Spring Data Jpa-大小和页面的分页问题，​​也与pageNumber和pageSize没有关系

Question

我真的经历了很多链接，例如：Set default page size for JPA Pageable Object，花了数周的时间来确定解决此问题的方法。

我已经开发了 Spring Data Jpa分页 示例。

Employee.java

@Builder
@Data
@AllArgsConstructor
@NoArgsConstructor
@Entity
public class Employee implements Serializable{
    private static final long serialVersionUID = 1L;

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name="EMPLOYEE_ID")
    private Long employeeId;

    @Column(name="FIRST_NAME")
    private String firstName;

    @Column(name="LAST_NAME")
    private String lastName;

    @Column(name="EMAIL_ID")
    private String email;

    @Column(name="STATUS")
    private String status;
}

EmployeeRepository.java

public interface EmployeeRepository extends JpaRepository<Employee, Long>{
    Page<Employee> findByStatusOrderByFirstNameAsc(String status, Pageable pageable);
}

EmployeeService.java

public interface EmployeeService {
    public Page<Employee> findAllEmployees(Pageable pr, Integer page, Integer size, String sortParam, String dir);
}

EmployeeServiceImpl.java

@Service
public class EmployeeServiceImpl implements EmployeeService {
    @Autowired
    private EmployeeRepository employeeRepository;

    @Override
    public Page<Employee> findAllEmployees(Pageable pr, Integer page, Integer size, String sortParam, String dir) {
        Pageable pageable = null;

        if (page != null && size != null && sortParam != null && dir != null) {
            if (dir.equals("ASC"))
                pageable = PageRequest.of(page, size, Sort.by(sortParam).ascending());
            else if (dir.equals("DESC"))
                pageable = PageRequest.of(page, size, Sort.by(sortParam).descending());
        }else {
            pageable = pr;
        }

        return employeeRepository.findByStatusOrderByFirstNameAsc("A", pageable);
    }
}

EmployeeController.java

@RestController
@Api(tags = "Employees APIs")
@RequestMapping(path = "/employees")
public class EmployeeController {
    @Autowired
    private EmployeeService employeeService;

    @ApiOperation(value = "Get Employees By Pagination", nickname = "Find Employees")
    @ApiResponses(value = { @ApiResponse(code = 200, message = "200"),
            @ApiResponse(code = 500, message = "Internal Server Error") })
    @GetMapping()
    public ResponseEntity<Page<Employee>> getAllEmployeesPaginated(
            @RequestParam(required = false, value="page") Integer page, 
            @RequestParam(required = false, value = "size") Integer size,
            @RequestParam(required = false) String sortByParam,
            @RequestParam(required = false) String direction,
            Pageable pageable){

        Page<Employee> employeePage = employeeService.findAllEmployees(pageable, page, size, sortByParam, direction);
        return new ResponseEntity<>(employeePage, HttpStatus.OK);
    }
}

AppPaginationConfig.java

@Configuration
public class AppPaginationConfig extends RepositoryRestMvcConfiguration{
    public AppPaginationConfig(ApplicationContext context, ObjectFactory<ConversionService> conversionService) {
        super(context, conversionService);
    }

    @Override
    @Bean
    public HateoasPageableHandlerMethodArgumentResolver pageableResolver() {
        HateoasPageableHandlerMethodArgumentResolver resolver = super.pageableResolver();
        resolver.setPageParameterName("page");
        resolver.setSizeParameterName("size");
        resolver.setOneIndexedParameters(true);
        resolver.setFallbackPageable(PageRequest.of(0, 5));
        return resolver;
    }
}

当我不填充任何值时（请参见此处的屏幕截图：Unable to override defaults of Pagination in Spring Boot 2.1.5.RELEASE?），默认情况下为EmployeeController值，但是当我填充"size", "page"变量时，然后{ {1}}对象创建了我要发送的详细信息。看起来Pageable和"pageNumber"与"pageSize"和"size"无关。

Request1："page"

注意：它将覆盖默认值 页面请求[数字：0，大小4，类别：未排序]

Request2：http://localhost:8080/employees?page=0&size=4

注意：我看到可分页对象的默认值是 页面请求[number：0，size 5，sort：UNSORTED] ，它不会覆盖默认值。