How to get specyfic object from RestTemplate exchange method?

I have i end-point which return me this response

{
  "head": {
    "status": 200,
    "ok": true,
    "messages": [],
    "errors": [],
    "references": {}
  },
  "body": {
    "id": "d57a9c7aef9842c2e31a0f49c",
    "flowId": "f57979d06f9842c3e94f1f197",
    "creationDate": 1470744494732,
    "path": "/luafanti/test",
    "version": 0,
    "elems": {
      "xxx": {
        "type": "integer",
        "value": 200
      }
    }
  }
}

My question is, how to make a model who can populate only with part of my json response, for example with this

 "xxx": {
            "type": "integer",
            "value": 200
        }

or this

"elems": {
          "xxx": {
            "type": "integer",
            "value": 200
          }
        }