Spring解析数据json时如何处理空值

Question

我使用spring解析数据json，格式如下：

请求

 {
"fiSessionKey": "NiceTest_2021111723",
"fiCode": "B100000022",
"taskCode": "KYC_VR2_RQST",
"appNumber": "APPL000000000000999",
"customerNumber": "12345678",
"mobilePhoneNumber": "0988021309",
"infoProvConcent": "Y"
}

答复：

{
"appNumber": "APPL000000000000999",
"fiCode": "B100000022",
"taskCode": "KYC_VR2_RQST",
"customerNumber": "12345678",
"productCode": "S2028",
"infoProvConcent": "Y",
"niceSessionKey": "S202820220712182525939485",
"responseTime": "20220712182553",
"responseCode": "P000",
"responseMessage": "Normal - [20] Thông tin trong lịch sử",
"mobilePhoneNumber": "0988021309",
"result": [
    {
        "msisdn": "84865214351",
        "total_calls": 9,
        "total_durations": 305
    },
    {
        "msisdn": "84973853818",
        "total_calls": 7,
        "total_durations": 140
    }
]
}

这是我在课堂上的方法：

@RequestMapping("/api/v1/ccpCheck")
@ResponseBody
public ResponseEntity<ReturnMessage> checkCCPHistoryCustomerPoint(@RequestParam Map<String, Object> params, ModelMap model) throws Exception {

    ReturnMessage message = new ReturnMessage();
    RestTemplate restTemplate = new RestTemplate();

    String url = "https://myserverIP:80/kyc/KYC_VR2_RQST";

    String token = AppConstants.FICODE;

    JSONObject jsonObject =  new JSONObject();
    JSONArray jsonArray =  new JSONArray();

    int recordSuccess = 0 , recordFail = 0;

    try {

        String fiSessionKey = "NiceTest_2021111723";
        String fiCode = "B100000022";
        String taskCode = "KYC_VR2_RQST";
        String appNumber = "APPL000000000000999";
        String customerNumber = "12345678";                 
        String mobilePhoneNumber = "0988021309";        
        String infoProvConcent = "Y";

        jsonObject.put("fiSessionKey", fiSessionKey);
        jsonObject.put("fiCode", fiCode);
        jsonObject.put("taskCode", taskCode);
        jsonObject.put("appNumber", appNumber);
        jsonObject.put("customerNumber", customerNumber);
        jsonObject.put("mobilePhoneNumber", mobilePhoneNumber);
        jsonObject.put("infoProvConcent", infoProvConcent);
        jsonArray.put(jsonObject);    

         jsonArray.put(jsonObject);
         System.out.println("params -> {}" + jsonObject);             

        HttpHeaders headers = new HttpHeaders();
        headers.add("token", token);
        headers.add("Content-Type", "application/json; charset=utf-8");

        HttpEntity<String> entity = new HttpEntity<String>(jsonObject.toString(), headers);
        String result = restTemplate.postForObject(url, entity, String.class);

        LOGGER.debug("============================log result begin==========================================");
        LOGGER.debug(result);
        LOGGER.debug("header    : "     + entity.getHeaders());
        LOGGER.debug("body      : "     + entity.getBody());
        LOGGER.debug("=======================log result end=================================================");

在调用API之后，解析数据，下一步将按行归属消息插入数据。然后循环获取列表中的数据

        try {

            if(result != null && !result.isEmpty()) {

                ObjectMapper mapper = new ObjectMapper();
                mapper.configure(DeserializationFeature.ACCEPT_SINGLE_VALUE_AS_ARRAY, true);

                @SuppressWarnings("unchecked")
                List<Map<String, Object>> listSendMessage = mapper.readValue(result, List.class);

                for(int i=0 ; i < listSendMessage.size() ; i++) {

                    Map<String, Object> dataSend = (Map<String, Object>)  listSendMessage.get(i);
                    // Map<String, Object> sendMessage = (Map<String, Object>) dataSend.get("result");

                    System.out.println("================================");
                    System.out.println(dataSend);

                    Map <String, Object> saveParams = new HashMap<String, Object>();

                    saveParams.put("customerNumber", dataSend.get("customerNumber"));
                    saveParams.put("responseTime", dataSend.get("responseTime"));

                    saveParams.put("msisdn", dataSend.get("msisdn"));
                    saveParams.put("total_calls", dataSend.get("total_calls"));
                    saveParams.put("total_durations", dataSend.get("total_durations"));

                    saveParams.put("mobilePhoneNumber", dataSend.get("mobilePhoneNumber"));
                    saveParams.put("infoProvConcent", dataSend.get("infoProvConcent"));
                    saveParams.put("appNumber", dataSend.get("appNumber"));
                    saveParams.put("productCode", dataSend.get("productCode"));
                    saveParams.put("taskCode", dataSend.get("taskCode"));
                    saveParams.put("responseTime", dataSend.get("responseTime"));
                    saveParams.put("responseMessage", dataSend.get("responseMessage"));
                    saveParams.put("responseCode", dataSend.get("responseCode"));
                    saveParams.put("fiCode", dataSend.get("fiCode"));
                    saveParams.put("fiSessionKey", dataSend.get("fiSessionKey"));

                    System.out.println(saveParams);

                    int resultInsert = 0;

                    resultInsert = cCPHistoryService.insert_KYC_VR2_RQST(saveParams);

                    LOGGER.info("Result Inserting -> {}: " + resultInsert);
                }
                /*
                Map<String, Object> mapFromString = new HashMap<String, Object>();
                mapFromString = mapper.readValue(result, HashMap.class);

                @SuppressWarnings("unchecked")
                Map<String, Object> saveParameter = (Map<String, Object>) mapFromString.get("result");

                System.out.println(saveParameter);

                System.out.println(sendMessage);
                Map <String, Object> saveParams = new HashMap<String, Object>();

                saveParams.put("customerNumber", sendMessage.get("customerNumber"));
                saveParams.put("responseTime", sendMessage.get("responseTime"));
                saveParams.put("msisdn", sendMessage.get("msisdn"));

                System.out.println(saveParams);*/

            }
            else {
                message.setMessage("There are " + recordFail + "fail");
                return ResponseEntity.ok(message);
            }
        }
        catch(Exception e) {
            message.setMessage(e.toString());
            e.printStackTrace();
            return ResponseEntity.ok(message);
        }
        message.setMessage("There are " + recordSuccess + "successul");
        return ResponseEntity.ok(message);
    }
    catch (HttpClientErrorException exception) {
        // TODO Auto-generated catch block
        org.springframework.http.HttpStatus status = exception.getStatusCode();         
    }
    catch (JSONException e) {           
        e.printStackTrace();
        return ResponseEntity.ok(message);
    }
}

当我运行此方法时，我可以从json数据中获取结果，但只有3个字段无法获取值，并且为null：

 msisdn=null
 total_calls=null
 total_durations=null

如何获得msisdn、total\u调用、total\u循环持续时间的值？非常感谢

Answer 1

你可以用更好的方式来做，但我不知道完整的要求，所以不能多加评论，但是在解决方案中，你实现的dataSend对象包含结果数据作为映射，键作为结果，因此如果你尝试下面的方法，它将为你所需的标记提供结果，其余的你可以根据你的要求实现-

Map<String, Object> saveParams = new HashMap<String, Object>();
List<Map<String,Object>> resultList = (List<Map<String, Object>>) dataSend.get("result");
                System.out.println(resultList);
                for (Map<String, Object> map:resultList                         ) {
                   System.out.println(map.get("msisdn"));
                   System.out.println(map.get("total_calls"));
                   System.out.println(map.get("total_durations"));
                }