Asynctask Doinbackground Returning A Nullpointerexception Only Sometimes

Getting this error: java.lang.RuntimeException: An error occured while executing doInBackground() at android.os.AsyncTask$3.done(AsyncTask.java:200) at java.util.concurrent.Future

Solution 1:

One thing that you are doing wrong is continuing to execute doInBackground after an error that makes it impossible to continue meaningfully. For instance:

try {
    response = client.execute(request);
} catch (ClientProtocolException e1) {
    // TODO Auto-generated catch block
    e1.printStackTrace();
} catch (IOException e1) {
    // TODO Auto-generated catch block
    e1.printStackTrace();
}

If this throws an exception, response is going to be null and there's no point in proceeding further. You'll generate a NullPointerException in the next block of code. That won't be fatal, because you are catching all exceptions there. Further on, though, this pattern repeats and you aren't catching all exceptions.

You should exit prematurely, returning null as the String result. Then you can test for a null in onPostExecute and let the user know what happened in a graceful way.