private Document<Service> service_doc;
private Document<Feed> feed_doc;
private Document<Service> init_service_doc(Abdera abdera) {
Factory factory = abdera.getFactory();
Service service = factory.newService();
Workspace workspace = service.addWorkspace("Simple");
try {
Collection collection = workspace.addCollection("Simple", "atom/feed");
collection.setAccept("entry");
collection.addCategories().setFixed(false);