Error 500 HttpUrlConnection java

Question

I was using AsyncHttpClient to make some requests to my database and It was working fine. But, when I tried to use 3g on my mobile, it simply didn't work. That's why I decided to change HttpClient to HttpUrlConnection (people said that it works better with 3g + wifi). But, when I was coding it, I just got stuck at a buffer problem that I can't solve. The code is:

public class SendPostRequest extends AsyncTask<String, Void, String>{
    String base64CredenciaisCodificadas;
    HashMap postDataParam;
    @Override
    protected String doInBackground(String... url) {
        String response = "";
        try{
            URL link = new URL(url[0]);
            HttpURLConnection e = (HttpURLConnection)link.openConnection();
            e.setReadTimeout(15000);
            e.setConnectTimeout(15000);
            e.setRequestMethod("POST");
            e.setRequestProperty("Authorization", "Basic " + base64CredenciaisCodificadas);
            e.setDoInput(true);
            e.setDoOutput(true);
            e.setFixedLengthStreamingMode(getPostDataString(postDataParam).length());
            OutputStream os = e.getOutputStream();
            BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(os, "UTF-8"));
            writer.write(getPostDataString(postDataParam));
            writer.flush();
            writer.close();
            os.close();
            int responseCode = e.getResponseCode();
            if (responseCode == 200){
                //Code to get data from web service.
            }
        } catch(Exception e){

        }
        return response;
    }
    private String getPostDataString(HashMap<String, String> params) throws UnsupportedEncodingException {
        StringBuilder result = new StringBuilder();
        boolean first = true;
        Iterator var4 = params.entrySet().iterator();

        while(var4.hasNext()) {
            Map.Entry entry = (Map.Entry)var4.next();
            if(first) {
                first = false;
                result.append("?");
            } else {
                result.append("&");
            }

            result.append(URLEncoder.encode((String)entry.getKey(), "UTF-8"));
            result.append("=");
            result.append(URLEncoder.encode((String)entry.getValue(), "UTF-8"));
        }

        return result.toString();
    }
}

And the error log is:

10-25 15:16:11.128 30807-30898/petma.testesappcarona I/System.out: Stat: 500; Msg: buffer(com.android.okhttp.internal.http.HttpConnection$UnknownLengthSource@834db8).inputStream()

If anyone has any more doubts, please just ask and I will send additional data.

Edit: It is android. It has permission to internet at manifest.

Answer 1

I managed the problem. It wasn't problem at the code. The web service I was trying to connect was only accessible through GET request. I switched the POST to GET and it now works!

But, there is now a new Problem: When switching to 3g, I get 403: Access forbidden. Any ideas?

Answer 2

Common reason: Steam is getting closed either by wrong parameters or by other unhandled exception.

Possible cause: HashMap postDataParam is never assigned in this code, due to which you are passing null in below code.

      e.setFixedLengthStreamingMode(
       getPostDataString(postDataParam).length());

And null parameter is causing com.android.okhttp.internal.http.HttpConnection$UnknownLengthSource@834db8).inputStream()

Free advice :

• Try to reuse the code wherever is possible example

  you could have stored getPostDataString(postDataParam) in some variable since its getting used twice in your code.
  

• If possible, use Retrofit for Network Calls.