Parse JsonString to JsonObject in Java

I have the following String :

{
    "response": true,
    "model_original_id": "5acea0b5:1431fde5d6e:-7fff",
    "model_new_id": 500568,
    "model_new_version": 1,
    "reload": true,
    "idsModelProperties": [{
        "key": "creation_date",
        "value": "2013-12-23"
    },
    {
        "key": "state",
        "value": 1,
        "displayValue": "Analisi"
    }],
    "idsNodes": [],
    "idsConnectors": [],
    "idsNodesProperties": []
}

and i need to parse it as a JSONObject. I tried to use quickjson but it gives me an exception when it tries to parse an emty string . This is what i tried :

JsonParserFactory factory=JsonParserFactory.getInstance();
JSONParser parser=factory.newJsonParser();
Map jsonData=parser.parseJson(response_output);

Exception: Exception in thread "main" com.json.exceptions.JSONParsingException: @Key-Hierarchy::root/idsNodes[0]/ @Key:: Value is expected but found empty...@Position::256

Any idea?