HttpClient response handler always returns closed stream
- by Alex Ciminian
I'm new to Java development so please bear with me. Also, I hope I'm not the champion of tl;dr :).
I'm using HttpClient to make requests over Http (duh!) and I'd gotten it to work for a simple servlet that receives an URL as a query string parameter. I realized that my code could use some refactoring, so I decided to make my own HttpResponseHandler, to clean up the code, make it reusable and improve exception handling.
I currently have something like this:
public class HttpResponseHandler implements ResponseHandler<InputStream>{
public InputStream handleResponse(HttpResponse response)
throws ClientProtocolException, IOException {
int statusCode = response.getStatusLine().getStatusCode();
InputStream in = null;
if (statusCode != HttpStatus.SC_OK) {
throw new HttpResponseException(statusCode, null);
} else {
HttpEntity entity = response.getEntity();
if (entity != null) {
in = entity.getContent();
// This works
// for (int i;(i = in.read()) >= 0;) System.out.print((char)i);
}
}
return in;
}
}
And in the method where I make the actual request:
HttpClient httpclient = new DefaultHttpClient();
HttpGet httpget = new HttpGet(target);
ResponseHandler<InputStream> httpResponseHandler = new HttpResponseHandler();
try {
InputStream in = httpclient.execute(httpget, httpResponseHandler);
// This doesn't work
// for (int i;(i = in.read()) >= 0;) System.out.print((char)i);
return in;
} catch (HttpResponseException e) {
throw new HttpResponseException(e.getStatusCode(), null);
}
The problem is that the input stream returned from the handler is closed. I don't have any idea why, but I've checked it with the prints in my code (and no, I haven't used them both at the same time :). While the first print works, the other one gives a closed stream error.
I need InputStreams, because all my other methods expect an InputStream and not a String. Also, I want to be able to retrieve images (or maybe other types of files), not just text files.
I can work around this pretty easily by giving up on the response handler (I have a working implementation that doesn't use it), but I'm pretty curious about the following:
Why does it do what it does?
How do I open the stream, if something closes it?
What's the right way to do this, anyway :)?
I've checked the docs and I couldn't find anything useful regarding this issue. To save you a bit of Googling, here's the Javadoc and here's the HttpClient tutorial (Section 1.1.8 - Response handlers).
Thanks,
Alex
