private void addEmptyThings(){
		SortedSet<String> keys = new TreeSet<String>(data.keySet());
		for (String path : keys) {
			while(true){
				path = deleteLastLevel(path);
				if(path == null || path.equals("")) {
					break;
				}
				if(data.get(path) == null){
					data.put(path, " ");
				}
			}
		}
	}