Android Java - Call a WCF Rest Webservice with Post Request

Question

I'm tired of giving turns to something that seems so simple but it is not to give and have scoured all forums and tututiais .

I wanted to do in android a call to a WCF Rest WebService through POST requests .

In c# I can do it, sending the post , url and "body param" ."

But in android ( java ) when sending a parameter , the webservice method (although I can not connect ) , dizme that data as always invalid .

The code I have so far is this , which is the main connection method :

public void LoginWS(final String urlWS, final String user) throws Exception 
{
    Thread thread = new Thread(new Runnable() {
        @Override
        public void run() 
        {
            try 
            {
               //urlWS ="http://mywebsite/webservicename.svc/rest/methodnamePost";

                String inputCoded = Base64.encodeToString(user.getBytes("UTF-8"), Base64.NO_WRAP);
                HttpURLConnection request = (HttpURLConnection) new URL(urlWS).openConnection();

                try {
                    request.setDoOutput(true);
                    request.setDoInput(true);
                    request.setRequestProperty("Content-Type", "application/json");
                    request.setRequestMethod("POST");                        
                    request.connect();

                    InputStream is = request.getInputStream();
                    String resp = convertStreamToString(is);
                    byte[] data = Base64.decode(resp, Base64.NO_WRAP);
                    response = new String(data, "UTF-8");

                    is.close();


                } finally {
                    request.disconnect();
                }
            }
            catch (Exception ex)
            {
                ex.printStackTrace();
            }
        }
    });

    thread.start();
}

In the webservice side, the method signature is this:

[OperationContract]
[WebInvoke(Method = "POST", RequestFormat = WebMessageFormat.Json,      ResponseFormat = WebMessageFormat.Json)]
string methodnamePost(string input);

If someone can help me to understand how to send a POST request sending parameters without a name would be great.