docs: @Override
  	public long getCount(long fromWhen, long toWhen,  boolean fromInclusive, boolean toInclusive){
  		NavigableMap<Long, AtomicLong> range = ((NavigableMap<Long, AtomicLong>)counters.getMap()).subMap(fromWhen, fromInclusive, toWhen, toInclusive);
  		long count = 0;
  		for(AtomicLong c: range.values()){
  			count += c.longValue();
  		}
  		return count;
  	}