How to Decode a xml Sent over Url in java

I am firing a online xml in java to the method below:

 public String WriteToServer(String xml) {
        StringBuilder answer = new StringBuilder();
        try {


         String myurl="example.com";
           //
            URL url = new URL(myurl);

          URLConnection conn = url.openConnection(Proxy.NO_PROXY);



           conn.setDoOutput(true);
            OutputStreamWriter writer = new OutputStreamWriter(conn.getOutputStream());

            writer.write(xml);
          writer.flush();

                BufferedReader reader = new BufferedReader(new InputStreamReader(conn.getInputStream()));
                   String line;
            while ((line = reader.readLine()) != null) {
                   answer.append(line);
                                }
          writer.close();
            reader.close();

        } catch (Exception e) {
          System.out.println(e);
        }
        return answer.toString();
    }

My Problem is that the server receives a encoded xml so it cant understand and returns a 500 response to the client. How can I decode the xml to a plain text that the server can read?