/**
* @return Returns null if uri could not be loaded
*/
private Stylesheet parse(StylesheetInfo info) {
CSSResource cr = _userAgentCallback.getCSSResource(info.getUri());
if (cr==null) return null;
// Whether by accident or design, InputStream will never be null
// since the null resource stream is wrapped in a BufferedInputStream
InputSource inputSource=cr.getResourceInputSource();
if (inputSource==null) return null;
InputStream is = inputSource.getByteStream();
if (is==null) return null;
try {
return parse(new InputStreamReader(is, "UTF-8"), info);