public static synchronized OWLOntologyDocumentSource getOntologyInputSource(URI uri) throws ODPRegistryCacheException,
URIUnresolvableException {
if (getUnresolvedURIs().contains(uri)) throw new URIUnresolvableException();
if (uris.containsKey(uri)) {
File f = uris.get(uri);
FileDocumentSource fds = new FileDocumentSource(f);
return fds;
} else {
try {
retrieveRemoteResource(uri);
return getOntologyInputSource(uri);