// Calculate feed hashes basing on their present XML URLs for later updates upon successful completion
Map<DirectFeed, Integer> feedHashes = calculateFeedHashes(guidesSet);
OPMLGuideSet opmlSet = Converter.convertToOPML(guidesSet, "BlogBridge Feeds");
Document doc = new Exporter(true).export(opmlSet);
// prepare parameters for server call
String opml = Transformation.documentToString(doc);
int userId = ServerService.syncStore(aEmail, aPassword, opml);