第java中如何判斷JSONObject是否存在某個(gè)Key目錄判斷JSONObject是否存在某個(gè)Key檢查json字符串中是否存在該key下面介紹我自己的情況

判斷JSONObject是否存在某個(gè)Key

JSONObjectjsonObj=newJSONObject();

jsonObj.put("version","1.0.0");//版本號

jsonObj.put("encoding","UTF-8");//編碼方式

判斷jsonObject是否存在vesion屬性

jsonObj.has("version");

//返回true

檢查json字符串中是否存在該key

初衷，是由于工作需要，兩個(gè)單位需要接口數(shù)據(jù)對接，單位一需要發(fā)送json數(shù)據(jù)串到單位二，然而單位一發(fā)送的json數(shù)據(jù)中的字段不確定，聽他們解釋說，客戶在系統(tǒng)上輸那些字段，他們就會把那些字段帶過來，然后那些客戶不輸入的字段，他們就會默認(rèn)不帶。單位一要求單位二，將這種檢測出不帶的字段默認(rèn)值為空！

所以作為單位二，我們就需要想辦法檢測到單位一哪些字段沒帶過來。起初立馬想到的辦法就是用異常情況處理，因?yàn)槌绦虮旧頊y試的時(shí)候就報(bào)notfound了，所以用異常處理情有可原吧。。。如果用異常的，想了一下只能捕捉到notfound之后，在finally里將捕捉到的這個(gè)字段直接置空就ok了。

那么問題來了，對異常的情況試了一下，finally太多不好處理；所以就想了用另外一個(gè)方法，用json的一個(gè)containsKey()函數(shù)來判斷json串中是否存在這個(gè)key，即是否存在這個(gè)字段；當(dāng)然，還有其他函數(shù)也可以判斷的，這個(gè)根據(jù)自己引入的json包了。

下面介紹我自己的情況

導(dǎo)入的jar包為：

首先我導(dǎo)入的json包：

importnet.sf.json.JSONArray;

importnet.sf.json.JSONObject;

代碼如下：

/**

*9903接口解析json數(shù)據(jù)并且將數(shù)據(jù)進(jìn)行入庫

*@authorsyp

*@time2025年7月3日11:49:02

publicStringdateRepository(StringjsonData){

Log4jB("開始處理入庫程序!");

ReadConfig.PullConfigXml();//啟動配置文件

DBUtilsdb=newDBUtils();

JSONObjectjson=newJSONObject();

StringjsonStr=jsonData.substring(44,jsonData.length());

JSONObjectjsonObject=JSONObject.fromObject(jsonStr);

JSONObjectjsonCard=jsonObject.getJSONObject("cardid_info")

JSONObjectjsonObu=jsonObject.getJSONObject("obu_info");

JSONObjectjsonUser=jsonObject.getJSONObject("user_info");

JSONObjectjsonCar=jsonObject.getJSONObject("car_info");

//準(zhǔn)備將所有json數(shù)據(jù)信息入開卡集合表ETC_OPEN_CARD_COLLECTION

JSONObjectjsonAccno=jsonObject.getJSONObject("accno_info");

StringallSql="insertintoETC_OPEN_CARD_COLLECTION(ACCOUNTID,LINKMOBILE,ACCNO_USERNAME,CERTSN,POSID,GENTIME,TRX_SERNO,EMPLOYEEID,ORG_TRX_SERNO,CARD_ID,CARDTYPE,CARD_BRAND,CARD_MODEL,AGENCYID,CARD_USERID,VEHICLEID,ENABLETIME,EXPIRETIME,ISSUEDTYPE,CHANNELID,ISSUEDTIME,CARD_STATUS,STATUSCHANGETIME,CARD_OPERATION,OBU_ID,OBU_BRAND,OBU_MODEL,OBU_USERID,OBU_VEHICLEID,OBU_ENABLETIME,OBU_EXPIRETIME,REGISTEREDTYPE,REGISTEREDCHANNELID,REGISTEREDTIME,INSTALLTYPE,INSTALLCHANNELID,INSTALLTIME,OBU_STATUS,OBU_STATUSCHANGETIME,OBU_OPERATION,USER_ID,USERTYPE,USER_NAME,USERIDTYPE,USERIDNUM,USER_TEL,USER_ADDRESS,USER_REGISTEREDTYPE,USER_CHANNELID,USER_REGISTEREDTIME,DEPARTMENT,AGENTNAME,AGENTIDTYPE,AGENTIDNUM,USER_STATUS,USER_STATUSCHANGETIME,USER_OPERATION,CAR_ID,CAR_TYPE,CAR_USERID,OWNERNAME,OWNERIDTYPE,OWNERIDNUM,OWNERTEL,CAR_ADDRESS,CAR_CONTACT,CAR_REGISTEREDTYPE,CAR_CHANNELID,CAR_REGISTEREDTIME,VEHICLETYPE,VEHICLEMODEL,USECHARACTER,VIN,ENGINENUM,REGISTERDATE,ISSUEDATE,FILENUM,APPROVEDCOUNT,TOTALMASS,MAINTENANCEMASS,PERMITTEDWEIGHT,OUTSIDEDIMENSIONS,PERMITTEDTOWWEIGHT,TESTRECORD,WHEELCOUNT,AXLECOUNT,AXLEDISTANCE,AXISTYPE,CAR_OPERATION)values('"

