the problem has been solved
import javax.swing.*;
import javax.swing.tree.*;
import java.awt.event.*;
import java.awt.*;
import java.util.*;
import java.io.*;
public class SimpleTree extends JFrame
{
private JTree tree;
private JTextArea text;
private DefaultTreeModel treeModel;
private DefaultMutableTreeNode rootNode;
private TreePath tp;
private File file;
public SimpleTree()
{
setLayout(new BorderLayout());
addWindowListener(new WindowAdapter()
{
public void windowClosing(WindowEvent we)
{
writeObjectTreeModel();
System.exit(0);
}
});
readObjectTreeModel();
tree = new JTree(treeModel);
tree.setRootVisible(false);
add(new JScrollPane((JTree)tree),"Center");
text = new JTextArea(80,80);
add(text,"East");
tree.addMouseListener(new MouseAdapter()
{
public void mouseClicked(MouseEvent me)
{
tp = tree.getSelectionPath();
MutableTreeNode selectNode = (MutableTreeNode) tp.getLastPathComponent();
String file = selectNode.toString();
if (tp != null)
{
String file1 = file.replaceAll("\\\\", "\\\\\\\\");
System.out.println(file1);
try
{
BufferedReader in = new BufferedReader(new FileReader(file1));
String str;
while ((str = in.readLine()) != null)
text.append(str);
in.close();
}
catch (IOException e)
{
}
}
}
});
setSize(800,800);
setVisible(true);
}
public void getList(DefaultMutableTreeNode node, File f)
{
if(!f.isDirectory())
{
DefaultMutableTreeNode folder = new DefaultMutableTreeNode(f);
node.add(folder);
}
else if(f.isDirectory())
{
DefaultMutableTreeNode child = new DefaultMutableTreeNode(f);
node.add(child);
File fList[] = f.listFiles();
for (int i = 0; i < fList.length; i++)
getList(child, fList[i]);
}
}
public void writeObjectTreeModel()
{
try
{
ObjectOutputStream oos = new ObjectOutputStream(new FileOutputStream("treeModel.dat"));
oos.writeObject(treeModel);
oos.close();
}
catch (Exception e)
{
e.printStackTrace();
}
}
public void readObjectTreeModel()
{
try
{
ObjectInputStream ois = new ObjectInputStream(new FileInputStream("treeModel.dat"));
treeModel = (DefaultTreeModel)ois.readObject();
rootNode = (DefaultMutableTreeNode)treeModel.getRoot();
String str = JOptionPane.showInputDialog(tree,"Enter New Project");
getList(rootNode, new File(str));
ois.close();
}
catch (Exception e)
{
e.printStackTrace();
rootNode = new DefaultMutableTreeNode("Sports");
treeModel = new DefaultTreeModel(rootNode);
}
}
public static void main(String s[])
{
try
{
UIManager.setLookAndFeel("com.sun.java." + "swing.plaf.motif.MotifLookAndFeel");
}
catch (Exception e)
{
e.printStackTrace();
}
SimpleTree frame = new SimpleTree();
}
}
ty for the help again david