java - SpringBoot RestController generic POST type -

i'm experimenting building microservices using spring boot.

i have back-end api receives responseentity post requests , processes (saving database etc). data object of self-created class.

now have top-level api (that handles authentication,..). end-users communicate back-end services through top-level api. api has forward requests right back-end api's.

in top api don't want need include classes (e.g. data class in case) , rather send string json data or something. tried this:

@requestmapping(method = requestmethod.post, value="/data")     responseentity<string> createunit(@requestbody string data) {         uri uri = util.getserviceurl("dataservice");         string url = uri.tostring() + "/data";          responseentity<string> result = resttemplate.postforentity(url, data, string.class);         return new responseentity<string>(result.getbody(), httpstatus.ok);     } 

but results in org.springframework.web.client.httpclienterrorexception: 415 unsupported media type.

so question is, there way forward these requests back-end without need include object classes in api? figured should able since same when web-browser sends requests in json format without knowing kind of object data is.

the back-end handling looks this:

@requestmapping(method = requestmethod.post, value="/data") responseentity<data> savedata(@requestbody data data) {     //some code processes data     return new responseentity<data>(dataprocessed, httpstatus.ok); } 

when posting string backend service have specify content-type header spring knows httpmessageconverter use deserialize data object.

with resttemplate can specify header this:

httpheaders headers = new httpheaders(); headers.setcontenttype(mediatype.application_json);  httpentity<string> entity = new httpentity<string>(data, headers); resttemplate.postforentity(url, entity, responsetype);