private FileLock getFileLockWithinOffset(String path, long from, long to) {
		LinkedList<FileLock> list = this.getFileLockList(path, false);
		if (list == null)
			return null;
		for (FileLock lock : list)
		{
			if ((from >= lock.from && from <= lock.to) || 
				(to >= lock.from && to <= lock.to) ||
				(from <= lock.from && to >= lock.to))
				return lock;
		}
		return null;
	}