Java 用于列出转换问题的MapStruct页
我不熟悉Spring和MapStruct。我在从页面转换到列表时遇到问题。我在服务中使用了MapStruct映射器。我需要从DB获取所有产品，然后使用MapStruct mapper转换为Java 用于列出转换问题的MapStruct页,java,spring-boot,dto,mapstruct,Java,Spring Boot,Dto,Mapstruct,我不熟悉Spring和MapStruct。我在从页面转换到列表时遇到问题。我在服务中使用了MapStruct映射器。我需要从DB获取所有产品，然后使用MapStruct mapper转换为ProductResponse，然后返回PagedResponse对象，但出现以下错误： java.lang.ClassCastException: org.springframework.data.domain.PageImpl cannot be cast to java.util.List at
ProductResponsePagedResponsejava.lang.ClassCastException: org.springframework.data.domain.PageImpl cannot be cast to java.util.List
at org.walana.GP.service.ProductService.getAll(ProductService.java:67) ~[classes/:na]
at org.walana.GP.controller.ProductController.getAll(ProductController.java:40)
@Entity
@Table(name = "replace_numbers")
public class ReplaceNumber extends UserDateAudit
{
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
@NotBlank
@Size(max = 20)
private String partNumber;
@ManyToOne(fetch = FetchType.LAZY, optional = false)
@JoinColumn(name = "product_id", nullable = false)
private Product product;
public ReplaceNumber() {}
public ReplaceNumber(String partNumber)
{
this.partNumber = partNumber;
}
}
@Mapper(componentModel = "spring")
public interface ProductMapper
{
ProductResponse toProductResponse(Product product);
List<ProductResponse> toProductResponses(List<Product> products);
Product toProduct(ProductResponse productResponse);
}
@RestController
@RequestMapping("/api/products")
public class ProductController
{
@Autowired
private ProductService productService;
private static final Logger logger = LoggerFactory.getLogger(ProductController.class);
@GetMapping
public PagedResponse<ProductResponse> getAll(@CurrentUser UserPrincipal currentUser,
@RequestParam(value = "page", defaultValue = AppConstants.DEFAULT_PAGE_NUMBER) int page,
@RequestParam(value = "size", defaultValue = AppConstants.DEFAULT_PAGE_SIZE) int size)
{
return productService.getAll(currentUser, page, size);
}
}
public class ReplaceNumberResponse
{
private Long id;
private String partNumber;
}
public class ProductResponse
{
private Long id;
private String partNumber;
private String description;
private List<ReplaceNumberResponse> replaceNumberResponses;
private ProductManufacturerResponse manufacturer;
private ProductModelResponse model;
private ProductCategoryResponse category;
private float cost;
private float price;
}
public class PagedResponse<T>
{
private List<T> content;
private int page;
private int size;
private long totalElements;
private int totalPages;
private boolean last;
public PagedResponse() {
}
public PagedResponse(List<T> content, int page, int size, long totalElements, int totalPages, boolean last) {
this.content = content;
this.page = page;
this.size = size;
this.totalElements = totalElements;
this.totalPages = totalPages;
this.last = last;
}
}
@Service
public class ProductService
{
@Autowired
ProductRepository productRepository;
@Autowired
ProductMapper productMapper;
public PagedResponse<ProductResponse> getAll(UserPrincipal currentUser, int page, int size)
{
Pageable pageable = PageRequest.of(page, size, Sort.Direction.DESC, "createdAt");
Page<Product> products = productRepository.findAll(pageable);
if (products.getNumberOfElements() == 0)
{
return new PagedResponse<>(Collections.emptyList(), products.getNumber(),
products.getSize(), products.getTotalElements(), products.getTotalPages(), products.isLast());
}
List<ProductResponse> productResponses = productMapper.toProductResponses((List<Product>) products);
return new PagedResponse<>(productResponses, products.getNumber(),
products.getSize(), products.getTotalElements(), products.getTotalPages(), products.isLast());
}
}
@Entity
