如何将包裹在通用实体类型中的实体主体发送到 Spring API

Question

我有几个子实体要发送到具有单独 API 请求的单个 API 端点，因此我将它们包装在父实体中并按如下方式发送。

主要包装类

@Getter
@Setter
public class ProfileUpdateRequest<T> {

  private T t;

  public void add(T t) {
    this.t = t;
  }

  public T get() {
    return t;
  }
}

@Getter
@Setter
public class EmailPreferencesUpdateRequest {
  @JsonProperty
  private boolean isAgreedToEmails;
}

@Getter
@Setter
public class AddressUpdateRequest {
  private List<UserAddress> addresses;
}

发送更新电子邮件首选项请求

  @RequestMapping(value = "/update-email", method = RequestMethod.POST, headers = "Accept=*/*", produces = "application/json")
  @ResponseBody
  public String updateEmailNotificationPreferences(@RequestBody EmailPreferencesUpdateRequest emailPreferencesUpdateRequest,
                                                    HttpServletRequest request) {

    ProfileUpdateRequest<EmailPreferencesUpdateRequest> updateRequest = new ProfileUpdateRequest<>();
    updateRequest.add(emailPreferencesUpdateRequest);
    UriComponents uri = UriComponentsBuilder
                .fromHttpUrl(baseUrl + "/user/update")
                .build();
    String urlString = uri.toUriString();
    HttpHeaders requestHeaders = new HttpHeaders();
    RestTemplate restTemplate = new RestTemplate();

    HttpEntity<ProfileUpdateRequest> requestWithHeader = new HttpEntity<>(updateRequest, requestHeaders);
    restTemplate.exchange(urlString, HttpMethod.PUT, requestWithHeader, UserEntry.class);
  return "success";
}

发送更新地址请求

   @RequestMapping(value = "/update-addresses", method = RequestMethod.POST, headers = "Accept=*/*", produces = "application/json")
   @ResponseBody
   public String updateAddresses(@RequestBody List<UserAddress> userAddresses, HttpServletRequest request) {

      AddressUpdateRequest addressUpdateRequest = new AddressUpdateRequest();
      addressUpdateRequest.setAddresses(userAddresses);
      ProfileUpdateRequest<AddressUpdateRequest> updateRequest = new ProfileUpdateRequest<>();
      updateRequest.add(addressUpdateRequest);
      UriComponents uri = UriComponentsBuilder
                .fromHttpUrl(baseUrl + "/user/update")
                .build();
      String urlString = uri.toUriString();
      HttpHeaders requestHeaders = new HttpHeaders();
      RestTemplate restTemplate = new RestTemplate();
      HttpEntity<ProfileUpdateRequest> requestWithHeader = new HttpEntity<>(updateRequest, requestHeaders);
      restTemplate.exchange(urlString, HttpMethod.PUT, requestWithHeader, UserEntry.class);
  return "success";
}

API 端点

@Path("/user/update")
@PUT
public UserEntry updateUser(ProfileUpdateRequest profileUpdateRequest) {
   if (profileUpdateRequest.get() instanceof AddressUpdateRequest) {
        // update addresses
    } else if (profileUpdateRequest.get() instanceof EmailPreferencesUpdateRequest) {
        // update emails
    }
}

从端点，我需要获取ProfileUpdateRequest类型中的实体，并检查实例我包装的实体类型，以便我可以传递给相关操作。 但我把它当作一个 LinkedHashMap。 如何解决这个问题？

Answer 1

有2种方式——

1. 如果工作正常，则将 profileUpdateRequest.get() 转换为 Object 之一，否则您将收到异常，然后转换为另一个。

2. 您的linkedHashMap 将包含对象中的字段，即对于EmailPreferencesUpdateRequest，它将包含一个像“isAgreedToEmails”这样的键，使用if else 检查映射，然后使用ObjectMapper 执行以下操作-

   EmailPreferencesUpdateRequest emailRequest = new ObjectMapper().readValue(YourMap, EmailPreferencesUpdateRequest.class);