How I can do this in a thread ?

public class GetXmlTask extends AsyncTask<String, Void, String> {
     @Override
     protected String doInBackground(String...urls) {
         String url = urls[0]; // Might want to handle more here
         return getXmlFromUrl(url);
     }

     @Override
     protected void onPostExecute(String result) {
       // This runs on the ui thread when done, put your logic that works
       // on the result here
     }

     @Override
     protected void onPreExecute() {
     }

     @Override
     protected void onProgressUpdate(Void... values) {
     }

     private String getXmlFromUrl(String url) {
             String xml = null;

             try {
                 // defaultHttpClient
                 DefaultHttpClient httpClient = new DefaultHttpClient();
                 HttpPost httpPost = new HttpPost(url);

                 HttpResponse httpResponse = httpClient.execute(httpPost);
                 HttpEntity httpEntity = httpResponse.getEntity();
                 xml = EntityUtils.toString(httpEntity);

             }
             catch (UnsupportedEncodingException e) {
                 e.printStackTrace();
             }
             catch (ClientProtocolException e) {
                 e.printStackTrace();
             }
             catch (IOException e) {
                 e.printStackTrace();
             }
             // return XML
             return xml;
         }
 }