@Table(name = "products", indexes = {@Index(name= "part_number_index", columnList = "part_number", unique = true)})
public class Product extends UserDateAudit
{
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
@NotBlank
@Column(name = "part_number", nullable = false)
@Size(max = 20)
private String partNumber;
@NotBlank
@Size(max = 255)
private String description;
@OneToMany(
mappedBy = "product",
cascade = CascadeType.ALL,
fetch = FetchType.EAGER,
orphanRemoval = true
)
@Fetch(FetchMode.SELECT)
private List<ReplaceNumber> replaceNumbers = new ArrayList<>();
@ManyToOne
@JoinColumn(name = "product_manufacturer_id", referencedColumnName = "id")
private ProductManufacturer manufacturer;
@ManyToOne
@JoinColumn(name = "product_model_id", referencedColumnName = "id")
private ProductModel model;
@ManyToOne
@JoinColumn(name = "product_category_id", referencedColumnName = "id")
private ProductCategory category;
@Column(name = "cost", nullable = false)
@DecimalMin(message = "Cost should be greater than 1", value = "1")
private float cost;
@Column(name = "price", nullable = false)
@DecimalMin(message = "Price should be greater than 0", value = "0")
private float price;
}
@实体
@表（name=“products”，Index={@Index（name=“part\u number\u Index”，columnList=“part\u number”，unique=true）}）
公共类产品扩展了UserDateAudit
{
@身份证
@GeneratedValue（策略=GenerationType.IDENTITY）
私人长id；
@不空白
@列（name=“part\u number”，null=false）
@尺寸（最大值=20）
私有字符串部件号；
@不空白
@尺寸（最大值=255）
私有字符串描述；
@独身癖(
mappedBy=“产品”，
cascade=CascadeType.ALL，
fetch=FetchType.EAGER，
孤立删除=真
)
@Fetch（FetchMode.SELECT）
private List replaceNumber=new ArrayList（）；
@许多酮
@JoinColumn（name=“产品\制造商\标识”，referencedColumnName=“标识”）
私人产品制造商；
@许多酮
@JoinColumn（name=“product\u model\u id”，referencedColumnName=“id”）
私人产品模型；
@许多酮
@JoinColumn（name=“product\u category\u id”，referencedColumnName=“id”）
私人产品类别；
@列（name=“cost”，nullable=false）
@小数点（message=“成本应大于1”，value=“1”）
私人浮动成本；
@列（name=“price”，nullable=false）
@小数点（message=“价格应大于0”，value=“0”）
私人浮动价格；
}
public class ReplaceNumberResponse
{
private Long id;
private String partNumber;
}
public class ProductResponse
{
private Long id;
private String partNumber;
private String description;
private List<ReplaceNumberResponse> replaceNumberResponses;
private ProductManufacturerResponse manufacturer;
private ProductModelResponse model;
private ProductCategoryResponse category;
private float cost;
private float price;
}
public class PagedResponse<T>
{
private List<T> content;
private int page;
private int size;
private long totalElements;
private int totalPages;
private boolean last;
public PagedResponse() {
}
public PagedResponse(List<T> content, int page, int size, long totalElements, int totalPages, boolean last) {
this.content = content;
this.page = page;
this.size = size;
this.totalElements = totalElements;
this.totalPages = totalPages;
this.last = last;
}
}
@Service
public class ProductService
{
@Autowired
ProductRepository productRepository;
@Autowired
ProductMapper productMapper;
public PagedResponse<ProductResponse> getAll(UserPrincipal currentUser, int page, int size)
{
Pageable pageable = PageRequest.of(page, size, Sort.Direction.DESC, "createdAt");
Page<Product> products = productRepository.findAll(pageable);
if (products.getNumberOfElements() == 0)
{
return new PagedResponse<>(Collections.emptyList(), products.getNumber(),
products.getSize(), products.getTotalElements(), products.getTotalPages(), products.isLast());
}
List<ProductResponse> productResponses = productMapper.toProductResponses((List<Product>) products);
return new PagedResponse<>(productResponses, products.getNumber(),
products.getSize(), products.getTotalElements(), products.getTotalPages(), products.isLast());
}
}
公共类ProductResponse
{
私人长id；
私有字符串部件号；
私有字符串描述；
私有列表替换编号响应；
私人产品制造商或响应制造商；