+(jsonAccno.containsKey("accountid")jsonAccno.getString("accountid"):"")

+"','"

+(jsonAccno.containsKey("linkmobile")jsonAccno.getString("linkmobile"):"")

+"','"

+(jsonAccno.containsKey("username")jsonAccno.getString("username"):"")

+"','"

+(jsonAccno.containsKey("certsn")jsonAccno.getString("certsn"):"")

+"','"

+(jsonAccno.containsKey("posid")jsonAccno.getString("posid"):"")

+"','"

+(jsonAccno.containsKey("gentime")jsonAccno.getString("gentime"):"")

+"','"

+(jsonAccno.containsKey("trx_serno")jsonAccno.getString("trx_serno"):"")

+"','"

+(jsonAccno.containsKey("employeeid")jsonAccno.getString("employeeid"):"")

+"','"

+(jsonAccno.containsKey("org_trx_serno")jsonAccno.getString("org_trx_serno"):"")

+"','"

+(jsonCard.containsKey("id")jsonCard.getString("id"):"")

+"','"

+(jsonCard.containsKey("cardType")jsonCard.getString("cardType"):"")

+"','"

+(jsonCard.containsKey("brand")jsonCard.getString("brand"):"")

+"','"

+(jsonCard.containsKey("model")jsonCard.getString("model"):"")

+"','"

+(jsonCard.containsKey("agencyId")jsonCard.getString("agencyId"):"")

+"','"

+(jsonCard.containsKey("userId")jsonCard.getString("userId"):"")

+"','"

+(jsonCard.containsKey("vehicleId")jsonCard.getString("vehicleId"):"")

+"','"

+(jsonCard.containsKey("enableTime")jsonCard.getString("enableTime"):"")

+"','"

+(jsonCard.containsKey("expireTime")jsonCard.getString("expireTime"):"")

+"','"

+(jsonCard.containsKey("issuedType")jsonCard.getString("issuedType"):"")

+"','"

+(jsonCard.containsKey("channelId")jsonCard.getString("channelId"):"")

+"','"

+(jsonCard.containsKey("issuedTime")jsonCard.getString("issuedTime"):"")

+"','"

+(jsonCard.containsKey("status")jsonCard.getString("status"):"")

+"','"

+(jsonCard.containsKey("statusChangeTime")jsonCard.getString("statusChangeTime"):"")

+"','"

+(jsonCard.containsKey("operation")jsonCard.getString("operation"):"")

+"','"

+(jsonObu.containsKey("id")jsonObu.getString("id"):"")

+"','"

+(jsonObu.containsKey("brand")jsonObu.getString("brand"):"")

+"','"

+(jsonObu.containsKey("model")jsonObu.getString("model"):"")

+"','"

+(jsonObu.containsKey("userId")jsonObu.getString("userId"):"")

+"','"

+(jsonObu.containsKey("vehicleId")jsonObu.getString("vehicleId"):"")

+"','"

+(jsonObu.containsKey("enableTime")jsonObu.getString("enableTime"):"")

+"','"

+(jsonObu.containsKey("expireTime")jsonObu.getString("expireTime"):"")

+"','"

+(jsonObu.containsKey("registeredType")jsonObu.getString("registeredType"):"")

+"','"

+(jsonObu.containsKey("registeredChannelId")jsonObu.getString("registeredChannelId"):"")

+"','"

+(jsonObu.containsKey("registeredTime")jsonObu.getString("registeredTime"):"")

+"','"

+(jsonObu.containsKey("installType")jsonObu.getString("installType"):"")

+"','"

+(jsonObu.containsKey("installChannelId")jsonObu.getString("installChannelId"):"")

+"','"

+(jsonObu.containsKey("installTime")jsonObu.getString("installTime"):"")

+"','"

