java - 使用 RestTemplate 对 REST API 调用中的对象列表做出空响应

Question

所以我正在开发一个 REST 客户端，它使用 REST API 来使用 Spring RestTemplate 获取 JSON 对象。因此，我收到 HTTP 200 OK 响应，但类对象内的列表(设备)为空。但会获取其他字段。当我使用 postman 执行相同的请求时，效果很好。这可能是什么原因？

RestTemplate 代码片段:

 RestTemplate restTemplate = new RestTemplate();
HttpHeaders requestHeaders = new HttpHeaders();
requestHeaders.add("Content-Type", "application/json");
requestHeaders.add("Authorization", "Bearer " + apiToken);
HttpEntity entity = new HttpEntity(requestHeaders);
ResponseEntity<CloverMerchant> response = restTemplate.exchange(getMerchantDetailsUrl, HttpMethod.GET, entity, CloverMerchant.class);
return response.getBody();

CloverMerchant 模型类:

private String id;
private String name;
private String website;
private boolean isBillable;
private CloverBusinessEquipments equipment;

// other relevant getters and setters

CloverBusinessEquipments 模型类:

private List<CloverBusinessEquipment> elements;

    public CloverBusinessEquipments() {
}

@JsonGetter("elements")
public List<CloverBusinessEquipment> getElements() {
    return elements;
}

CloverBusinessEquipment 模型类:

private String merchantId;
private String serialNumber;
private String equipmentCode;
private String equipmentCodeDesc;
private String provisionedDeviceType;
private boolean boarded;
private boolean provisioned;

// relevant getters and setters

来自 REST API 的预期响应 JSON:

{
  "id": "5ZTFCGXQKVZNA",
  "name": "xxxx",
  "website": "https://xxxx.io",
  "isBillable": false,
  "equipment": {
  "elements": [
    {
        "merchantId": "5ZTFCGXQKVZNA",
        "boarded": false,
        "provisioned": true,
        "serialNumber": "C030UQ71040182",
        "equipmentCode": "105J",
        "equipmentCodeDesc": "Clover Mini",
        "provisionedDeviceType": "MAPLECUTTER"
    },
    {
        "merchantId": "5ZTFCGXQKVZNA",
        "boarded": false,
        "provisioned": true,
        "serialNumber": "C050UQ75150054",
        "equipmentCode": "1297",
        "equipmentCodeDesc": "Clover Station 2018",
        "provisionedDeviceType": "GOLDENOAK"
       }
    ]
  }
}

Answer 1

您的模型不代表 JSON 响应。您试图在 JSON 的根级别查找带有键 "elements" 的 JSONObject，但实际上它位于 "equipment" 键之后的第二级。

变量 - private CloverBusinessEquipments Equipments; 应表示:

"equipment": {
    "elements": [
        {
            "merchantId": "5ZTFCGXQKVZNA",
            "boarded": false,
            "provisioned": true,
            "serialNumber": "C030UQ71040182",
            "equipmentCode": "105J",
            "equipmentCodeDesc": "Clover Mini",
            "provisionedDeviceType": "MAPLECUTTER"
        },
        {
            "merchantId": "5ZTFCGXQKVZNA",
            "boarded": false,
            "provisioned": true,
            "serialNumber": "C050UQ75150054",
            "equipmentCode": "1297",
            "equipmentCodeDesc": "Clover Station 2018",
            "provisionedDeviceType": "GOLDENOAK"
        }
    ]
}

但是您已经对 POJO 进行了建模，它认为 equipments 变量将如下所示:

"elements": 
        {
            "merchantId": "5ZTFCGXQKVZNA",
            "boarded": false,
            "provisioned": true,
            "serialNumber": "C030UQ71040182",
            "equipmentCode": "105J",
            "equipmentCodeDesc": "Clover Mini",
            "provisionedDeviceType": "MAPLECUTTER"
        }