AsyncTask to post to url returns null exception

Issue

I got this code elswhere on stackoverflow. It did not work for me from the beginning.

To stop initial errors I had to change

protected void doInBackground(String... params) {

to

protected String doInBackground(String... params) {

I keep returning an error but e.getmessage returns a null value.

public class CallAPI extends AsyncTask<String, String, String> {

public CallAPI(){
    //set context variables if required
}

@Override
protected void onPreExecute() {
    super.onPreExecute();
}


@Override

protected String doInBackground(String... params) {
    String urlString = params[0]; // URL to call

    String data = params[1]; //data to post

    OutputStream out = null;
    Log.i("doinbackground url=", urlString + data);


    try {

        URL url = new URL(urlString);

        HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();

        out = new BufferedOutputStream(urlConnection.getOutputStream());

        BufferedWriter writer = new BufferedWriter (new OutputStreamWriter(out, "UTF-8"));

        writer.write(data);

        writer.flush();

        writer.close();

        out.close();

        urlConnection.connect();


    } catch (Exception e) {

        String ErrorMessageJ = "Error message is NULL";
        if (e.getMessage() != null ){ErrorMessageJ = e.getMessage();}
        Log.i("doinbackground e", ErrorMessageJ);




    }
    return null;

}
}

Solution

You are returning null in your doInBackground check it

may be you need to Return some String in your doInBackground as per params of your AsyncTask

Answered By - AskNilesh