Spring RestTemplate在尝试反序列化嵌套的对象列表时返回null对象

Posted 2021-03-27

所以这是我试图转换为Java bean的Json

我使用jackson将JSON绑定到我的数据对象

{
        "legend": {
            "id": "379ec5d8c",
            "name": "Stabil Koos",
            "payers": [{
                    "id": "ab1651df-b835-495558-a2a5-2e6d42f7a41e",
                    "ranking": 1,
                    "buyer": {
                        "id": "67a6359838-0fda-43a6-9e2b-51a7d399b6a1",
                        "nationality": "en",
                        "stats": {
                            "gameeCount": 16581,
                            "count": 99098
                        }
                    }
                },
                {
                    "id": "379ecw555d8c",
                    "ranking": 2,
                    "buyer": {
                        "id": "2b451d0eda-ab0c-4345660-be3f-6ba3bebf1f81",
                        "nationality": "no",
                        "stats": {
                            "gamerCount": 1182,
                            "count": 7113
                        }
                    }
                }
            ]
        }
}

我的豆子看起来像这样;

 public class League implements Serializable {

   private String id;
   private String name;
   @JsonUnwrapped
   private List<Payer> payers;

   // getters and setters

付款人豆：

  public class Payers implements Serializable {

      private String id;
      private long ranking;
      private Buyer buyer;

      // getters and setters

我在Junit中使用Rest Template和postForObject

@Before
public void beforeTest() {
    restTemplate = new RestTemplate();
    headers = new HttpHeaders();
    headers.setContentType(MediaType.APPLICATION_JSON);
    entity = new HttpEntity(REQUEST, headers);
}

我检索对象的最终代码是：

@Test
public void retrieveData() {
    League league = restTemplate.postForObject(ENDPOINT_URL, entity, League.class);
    System.out.println(legend);
}

答案

您显示的JSON是针对具有league属性的对象，该属性是League对象而不是联盟对象本身。您还需要一个额外的响应类：

class LeagueResponse {
  private League league;

  League getLeague() { return league; }
}

和：

LeagueResponse leagueResponse = restTemplate.postForObject(ENDPOINT_URL, entity, LeagueResponse.class);
League league = leagueResponse.getLeague();