import javax.swing.*;

import javax.swing.event.*;

import javax.swing.tree.*;

import java.io.File;



public class FileTreeDemo {



    /**

     * @param args

     */

    public static void main(String[] args) {

        // TODO Auto-generated method stub

        File root;

        if (args.length>0)

            root = new File(args[0]);

        else

            root = new File(System.getProperty("user.home"));

        

        FileTreeModel model =new FileTreeModel(root);

        

        JTree tree=new JTree();

        tree.setModel(model);

        JScrollPane scrollpane =new JScrollPane(tree);

        JFrame frame =new JFrame("FileTreeDemo");

        frame.getContentPane().add(scrollpane,"Center");

        frame.setSize(400,600);

        frame.setVisible(true);

        

        



    }



}

class FileTreeModel implements TreeModel{

    protected File root;

    public FileTreeModel(File root)

    {

        this.root=root;

    }

    public Object getRoot(){

        return root;

    }

    public boolean isLeaf(Object node){

        return ((File)node).isFile();

    }

    public int getChildCount(Object parent){

        String [] children=((File)parent).list();

        if (children==null) return 0;

        return children.length;

    }

    

    public Object getChild(Object parent ,int index){

        String[] children=((File)parent).list();

        if((children==null)||(index>=children.length))return null;

        return new File((File)parent ,children[index]);

    }

    public int getIndexOfChild(Object parent,Object child){

        String[] children =((File)parent).list();

        if (children ==null)return -1;

        String childname=((File)child).getName();

        for (int i=0;i<children.length;i++)

            if(childname.equals(children[i])) return i;

        return -1;

    }

    

    public void valueForPathChanged(TreePath path,Object newvalue){}

    public void addTreeModelListener(TreeModelListener l){}

    public void removeTreeModelListener(TreeModelListener l){}

    

}