No property * found for type entity!，SpringData JPA 中自定义存储库的问题，总结

末蓝、 2021-12-04 00:15 194阅读 0赞

## 问题出现，最近在学[QueryDSL][]时，起初搭好环境后，启动i项目一直报错，No property findOffEmpCust found for type CustomersEntity! ##

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQyMTA1NjI5_size_16_color_FFFFFF_t_70]

## 代码示例 ##

@Repository
    public interface CustomerRepo extends JpaRepository<CustomersEntity,Long>, JpaSpecificationExecutor<CustomersEntity>, CustomerRepoCustom {
    }

public interface CustomerRepoCustom {
    
        // 自定义返回
        public List<OffEmpCustVo> findOffEmpCust();
    
    }

public class CustomerRepoCustomImpl implements CustomerRepoCustom \{

@PersistenceContext
    private EntityManager em;
    
    @Override
    public List<OffEmpCustVo> findOffEmpCust() {
        JPAQuery<OffEmpCustVo> query = new JPAQuery<>(em);
    
        QCustomersEntity customers = QCustomersEntity.customersEntity;
        QOfficesEntity office = QOfficesEntity.officesEntity;
        QEmployeesEntity employee = QEmployeesEntity.employeesEntity;
    
        List<Tuple> list = query.select(
                office.officeCode,
                office.country.as("offCountry"),
                office.state.as("offState"),
                employee.employeeNumber.as("emploNumber"),
                employee.email.as("emploEmail"),
                customers.customerNumber.as("custNumber"),
                customers.state.as("custState")).from(office).leftJoin(employee).on(office.officeCode.eq(employee.officeCode)).leftJoin(customers).on(employee.employeeNumber.eq(customers.salesRepEmployeeNumber)).fetchResults().getResults();
    
        List<OffEmpCustVo> voList = list.stream().map(r -> JSONUtil.toBean(JSONUtil.toJsonStr(r), OffEmpCustVo.class)).collect(Collectors.toList());
    
        return voList;
    
        // select off.officeCode , off.country, off.state , em.employeeNumber, em.email, cu.customerNumber , cu.state  from offices off left outer join employees em on (off.officeCode=em.officeCode) left outer join customers cu on (em.employeeNumber=cu.salesRepEmployeeNumber)
    }

## 注意：上图是改后的目录结构，之前我的命名不是这样的，才会出错，总结一下，当需要自定义存储库，一定要和本身的存储库，名称一定要对应，还有自定义存储库的实现类命名一定要规范以Impl后缀，前以自定义存储库的名称前缀。 ##

[QueryDSL]: http://www.querydsl.com/
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQyMTA1NjI5_size_16_color_FFFFFF_t_70]: /images/20211203/2e1a688bbacf47df9bda4fb5172e586b.png