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[英]Spring Boot: @GetMapping with Pageable as request parameter don't work as expected
[英]Pageable + @Query + JOIN (fetch?) in Spring Data don't work
我正在嘗試使用來自 Spring 數據的@Query
注釋在連接字段上將排序與Pageable
集成。
第一個接口的方法(沒有@Query
但有Pageable
)就像一個魅力。 就像當我只使用@Query
獲取一個 Employee 但不是Pageable
我在那里使用Optional<Employee>
(第三種方法)時一樣。 但是,當我嘗試將這兩者合而為一時,樂趣就開始了——它不再起作用了。
當我嘗試按name
字段對數據進行排序時,它會出現以下錯誤:
Caused by: org.hibernate.QueryException: could not resolve property: name of: (....).model.employee.Employee
所以問題是:如何告訴 spring 在連接字段中查找name
? 如何使用 Spring 數據執行此操作?
我已經嘗試了幾件事,但它們沒有用,或者我仍然不知道如何正確使用它們:
countQuery
添加到@Query
參數中,這樣這在某種程度上與分頁相對應( spring 數據 jpa @query 和可分頁)countQuery
但我更願意堅持使用Page<Employee>
而不是List<Employee>
。我將在下面留下一些代碼示例。 如果我遺漏了一些重要的東西,請隨時要求更新。
// Employee
@Entity
@Table(name = "employee", schema = "emp")
@Data
@NoArgsConstructor
public class Employee {
private static final String SEQUENCE = "EMPLOYEE_SEQUENCE";
@Id
@SequenceGenerator(sequenceName = SEQUENCE, name = SEQUENCE, allocationSize = 1)
@GeneratedValue(strategy = GenerationType.SEQUENCE, generator = SEQUENCE)
private Long id;
@Column(name = "employee_number")
private String employeeNumber;
@Column
@Enumerated(EnumType.STRING)
private EmployeeStatus status;
@OneToOne(fetch = FetchType.LAZY, cascade = CascadeType.ALL)
@Audited(targetAuditMode = RelationTargetAuditMode.NOT_AUDITED)
@JoinColumn(name = "id_details")
private Details details;
// some other fields ...
}
// Details
@Entity
@Table(name = "details", schema = "emp")
@Data
@NoArgsConstructor
public class Details {
private static final String SEQUENCE = "DETAILS_SEQUENCE";
@Id
@SequenceGenerator(sequenceName = SEQUENCE, name = SEQUENCE, allocationSize = 1)
@GeneratedValue(strategy = GenerationType.SEQUENCE, generator = SEQUENCE)
private Long id;
private String name;
private String surname;
// some other fields ...
}
// EmployeeDTO
@NoArgsConstructor
@AllArgsConstructor
@Data
@Builder(toBuilder = true)
public class EmployeeDTO {
private Long id;
private String employeeNumber;
private String status;
private String name;
private String surname;
// some other fields ...
}
// EmployeeRepository
@Repository
public interface EmployeeRepository extends JpaRepository<Employee, Long> {
// 1st method
Page<Employee> findByStatus(EmployeeStatus status, Pageable pageable);
// 2nd method
@Query(value = "select e from Employee e join e.details where e.status = :status",
countQuery = "select count(*) from Employee e join e.details where e.status = :status")
Page<Employee> getEmployeeDetails(@Param("status") EmployeeStatus status, Pageable pageable);
// 3rd method
@Query("select e from Employee e join fetch e.details where e.id = :id")
Optional<Employee> findByIdWithDetails(Long id);
// ...
}
// EmployeeService
@Service
public class EmployeeService {
private final EmployeeRepository employeeRepository;
private final EntityDtoConverter entityDtoConverter;
@Autowired
public EmployeeService(EmployeeRepository employeeRepository, EntityDtoConverter entityDtoConverter) {
this.employeeRepository = employeeRepository;
this.entityDtoConverter = entityDtoConverter;
}
public EmployeeResponse getEmployeesByStatus(EmployeeStatus status, int pageSize, int pageIndex, Sort.Direction sortDirection, String sortColumn) {
Page<EmployeeDTO> employeePage = employeeRepository.findByStatus(status, PageRequest.of(pageIndex, pageSize, Sort.by(sortDirection, sortColumn)))
.map(entityDtoConverter::convertEmployeeBaseToDto);
return new EmployeeResponse(employeePage);
}
public EmployeeResponse getEmployeeDetails(EmployeeStatus status, int pageSize, int pageIndex, Sort.Direction sortDirection, String sortColumn) {
Page<EmployeeDTO> employeePage = employeeRepository.getEmployeeDetails(status, PageRequest.of(pageIndex, pageSize, Sort.by(sortDirection, sortColumn)))
.map(entityDtoConverter::convertToEmployeeWithDetailsDto);
return new EmployeeResponse(employeePage);
}
// ...
}
// EntityDtoConverter
@Component
public class EntityDtoConverter {
public EmployeeDTO convertEmployeeBaseToDto(Employee entity) {
return EmployeeDTO.builder()
.id(entity.getId())
.employeeNumber(entity.getEmployeeNumber())
.status(entity.getStatus())
.build();
}
public EmployeeDTO convertToEmployeeWithDetailsDto(Employee entity) {
return convertEmployeeBaseToDto(entity).toBuilder()
.name(entity.getDetails().getName())
.surname(entity.getDetails().getSurname())
.build();
}
// ...
}
這是我的rest controller的方法之一:
@GetMapping
public ResponseEntity<EmployeeResponse> getEmployeesByStatus(EmployeeStatus status, int pageSize, int pageIndex, String sortDirection, String sortColumn) {
try {
EmployeeResponse employeeResponse = employeeService.getEmployeesByStatus(status, pageSize, pageIndex, Sort.Direction.fromString(sortDirection), sortColumn);
return employeeResponse.getTotalElements().equals(0L) ? ResponseEntity.noContent().build() : ResponseEntity.ok(employeeResponse);
} catch (Exception e) {
log.error(ERROR_MESSAGE, e);
return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR).build();
}
}
試試下面的代碼。
Specification<Employee> joins = (employee, query, cb) -> {
Join<Employee, Detail> details = employee.join("details");
return cb.and(
employee.equal(employee.get("name", name)),
details.equal(details.get("name", detailName))
);
};
PageRequest pageRequest = new PageRequest(0, 2, new Sort(Sort.Direction.DESC, "name"));
Page<Employee> customerPage = employeeRepository.findAll(joins, pageRequest);
這里我們試圖通知 JPA 這個名字是 Employee 表的外鍵。
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