+(jsonObu.containsKey("status")jsonObu.getString("status"):"")

+"','"

+(jsonObu.containsKey("statusChangeTime")jsonObu.getString("statusChangeTime"):"")

+"','"

+(jsonObu.containsKey("operation")jsonObu.getString("operation"):"")

+"','"

+(jsonUser.containsKey("id")jsonUser.getString("id"):"")

+"','"

+(jsonUser.containsKey("userType")jsonUser.getString("userType"):"")

+"','"

+(jsonUser.containsKey("userName")jsonUser.getString("userName"):"")

+"','"

+(jsonUser.containsKey("userIdType")jsonUser.getString("userIdType"):"")

+"','"

+(jsonUser.containsKey("userIdNum")jsonUser.getString("userIdNum"):"")

+"','"

+(jsonUser.containsKey("tel")jsonUser.getString("tel"):"")

+"','"

+(jsonUser.containsKey("address")jsonUser.getString("address"):"")

+"','"

+(jsonUser.containsKey("registeredType")jsonUser.getString("registeredType"):"")

+"','"

+(jsonUser.containsKey("channelId")jsonUser.getString("channelId"):"")

+"','"

+(jsonUser.containsKey("registeredTime")jsonUser.getString("registeredTime"):"")

+"','"

+(jsonUser.containsKey("department")jsonUser.getString("department"):"")

+"','"

+(jsonUser.containsKey("agentName")jsonUser.getString("agentName"):"")

+"','"

+(jsonUser.containsKey("agentIdType")jsonUser.getString("agentIdType"):"")

+"','"

+(jsonUser.containsKey("agentIdNum")jsonUser.getString("agentIdNum"):"")

+"','"

+(jsonUser.containsKey("status")jsonUser.getString("status"):"")

+"','"

+(jsonUser.containsKey("statusChangeTime")jsonUser.getString("statusChangeTime"):"")

+"','"

+(jsonUser.containsKey("operation")jsonUser.getString("operation"):"")

+"','"

+(jsonCar.containsKey("id")jsonCar.getString("id"):"")

+"','"

+(jsonCar.containsKey("type")jsonCar.getString("type"):"")

+"','"

+(jsonCar.containsKey("userId")jsonCar.getString("userId"):"")

+"','"+

(jsonCar.containsKey("ownerName")jsonCar.getString("ownerName"):"")

+"','"+

(jsonCar.containsKey("ownerIdType")jsonCar.getString("ownerIdType"):"")

+"','"+

(jsonCar.containsKey("ownerIdNum")jsonCar.getString("ownerIdNum"):"")

+"','"+

(jsonCar.containsKey("ownerTel")jsonCar.getString("ownerTel"):"")

+"','"+

(jsonCar.containsKey("address")jsonCar.getString("address"):"")

+"','"+

(jsonCar.containsKey("contact")jsonCar.getString("contact"):"")

+"','"+

(jsonCar.containsKey("registeredType")jsonCar.getString("registeredType"):"")

+"','"+

(jsonCar.containsKey("channelId")jsonCar.getString("channelId"):"")

+"','"+

(jsonCar.containsKey("registeredTime")jsonCar.getString("registeredTime"):"")

+"','"+

(jsonCar.containsKey("vehicleType")jsonCar.getString("vehicleType"):"")

+"','"+

(jsonCar.containsKey("vehicleModel")jsonCar.getString("vehicleModel"):"")

+"','"+

(jsonCar.containsKey("useCharacter")jsonCar.getString("useCharacter"):"")

+"','"+

(jsonCar.containsKey("VIN")jsonCar.getString("VIN"):"")

+"','"+

(jsonCar.containsKey("engineNum")jsonCar.getString("engineNum"):"")

+"','"+

(jsonCar.containsKey("registerDate")jsonCar.getString("registerDate"):"")

+"','"+

(jsonCar.containsKey("issueDate")jsonCar.getString("issueDate"):"")

+"','"+

(jsonCar.containsKey("fileNum")jsonCar.getString("fileNum"):"")

+"','"+

(jsonCar.containsKey("approvedCount")jsonCar.getString("approvedCount"):"")

+"','"+

(jsonCar.containsKey("totalMass")jsonCar.getString("totalMass"):"")

+"','"+

(jsonCar.containsKey("maintenanceMass")jsonCar.getString("maintenanceMass"):"")

+"','"+

(jsonCar.containsKey("permittedWeight")jsonCar.getString("permittedWeight"):"")

+"','"+

(jsonCar.containsKey("outsideDimensions")jsonCar.getString("outsideDimen