String resourceFile = (String) jarFileResources.get(systemID);
if (resourceFile != null) {
// retrieve a URL to the resource in the jar.
URL url = getResourceURL(resourceFile);
if (url == null) {
throw new ExtendedSAXException("Could not resolve the entity " +
systemID);
} else {
// create the InputSource
inputSource = new InputSource(url.toExternalForm());
}