if (map == null) {
return new LongArrayEmptyClosableIterator();
} else {
Iterator<Map.Entry<Long, ClosableMap<Long, ClosableMap<Long, Set<Long>>>>> entryIterator =
map.entrySet().iterator();
return new FlatteningFourLongClosableIterator(new ClosableIteratorImpl<Map.Entry<Long,
ClosableMap<Long, ClosableMap<Long, Set<Long>>>>>(entryIterator));
}
}