Java 如何从JSON对象获取特定变量？

我试图从其他API获取一些数据，我需要从JSON对象获取StatusCode，但我得到的是null对象

我试图用StatusCode变量创建新类，但我得到了null。 我正在尝试获取以下数据：

Data(data=[{"Number":"20450143160505","DateCreated":"11-06-2019 10:14:27","DocumentWeight":0.5,"CheckWeight":0,"SumBeforeCheckWeight":0,"PayerType":"Recipient","RecipientFullName":"","RecipientDateTime":"","ScheduledDeliveryDate":"12-06-2019","PaymentMethod":"Cash","CargoDescriptionString":"","CargoType":"Parcel","CitySender":"Сокільники","CityRecipient":"Київ","WarehouseRecipient":"Відділення №150 (до 30 кг): вул. Антоновича, 43 (м.\"Олімпійська\")","CounterpartyType":"PrivatePerson","Redelivery":1,"RedeliverySum":"","RedeliveryNum":"","RedeliveryPayer":"","AfterpaymentOnGoodsCost":"","ServiceType":"WarehouseWarehouse","UndeliveryReasonsSubtypeDescription":"","WarehouseRecipientNumber":150,"LastCreatedOnTheBasisNumber":"","LastCreatedOnTheBasisDocumentType":"","LastCreatedOnTheBasisPayerType":"","LastCreatedOnTheBasisDateTime":"","LastTransactionStatusGM":"","LastTransactionDateTimeGM":"","WarehouseRecipientInternetAddressRef":"916c7c93-8460-11e4-acce-0050568002cf","MarketplacePartnerToken":"","DateScan":"12:23 12.06.2019","ClientBarcode":"","SenderAddress":"","RecipientAddress":"","CounterpartySenderDescription":"","CounterpartyRecipientDescription":"","CounterpartySenderType":"Organization","PaymentStatus":"","PaymentStatusDate":"","AmountToPay":"","AmountPaid":"","WarehouseRecipientRef":"916c7c94-8460-11e4-acce-0050568002cf","DocumentCost":40,"AnnouncedPrice":"","OwnerDocumentNumber":"","DateFirstDayStorage":"2019-06-21","InternationalDeliveryType":"","DaysStorageCargo":"","RecipientWarehouseTypeRef":"841339c7-591a-42e2-8233-7a0a00f0ed6f","StorageAmount":"","StoragePrice":"","VolumeWeight":"0.50","SeatsAmount":"1","OwnerDocumentType":"","ActualDeliveryDate":"2019-06-12 12:23:22","DateReturnCargo":"","CardMaskedNumber":"","Status":"Прибув у відділення","StatusCode":"7","RefEW":"8ed817ef-8c18-11e9-91ff-0025b501a04b","RedeliveryPaymentCardRef":"","RedeliveryPaymentCardDescription":"","CreatedOnTheBasis":"","DatePayedKeeping":"2019-06-21 00:00:00","OnlineCreditStatusCode":"","OnlineCreditStatus":""}])

获取数据的方法：

RestTemplate RestTemplate=新的RestTemplate； 数据字符串=restTemplate.postForObjectblalba，blabla，Data.class 我的班级呢

公共类数据{ @JsonPropertydata 私有JsonNode数据； //准备好 }

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有几种方法可以实现这一目标：

使用地图 您可以将响应负载读取为映射：

ParameterizedTypeReference响应类型= 新的参数化类型引用{}； 映射响应payload= restTemplate.exchangepurchaseRequestDetailsEndpoint，HttpMethod.POST， 新的HttpEntityrequestPayload、responseType； 字符串statusCode=responsePayload.getStatusCode； 仅映射所需的属性 定义映射所需属性的类：

@资料 @JsonIgnorePropertiesignoreUnknown=true 公共类响应payload{ @JsonPropertyStatusCode 私有字符串状态码； } 并使用上面定义的类读取响应有效负载：

ResponsePayload ResponsePayload= restemplate.postForObjecturi、请求、响应payload.class； 字符串statusCode=responsePayload.getStatusCode； 或者，您可以映射所需的属性，并将其余属性存储在映射中：

@资料 公共类响应payload{ @JsonPropertyStatusCode 私有字符串状态码； @JSONANYSETER 私有映射属性=新HashMap； @杰索尼奥雷 公共对象getString键{ 返回properties.getkey； } }

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您可能应该用一些有意义的东西替换blalba。当我在restTemplate.postForObjecturi、request、responseType中使用第一种方法时，iw得到：无法解析方法'postForObjectjava.lang.String，java.lang.String，org.springframework.core.ParameterizedTypeReference’当我使用你的第二种方式时，我会得到null@khззззЯзЯзЯЯзЯ。改用exchange。我的答案已相应更新。