私有产品模型响应模型；
私人产品类别响应类别；
私人浮动成本；
私人浮动价格；
}
@Entity
@Table(name = "replace_numbers")
public class ReplaceNumber extends UserDateAudit
{
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
@NotBlank
@Size(max = 20)
private String partNumber;
@ManyToOne(fetch = FetchType.LAZY, optional = false)
@JoinColumn(name = "product_id", nullable = false)
private Product product;
public ReplaceNumber() {}
public ReplaceNumber(String partNumber)
{
this.partNumber = partNumber;
}
}
@Mapper(componentModel = "spring")
public interface ProductMapper
{
ProductResponse toProductResponse(Product product);
List<ProductResponse> toProductResponses(List<Product> products);
Product toProduct(ProductResponse productResponse);
}
@RestController
@RequestMapping("/api/products")
public class ProductController
{
@Autowired
private ProductService productService;
private static final Logger logger = LoggerFactory.getLogger(ProductController.class);
@GetMapping
public PagedResponse<ProductResponse> getAll(@CurrentUser UserPrincipal currentUser,
@RequestParam(value = "page", defaultValue = AppConstants.DEFAULT_PAGE_NUMBER) int page,
@RequestParam(value = "size", defaultValue = AppConstants.DEFAULT_PAGE_SIZE) int size)
{
return productService.getAll(currentUser, page, size);
}
}
@Mapper（componentModel=“spring”）
公共接口ProductMapper
{
ProductResponse到ProductResponse（产品）；
列出TopProductResponses（列出产品）；
产品到产品（ProductResponse ProductResponse）；
}
public class ReplaceNumberResponse
{
private Long id;
private String partNumber;
}
public class ProductResponse
{
private Long id;
private String partNumber;
private String description;
private List<ReplaceNumberResponse> replaceNumberResponses;
private ProductManufacturerResponse manufacturer;
private ProductModelResponse model;
private ProductCategoryResponse category;
private float cost;
private float price;
}
public class PagedResponse<T>
{
private List<T> content;
private int page;
private int size;
private long totalElements;
private int totalPages;
private boolean last;
public PagedResponse() {
}
public PagedResponse(List<T> content, int page, int size, long totalElements, int totalPages, boolean last) {
this.content = content;
this.page = page;
this.size = size;
this.totalElements = totalElements;
this.totalPages = totalPages;
this.last = last;
}
}
@Service
public class ProductService
{
@Autowired
ProductRepository productRepository;
@Autowired
ProductMapper productMapper;
public PagedResponse<ProductResponse> getAll(UserPrincipal currentUser, int page, int size)
{
Pageable pageable = PageRequest.of(page, size, Sort.Direction.DESC, "createdAt");
Page<Product> products = productRepository.findAll(pageable);
if (products.getNumberOfElements() == 0)
{
return new PagedResponse<>(Collections.emptyList(), products.getNumber(),
products.getSize(), products.getTotalElements(), products.getTotalPages(), products.isLast());
}
List<ProductResponse> productResponses = productMapper.toProductResponses((List<Product>) products);
return new PagedResponse<>(productResponses, products.getNumber(),
products.getSize(), products.getTotalElements(), products.getTotalPages(), products.isLast());
}
}
公共类页面响应
{
私有列表内容；
私人网页；
私有整数大小；
私有长元素；
私人网页；
私有布尔最后；
公共页面响应（）{
}
公共页面响应（列表内容、整型页面、整型大小、长型totalElements、整型totalPages、布尔型last）{
this.content=内容；
this.page=page；
这个。大小=大小；
this.totalElements=totalElements；
this.totalPages=totalPages；
this.last=last；
}
}
public class ReplaceNumberResponse
{
private Long id;
private String partNumber;
}
public class ProductResponse
{
private Long id;
private String partNumber;
private String description;
private List<ReplaceNumberResponse> replaceNumberResponses;
private ProductManufacturerResponse manufacturer;
private ProductModelResponse model;
