C# Standalone HTTP Json Rpc

CSharp_JsonRpc.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Text;
using System.Threading.Tasks;
using System.Web;
using System.Threading;
using Newtonsoft.Json;
using AustinHarris.JsonRpc;

namespace HttpJsonRPC
{
    class Program
    {
        class ExampleCalculatorService : JsonRpcService
        {
            [JsonRpcMethod]
            private double add(double l, double r)
            {
                return l + r;
            }
        }

        static object obj = new ExampleCalculatorService();

        static void Main(string[] args)
        {
            var listener = new HttpListener();
            listener.Prefixes.Add("http://*:8080/");
            listener.Start();

            var httpRequestHandle = new Func<HttpListenerRequest, string>((request) => {
                var task = JsonRpcProcessor.Process(request.QueryString["j"]);
                return task.Result;
            });

            while (true)
            {
                ThreadPool.QueueUserWorkItem(
                    (c) => {
                        var context = c as HttpListenerContext;
                        var request = context.Request;
                        var response = context.Response;

                        try
                        {
                            string responseText = httpRequestHandle(request);
                            byte[] buf = Encoding.UTF8.GetBytes(responseText);
                            response.ContentLength64 = buf.Length;
                            response.OutputStream.Write(buf, 0, buf.Length);
                        }
                        catch(Exception ex)
                        {
                            Console.WriteLine(ex.Message);
                        }
                        finally
                        {
                            response.OutputStream.Close();
                        }

                    }
                    , listener.GetContext());
            }
        }
    }
}