Como selecionar o Diretório da Jtree?

Assuntos Gerais
#1

Eu quero que minha JTree navegue pela pasta raiz ( C:\ ), como faço isso!?

Esta é a classe que estou trabalhando:

package Frames;

import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.List;

import javax.swing.GroupLayout;
import javax.swing.JComponent;
import javax.swing.JFileChooser;
import javax.swing.JFrame;
import javax.swing.JList;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JOptionPane;
import javax.swing.JScrollPane;
import javax.swing.JSeparator;
import javax.swing.JTree;
import javax.swing.LayoutStyle;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.tree.TreePath;

import java.io.File;

import sun.management.FileSystem;
import sun.security.x509.Extension;

import com.swtdesigner.SwingResourceManager;

public class FramePrincipal extends JFrame {

private JTree tree;
private JList list;
String x = "C:";
public FramePrincipal() {
	super();
	setIconImage(SwingResourceManager.getImage(FramePrincipal.class, "/com/sun/java/swing/plaf/windows/icons/Computer.gif"));
	setTitle("Controle de curriculo - CATHO");
	setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

	JScrollPane scrollPane;
	scrollPane = new JScrollPane();

	list = new JList();
	scrollPane.setViewportView(list);

	JScrollPane scrollPane_1;
	scrollPane_1 = new JScrollPane();

	tree = new JTree();


	scrollPane_1.setViewportView(tree);
	final GroupLayout groupLayout = new GroupLayout((JComponent) getContentPane());
	groupLayout.setHorizontalGroup(
		groupLayout.createParallelGroup(GroupLayout.Alignment.LEADING)
			.addGroup(groupLayout.createSequentialGroup()
				.addContainerGap()
				.addComponent(scrollPane, GroupLayout.PREFERRED_SIZE, 249, GroupLayout.PREFERRED_SIZE)
				.addGap(12, 12, 12)
				.addComponent(scrollPane_1, GroupLayout.DEFAULT_SIZE, 274, Short.MAX_VALUE)
				.addContainerGap())
	);
	groupLayout.setVerticalGroup(
		groupLayout.createParallelGroup(GroupLayout.Alignment.LEADING)
			.addGroup(groupLayout.createSequentialGroup()
				.addContainerGap()
				.addGroup(groupLayout.createParallelGroup(GroupLayout.Alignment.LEADING)
					.addComponent(scrollPane_1, GroupLayout.PREFERRED_SIZE, 205, GroupLayout.PREFERRED_SIZE)
					.addComponent(scrollPane, GroupLayout.PREFERRED_SIZE, 300, GroupLayout.PREFERRED_SIZE))
				.addContainerGap(39, Short.MAX_VALUE))
	);
	getContentPane().setLayout(groupLayout);

	final JMenuBar menuBar = new JMenuBar();
	setJMenuBar(menuBar);

	final JMenu arquivoMenu = new JMenu();
	arquivoMenu.setText("Arquivo");
	menuBar.add(arquivoMenu);

	final JMenuItem newItemMenuItem = new JMenuItem();
	newItemMenuItem.addActionListener(new ActionListener() {
		public void actionPerformed(final ActionEvent arg0) {
			dispose();
		}
	});
	newItemMenuItem.setText("Sair");
	arquivoMenu.add(newItemMenuItem);
	pack();
	//
}

}

Agradeço desde já!

#2