Question

I have a weird issue. I receive the following error that causes a force-close:

org.apache.harmony.xml.ExpatParser$ParseException: At line 1, column 0: no element found at org.apache.harmony.xml.ExpatParser.parseFragment(ExpatParser.java:508)
at org.apache.harmony.xml.ExpatParser.parseDocument(ExpatParser.java:467)
at org.apache.harmony.xml.ExpatReader.parse(ExpatReader.java:329)
at org.apache.harmony.xml.ExpatReader.parse(ExpatReader.java:286)

After clicking the Force Close button, the Activity is recreated and the parsing completes without a hitch. I’m using the following code snippet inside doInBackground of an AsyncTask:

URL serverAddress = new URL(url[0]);

HttpURLConnection connection = (HttpURLConnection) serverAddress.openConnection();
connection.setRequestMethod("GET");
connection.setDoOutput(true);
connection.setReadTimeout(10000);
connection.connect();

InputStream stream = connection.getInputStream();

SAXParserFactory spf = SAXParserFactory.newInstance();
SAXParser sp = spf.newSAXParser();

XMLReader xr = sp.getXMLReader();

xr.parse(new InputSource(stream));  // The line that throws the exception

Why would the Activity force-close and then run without any problems immediately after? Would a BufferedInputStream be any different? I’m baffled. 🙁

Thanks for your time everyone.

Update: It turns out HttpURLConnection.getResponseCode() returns -1 every so often, so the InputStream probably isn’t being correctly set.

Answer 1

HTTPURLConnection connection = (HttpURLConnection) serverAddress.openConnection();
connection.setRequestMethod("GET");
connection.setDoOutput(true);

Those lines are a bit odd. Is it HTTPURLConnection or HttpURLConnection? The default request method is already GET. The setDoOutput(true) will however force it to POST.

I’d replace all of those lines by

URLConnection connection = serverAddress.openConnection();

and retry. It might happen that it returned an error because you forced POST and didn’t write anything to the output (the request body). The connection.connect() is by the way already implicitly called by connection.getInputStream(), so that line is superfluous as well.

Update: does the following for testing purposes work?

BufferedReader reader = new BufferedReader(new InputStreamReader(stream, "UTF-8"));
for (String line; (line = reader.readLine()) != null;) {
    System.out.println(line);
}
reader.close();