public FileSystem(String dirName) throws Exception {
	Loader L = new Loader();
	try {
	    root = new Tree<FileNode>(new FileNode("CWD",true));
	    HashMap<String,File> hm = L.load(dirName);
	    for (String k : hm.keySet()) {
		String[] path = k.split("[\\/]");
		if(false) System.out.println("path: "+k);
		QueueList<String> q = new QueueList<String>();
		for (String p : path) { q.enqueue(p.equals("")?"CWD":p); }
		q.dequeue();
		insertPath(root,q);
	    }
	} catch (Exception e) {
	    System.out.println("Error loading directory "+dirName);
	    throw e;
	}
    }