public boolean addValue(LabItem lab)
	{
		if(lab == null)
		{
			return false;
		}
		else if(containsValue(lab))
		{
			return false;
		}
		Iterator<LectureItem> it = workingItems.keySet().iterator();
		LectureItem current;
		while(it.hasNext())
		{
			current = it.next();
			if(matchs(current, lab))
			{
				workingItems.put(current, lab);
				return true;
			}
		}
		return false;
	}