无法使用泛型调用嵌套的 restTemplate Json

Question

我正在尝试调用 restTemplate 进行 API 测试。返回的 json 是多层嵌套。

{
  "code": 200,
  "data": {
    "result": {
      "publicId": "xyz"
    }
  }
}

我有以下 classes 作为包装器：

@JsonAutoDetect(fieldVisibility = JsonAutoDetect.Visibility.ANY)
public abstract class RestCallResponse<T> {

    private int code;

    protected RestCallResponse(int code) {
        this.code = code;
    }

    protected RestCallResponse(){}

    @JsonProperty("data")
    public Map<?, ?> getRestCallResponse() {
        return ImmutableMap.of("result", getResult());
    }

    @JsonIgnore
    protected abstract T getResult();

    public int getCode() {
        return code;
    }
}

然后 SuccessRestResponse class 扩展这个摘要 class :

@JsonAutoDetect(fieldVisibility = JsonAutoDetect.Visibility.NONE)
public class SuccessRestResponse<T> extends RestCallResponse<T> {

    @JsonProperty("result")
    private T result;

    public SuccessRestResponse() {

    }

    public SuccessRestResponse(T result) {
        super(HttpStatus.SC_OK);
        this.result = result;
    }

    protected T getResult() {
        return this.result;
    }

}

然后我终于有了实际的数据 POJO :

public final class CreatedResponse {
    @JsonProperty
    private final EntityId publicId;

    public CreateCreativeResponse(EntityId publicId) {
        this.publicId = publicId;
    }
}

在测试用例中，我这样调用：

ResponseEntity<SuccessRestResponse<CreatedResponse>> newResponse =
                restTemplate.exchange(requestEntity, new ParameterizedTypeReference<SuccessRestResponse<CreatedResponse>>() {});

但我收到以下错误：

nested exception is org.springframework.http.converter.HttpMessageNotReadableException: Could not read document: null value in entry: result=null (through reference chain: com.inmobi.helix.test.api.dao.SuccessRestResponse["data"]);

有什么建议吗？我哪里错了？

Answer 1

我通过变通方法解决了问题。仍然不知道上面的代码有什么问题。我摆脱了 class RestCallResponse<T> 并将 SuccessRestResponse<T> 中的字段成员编辑为如下所示：

@JsonAutoDetect(fieldVisibility = JsonAutoDetect.Visibility.ANY)
public class SuccessRestResponse<T> {

    private int code;
    private Map<String, T> data;

    public int getCode() {
        return code;
    }

    public void setCode(int code) {
        this.code = code;
    }

    public Map<String, T> getData() {
        return data;
    }

    @JsonIgnore
    public T getResult() {
        return data.get("result");
    }

    public void setData(Map<String, T> data) {
        this.data = data;
    }
}

这对应反序列化时的嵌套json。

P.S. - Would still like to know what went wrong in my above code though. As in, why did class hierarchy not work for me.

无法使用泛型调用嵌套的 restTemplate Json

Unable to make restTemplate call with Generics for nested Json

java

generics

jackson

resttemplate

spring-boot