑Plus does not enable pagination by default. Register a PaginationInnerInterceptor for MySQL in a configuration class:

@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

Concrete controllers inherit from BaseController and specify the service interface and entity type. No additional CRUD code is required.

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

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

Project Source

Full source code is available at:

https://gitee.com/WangFuGui-Ma/mybatis-plus-pro