private ProductCategoryResponse category;
private float cost;
private float price;
}
public class PagedResponse<T>
{
private List<T> content;
private int page;
private int size;
private long totalElements;
private int totalPages;
private boolean last;
public PagedResponse() {
}
public PagedResponse(List<T> content, int page, int size, long totalElements, int totalPages, boolean last) {
this.content = content;
this.page = page;
this.size = size;
this.totalElements = totalElements;
this.totalPages = totalPages;
this.last = last;
}
}
@Service
public class ProductService
{
@Autowired
ProductRepository productRepository;
@Autowired
ProductMapper productMapper;
public PagedResponse<ProductResponse> getAll(UserPrincipal currentUser, int page, int size)
{
Pageable pageable = PageRequest.of(page, size, Sort.Direction.DESC, "createdAt");
Page<Product> products = productRepository.findAll(pageable);
if (products.getNumberOfElements() == 0)
{
return new PagedResponse<>(Collections.emptyList(), products.getNumber(),
products.getSize(), products.getTotalElements(), products.getTotalPages(), products.isLast());
}
List<ProductResponse> productResponses = productMapper.toProductResponses((List<Product>) products);
return new PagedResponse<>(productResponses, products.getNumber(),
products.getSize(), products.getTotalElements(), products.getTotalPages(), products.isLast());
}
}
@服务
公共类产品服务
{
@自动连线
产品库产品库；
@自动连线
ProductMapper ProductMapper；
公共页面响应getAll（UserPrincipal currentUser，int page，int size）
{
Pageable Pageable=PageRequest.of（page，size，Sort.Direction.DESC，“createdAt”）；
Page products=productRepository.findAll（可分页）；
if（products.getNumberOfElements（）==0）
{
返回新的PagedResponse（Collections.emptyList（）、products.getNumber（），
products.getSize（）、products.getTotalElements（）、products.getTotalPage（）、products.isLast（））；
}
List productResponses=productMapper.toProductResponses（（列表）产品）；
返回新的PagedResponse（productResponses，products.getNumber（），
products.getSize（）、products.getTotalElements（）、products.getTotalPage（）、products.isLast（））；
}
}
@Entity
@Table(name = "replace_numbers")
public class ReplaceNumber extends UserDateAudit
{
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
@NotBlank
@Size(max = 20)
private String partNumber;
@ManyToOne(fetch = FetchType.LAZY, optional = false)
@JoinColumn(name = "product_id", nullable = false)
private Product product;
public ReplaceNumber() {}
public ReplaceNumber(String partNumber)
{
this.partNumber = partNumber;
}
}
@Mapper(componentModel = "spring")
public interface ProductMapper
{
ProductResponse toProductResponse(Product product);
List<ProductResponse> toProductResponses(List<Product> products);
Product toProduct(ProductResponse productResponse);
}
@RestController
@RequestMapping("/api/products")
public class ProductController
{
@Autowired
private ProductService productService;
private static final Logger logger = LoggerFactory.getLogger(ProductController.class);
@GetMapping
public PagedResponse<ProductResponse> getAll(@CurrentUser UserPrincipal currentUser,
@RequestParam(value = "page", defaultValue = AppConstants.DEFAULT_PAGE_NUMBER) int page,
@RequestParam(value = "size", defaultValue = AppConstants.DEFAULT_PAGE_SIZE) int size)
{
return productService.getAll(currentUser, page, size);
}
}
@RestController
@请求映射（“/api/products”）
公共类产品控制器
{
@自动连线
私人产品服务；
私有静态最终记录器Logger=LoggerFactory.getLogger（ProductController.class）；
@GetMapping
公共页面响应getAll（@CurrentUser-UserPrincipal-CurrentUser，
@RequestParam（value=“page”，defaultValue=AppConstants.DEFAULT\u page\u NUMBER）int page，
@RequestParam（value=“size”，defaultValue=AppConstants.DEFAULT\u PAGE\u size）int size）
{
return productService.getAll（当前用户、页面、大小）；
}
}
productMapper.toProductResponses((List<Product>) products)