java webapi调采购入库单保存接口时json解析出错，麻烦总部.....

请总部老师指点下，我这里是什么问题，我刚做cloud接口开发不久，实在看不出来是什么问题，谢谢！
我在用java调用cloud webapi 采购入库单保存接口时，一直提示 “Field Key is 【FSupplierId】”，但是又不知道这个字段到底是有什么问题
具体错误信息如下：

response_error: {
"InnerExWrapper": {
"IsEmpty": false,
"Data": {

},
"HelpLink": null,
"Message": "调用的目标发生了异常。",
"Source": null,
"StackTrace": " 在 System.RuntimeMethodHandle.InvokeMethod(Object target, Object[] arguments, Signature sig, Boolean constructor)\r\n 在 System.Reflection.RuntimeMethodInfo.UnsafeInvokeInternal(Object obj, Object[] parameters, Object[] arguments)\r\n 在 System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)\r\n 在 Kingdee.BOS.ServiceFacade.KDServiceFx.ServiceExecutor.Execute(KDServiceContext context, ServiceType svcType, String[] paraValues, SerializerProxy serializeProxy, ServiceType beginMethod)",
"TargetSite": null,
"ExceptionType": "System.Reflection.TargetInvocationException, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089",
"InnerException": {
"IsEmpty": false,
"Data": {

},
"HelpLink": null,
"Message": "MapComplexProperty Field Error ：Field Key is 【FSupplierId】",
"Source": null,
"StackTrace": " 在 Kingdee.BOS.WebApi.FormService.WebApiServiceCall.ExecuteOperation(Context ctx, FormMetadata metadata, FormOperation op, String data)\r\n 在 Kingdee.BOS.WebApi.FormService.WebApiServiceCall.ExcuteSpecialOperation(Context ctx, String formId, String data, Int64 opId)\r\n 在 Kingdee.BOS.WebApi.ServicesStub.DynamicFormService.Save(String formid, String data)",
"TargetSite": null,
"ExceptionType": "System.Exception, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089",
"InnerException": null
}
},
"ClassName": "Kingdee.BOS.ServiceFacade.ServiceException",
"Message": "MapComplexProperty Field Error ：Field Key is 【FSupplierId】",
"Data": null,
"InnerException": null,
"HelpURL": null,
"StackTraceString": " 在 Kingdee.BOS.ServiceFacade.KDServiceFx.ServiceExecutor.Execute(KDServiceContext context, ServiceType svcType, String[] paraValues, SerializerProxy serializeProxy, ServiceType beginMethod)\r\n 在 Kingdee.BOS.ServiceFacade.KDServiceFx.ExecuteServiceModule.OnProcess(KDServiceContext context)\r\n 在 Kingdee.BOS.ServiceFacade.KDServiceFx.ModulePipeline.ExcuteRequest(KDServiceContext context)\r\n 在 Kingdee.BOS.ServiceFacade.KDServiceFx.RequestExcuteRuntime.BeginRquest(RequestExtractor requestExtractor, WebContext webCtx)\r\n 在 Kingdee.BOS.ServiceFacade.KDServiceFx.RequestExcuteRuntime.StartRequest(RequestExtractor requestExtractor, WebContext context)\r\n 在 Kingdee.BOS.ServiceFacade.KDServiceFx.KDSVCHandler.ExecuteRequest(WebContext ctx, RequestExtractor requestExtractor)\r\n 在 Kingdee.BOS.ServiceFacade.KDServiceFx.KDSVCHandler.ProcessRequestInternal(WebContext webCtx, RequestExtractor requestExtractor)",
"RemoteStackTraceString": null,
"RemoteStackIndex": 0,
"ExceptionMethod": "8\nExecute\nKingdee.BOS.ServiceFacade.KDServiceFx, Version=5.1.134.6, Culture=neutral, PublicKeyToken=null\nKingdee.BOS.ServiceFacade.KDServiceFx.ServiceExecutor\nSystem.String Execute(Kingdee.BOS.ServiceFacade.KDServiceFx.KDServiceContext, Kingdee.BOS.ServiceFacade.KDServiceFx.ServiceType, System.String[], Kingdee.BOS.ServiceFacade.SerializerProxy, Kingdee.BOS.ServiceFacade.KDServiceFx.ServiceType)",
"HResult": -2147467259,
"Source": "Kingdee.BOS.ServiceFacade.KDServiceFx",
"WatsonBuckets": null,
"_httpCode": 500
}

我的json字符串是：

{
"Creator": "demo",
"NeedUpDateFields": [],
"Model": {
"FID": 0,
"FBillTypeID": {
"FNUMBER": "RKD01_SYS"
},
"FBusinessType": "CG",
"FBillNo": "test001",
"FDate": "2016/1/19",
"FStockOrgId": {
"FNumber": "101.2"
},
"FStockDeptId": {
"FNumber": "BM000008"
},
"FPurchaseOrgId": {
"FNumber": "101.2"
},
"FPayOrgId": {
"FNumber": "101.2"
},
"FSupplierId": {
"FSupplierId": 0,
"FNumber": "VEN00002"
},
"FSupplyId": {
"FSupplierId": 0,
"FNumber": "VEN00002"
},
"STK_InStock__FInStockFin": {
"FSettleOrgId": {
"FNumber": "101.2"
},
"FSettleCurrId": {
"FNumber": "PRE001"
},
"FExchangeRate": 1
},
"STK_InStock__FInStockEntry": [
{
"FMaterialId": {
"FNumber": "1.01.110-0018.000"
},
"FUnitID": {
"FNumber": "Pcs"
},
"FStockId": {
"FNumber": "CK001"
},
"FStockStatusId": {
"FNumber": "KCZT01_SYS"
},
"FRealQty": 10,
"FNote": "WEBAPI导入到cloud"
},
{
"FMaterialId": {
"FNumber": "1.01.221-0062-000"
},
"FUnitID": {
"FNumber": "Pcs"
},
"FStockId": {
"FNumber": "CK001"
},
"FStockStatusId": {
"FNumber": "KCZT01_SYS"
},
"FRealQty": 20,
"FNote": "WEBAPI导入到cloud"
}
]
}
}