Semantic Knowledge Graph query using SolrJ

[Pratik Patel <pr...@semandex.net>]

I am trying to use Semantic Knowledge Graph in my java based application.

I have a Semantic Knowledge Graph query which works fine if I trigger it
through browser using restlet client. Following is the query.

{
  "queries": [
    "foo:\"5a6127a7234e76473a816f1c\""
  ],
  "compare": [
    {
      "type": "bar",
      "limit": 30
    }
  ]}

Now, I want to trigger the same query through SolrJ client. I have tried
following code but it gives me an error

{"error":{"msg":"KnowledgeGraphHandler requires POST data","code":400}}

The code in java is

    SolrQuery request = new SolrQuery();
    request.setRequestHandler("/skg");
    request.setShowDebugInfo(true);
    request.setParam("wt", "json");
    request.setParam("json",
"{\"queries\":[\"foo:\\\"5a6127a7234e76473a816f1c\\\"\"],\"compare\":[{\"type\":\"bar\",\"limit\":30}]}");
    request.set("rows", 10);
    request.setParam("qf", "conceptname^10 tags^3 textproperty^2 file_text^4");
    try {
        QueryResponse response =
getStore().getEnvironment().getSolr().query(request,
SolrRequest.METHOD.POST);
        NamedList<Object> rsp = response.getResponse();

        ArrayList<SimpleOrderedMap<Object>> skg_resp =
(ArrayList<SimpleOrderedMap<Object>>) rsp.get("clusters");

        if (skg_resp != null) {

        }
    }

Any idea what is wrong here? Any pointer to documentation on how to
construct request for Semantic Knowledge Graph through solrJ would be very
helpful.

Thanks

Pratik