Spring WebClient PageImpl Content is missing field

如何解决Spring WebClient PageImpl Content is missing field

我尝试通过 WebClient 从另一个微服务检索页面。如果我直接向 Postman 请求此 MS，我会在页面内获得 content 的“类型”等信息。但是，如果我通过 webClient 请求 MS，“类型”将从 content（以及其他一些字段）中消失。内容是抽象类 account 的列表，其中“type”为 JsonSubTypes。
有人可以找到错误，为什么“类型”-属性。消失了？

回复

来自http://localhost:8080/api/v1/accounts

的回复

{
    "content": [
        {
            "type": "savingsBook","id": 108,"accountNumber": 99781944,...
        }
    ],"pageable": {
        ...
    },"totalPages": ...
    ...
}
    

来自http://localhost:8081/accounts

的回复

{
    "content": [
        {
            "id": 108,"totalPages": ...
    ...
}

代码片段：

8080 的帐户控制器

@RequestMapping(method = RequestMethod.GET,produces = "application/json")
public <T extends Account> Page<T> getAccounts(@RequestParam(value = "page",required = false) Integer page,@RequestParam(value = "pageSize",required = false) Integer pageSize,@RequestParam(value = "sortBy",required = false) String sortBy) {
    if (page == null) {
        page = 0;
    }
    if (pageSize == null) {
        pageSize = 10;
    }
    if (sortBy == null) {
        Page<T> p = accountService.getAccounts(page,pageSize);
        return new PageImpl<T>(p.getContent(),p.getPageable(),p.getTotalElements()) {};

    } else {
        Sort sort = Sort.by(sortBy);
        Page<T> p = accountService.getAccounts(page,pageSize,sort);
        return new PageImpl<T>(p.getContent(),p.getTotalElements()) {};
    }
}

8081 帐户控制器

@GetMapping
public  <T extends Account> Page<T> getAllAccounts(@RequestParam(value = "page",required = false) String sortBy) {   
     if (page == null) {
         page = 0;
     }
     if (pageSize == null) {
         pageSize = 10;
     }
     if (sortBy == null) {
         return accountService.getAllAccounts(page,pageSize);
     } else {
         return accountService.getAllAccounts(page,sortBy);
     }
}

8081 AccountService

public <T extends Account> Page<T> getAllAccounts(Integer pageNumber,Integer pageSize) {
    ParameterizedTypeReference<CustomPageImpl<T>> typeReference = new ParameterizedTypeReference<CustomPageImpl<T>>(){};
    System.out.println("Anfrage an: " + addr + "/accounts/");
    System.out.println(client.get().uri("/accounts/").retrieve().bodyToMono(typeReference).block().getContent());
    Page<T> prodData = (CustomPageImpl<T>)(client.get().uri("/accounts/").retrieve().bodyToMono(typeReference).block());
    return prodData;
}

CustomPageImpl（从另一个 StackOverflow-Post 获得）

public class CustomPageImpl<T> extends PageImpl<T> {
    private static final long serialVersionUID = 1L;

    @JsonCreator(mode = JsonCreator.Mode.PROPERTIES)
    public CustomPageImpl(@JsonProperty("content") List<T> content,@JsonProperty("number") int number,@JsonProperty("size") int size,@JsonProperty("totalElements") Long totalElements,@JsonProperty("pageable") JsonNode pageable,@JsonProperty("last") boolean last,@JsonProperty("totalPages") int totalPages,@JsonProperty("sort") JsonNode sort,@JsonProperty("first") boolean first,@JsonProperty("numberOfElements") int numberOfElements){
        super(content,PageRequest.of(number,size),totalElements);
    }
    public CustomPageImpl(List<T> content,Pageable pageable,long total) {
        super(content,pageable,total);
    }

    public CustomPageImpl(List<T> content) {
        super(content);
    }

    public CustomPageImpl() {
        super(new ArrayList<>());
    }
}
    

解决方法

我自己找到了这个问题的答案。

问题在于，Account 是抽象的并且具有 json 子类型。通过将 public class CustomPageImpl<T> extends PageImpl<T> 替换为 public class CustomPageImpl<T extends Account> extends PageImpl<T> 我能够解决这个问题。现在我按计划收到了类型。