Code example for TreeSet

Methods: isEmptyfirst

     * Checks to see if there are any unread messages or delivery 
     * reports.  Shows the most recent notification if there is one. 
     * @param context the context to use 
     * @param isNew if notify a new message comes, it should be true, otherwise, false. 
	public static void blockingUpdateNewMessageIndicator(Context context, boolean isNew) {
        SortedSet<WapPushNotificationInfo> accumulator =
                new TreeSet<WapPushNotificationInfo>(INFO_COMPARATOR);
        Set<Long> threads = new HashSet<Long>(4);
        int count = 0;
        count += accumulateNotificationInfo(
                accumulator, getWapPushNewMessageNotificationInfo(context, threads));
        cancelNotification(context, NOTIFICATION_ID);
        if (!accumulator.isEmpty()) {
            accumulator.first().deliver(context, isNew, count, threads.size());