public Object step(int step) throws Cancel { helper.assertStep(step); contexts = manager.getSessionData(); if (contexts.isEmpty()) { return Collections.emptyList(); } final ServiceFactory sf = helper.getServiceFactory(); final List<ome.model.meta.Session> sessions = new ArrayList<>(contexts.size()); for (final String uuid : contexts.keySet()) { final Long sessionId = provider.findSessionIdByUuid(uuid, sf); if (sessionId != null) { final ome.model.meta.Session session = provider.findSessionById(sessionId, sf); if (session != null) { sessions.add(session); } } } return sessions; }