### Question:
CallTree { public void notifySequential(SubsystemContext<?> context, String notificationKey, int delayMs) { notifySequential(context, notificationKey, null, delayMs); } CallTree(String callTreeContextAttr); void notifySequential(SubsystemContext<?> context, String notificationKey, int delayMs); void notifySequential(SubsystemContext<?> context, String notificationKey, Map<String, String> params, int delayMs); void notifyParallel(SubsystemContext<?> context, String notificationKey, Map<String, String> alertParams); void onScheduledEvent(ScheduledEvent event, SubsystemContext<?> context); void cancel(SubsystemContext<?> context); boolean hasNext(SubsystemContext<?> context); void syncCallTree(SubsystemContext<? extends SubsystemModel> context); static LinkedHashMap<String, Boolean> callTreeToMap(List<Map<String, Object>> callTree); static List<Map<String, Object>> callTreeToList(Map<String, Boolean> callTree); static final String CALL_TREE_INDEX_KEY; static final String CALL_TREE_TIMEOUT_KEY; static final String NOTIFICATION_PARAMETERS_KEY; }### Answer:
@Test public void testCallTreeEmpty() { SecuritySubsystemModel.setCallTree(model, ImmutableList.<Map<String,Object>>of()); callTree.notifySequential(context, SECURITY_ALERT_KEY, SEQ_TIMEOUT); Assert.assertEquals("should have sent 0 messages",0, messgaesSent.getValues().size()); }