Send JSON-Object as POST in RequestBuilder

Send JSON-Object as POST in RequestBuilder

At client-side:

JSONArray devicedata=new JSONArray();

devicedata.set(0,"zero");

devicedata.set(1, "one");

devicedata.set(2, two);

try
{
 String url=localhost:8080/requestsend/servlet;

 RequestBuilder builder=new RequestBuilder(RequestBuilder.POST, url);

//adding the post data
 builder.setRequestData(devicedata.toString());

 builder.setCallback(new RequestCallback() 

{
 @Override
 public void onResponseReceived(Request request, Response response) 

{
  popup.setVisible(false);
  JSONValue value=JSONParser.parse(response.getText());
  JSONObject jobj=value.isObject();
  if(jobj.get("status").isString().stringValue().equalsIgnoreCase("success"))
    {

    }
  @Override
  public void onError(Request request, Throwable exception) 

  {
     Window.alert("Error occurred" + exception.getMessage());
  }
 });
builder.send();

}catch(Exception e)
{
}

At Server Side:

String s=req.getReader().readLine();
JSONArray jarray=new JSONArray(s);