@Override
	public void set(String path, Object value){
		if(value == null && cache.containsKey(path)){
			cache.remove(path);
			modified = true;
		}else if(value != null){
			if(!value.equals(get(path))){
				modified = true;
			}
			cache.put(path, value);

		}
		super.set(path, value);
	}