How to load data

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// -------- Fragment ----------

public class ImagesFragment extends Fragment implements LoaderCallbacks<List<String>> {

        @Override
	public void onActivityCreated(Bundle savedInstanceState) {
		super.onActivityCreated(savedInstanceState);
		
		// create and auto start loader
		getLoaderManager().initLoader(0, null, this);
	}

	@Override
	public Loader<List<Image>> onCreateLoader(int id, Bundle args) {
		// create own loader, for memory safety do not pass Activity reference
		return new UrlLoader(getActivity().getApplicationContext());
	}

        @Override
	public void onLoadFinished(Loader<List<String>> arg0, List<String> arg1) {
		// update UI based on result of urls: arg1
	}

	@Override
	public void onLoaderReset(Loader<List<String>> arg0) {
		// clear UI
	}
}

// ---------- Loader --------------

public final class UrlLoader extends AsyncTaskLoader<List<String>> {

	private List<String> urls;

	public ImagesLoader(Context context) {
		super(context);
	}

	@Override
	protected void onStartLoading() {
		// just make sure if we already have content to deliver
		if (urls != null)
			deliverResult(urls);

		// otherwise if something has been changed or first try
		if (takeContentChanged() || urls == null)
			forceLoad();
	}

	@Override
	protected void onStopLoading() {
		cancelLoad();
	}

	@Override
	protected void onReset() {
		super.onReset();

		onStopLoading();

		// clear reference to object
		// it's necessary to allow GC to collect the object
		// to avoid memory leaking
		urls = null;
	}

	private static String streamToString(InputStream stream) {
		Writer writer = new StringWriter();
		InputStreamReader input = new InputStreamReader(new BufferedInputStream(stream), "UTF-8");
		
		try {
			final char[] buffer = new char[1024];
			int read;

			while ((read = input.read(buffer)) != -1)
				writer.write(buffer, 0, read);
		} finally {
			input.close();
		}
		
		return writer.toString();
	}

	@Override
	public List<String> loadInBackground() {
                // even if fail return empty list and print exception stack trace
		List<String> result = new ArrayList<String>();
		
		// Do not use HttpClient, see http://android-developers.blogspot.com/2011/09/androids-http-clients.html
		try {
			HttpURLConnection httpURLConnection = (HttpURLConnection) new URL("http://my.super.website.com/get/json/response").openConnection();
			// by default it's a GET request
			try {
				InputStream input = new BufferedInputStream(httpURLConnection.getInputStream());
				String jsonResponse = streamToString(input);
				
				// parse somehow...
				result.add("http://my.super.website.com/some/url/to/image");
				result.add("http://my.super.website.com/some/url/to/something/else");
			} finally {
				httpURLConnection.disconnect();
			}
		} catch (MalformedURLException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		}
		
		return Collections.unmodifiableList(result);
    }
}