### Question:
NotificationData { public RemoveNotificationResult removeNotificationForMessage(MessageReference messageReference) { NotificationHolder holder = getNotificationHolderForMessage(messageReference); if (holder == null) { return RemoveNotificationResult.unknownNotification(); } activeNotifications.remove(holder); int notificationId = holder.notificationId; markNotificationIdAsFree(notificationId); if (!additionalNotifications.isEmpty()) { NotificationContent newContent = additionalNotifications.removeFirst(); NotificationHolder replacement = createNotificationHolder(notificationId, newContent); activeNotifications.addLast(replacement); return RemoveNotificationResult.createNotification(replacement); } return RemoveNotificationResult.cancelNotification(notificationId); } NotificationData(Account account); AddNotificationResult addNotificationContent(NotificationContent content); boolean containsStarredMessages(); boolean hasSummaryOverflowMessages(); int getSummaryOverflowMessagesCount(); int getNewMessagesCount(); boolean isSingleMessageNotification(); NotificationHolder getHolderForLatestNotification(); List<NotificationContent> getContentForSummaryNotification(); int[] getActiveNotificationIds(); RemoveNotificationResult removeNotificationForMessage(MessageReference messageReference); Account getAccount(); int getUnreadMessageCount(); void setUnreadMessageCount(int unreadMessageCount); ArrayList<MessageReference> getAllMessageReferences();  }### Answer:
@Test public void testRemoveNotificationForMessage() throws Exception { NotificationContent content = createNotificationContent("1"); notificationData.addNotificationContent(content); RemoveNotificationResult result = notificationData.removeNotificationForMessage(content.messageReference); assertFalse(result.isUnknownNotification()); assertEquals(NotificationIds.getNewMailStackedNotificationId(account, 0), result.getNotificationId()); assertFalse(result.shouldCreateNotification()); }