/* * This code is based on an example provided by Richard Stanford,  * a tutorial reader. */import java.awt.*;import java.awt.event.*;import javax.swing.*;import javax.swing.tree.*;public class DynamicTreeDemo extends JPanel {    private int newNodeSuffix = 1;    public DynamicTreeDemo(JFrame frame) {        //create the components        final DynamicTree treePanel = new DynamicTree();        populateTree(treePanel);        JButton addButton = new JButton("Add");        addButton.addActionListener(new ActionListener() {            public void actionPerformed(ActionEvent e) {                treePanel.addObject("New Node " + newNodeSuffix++);            }        });        JButton removeButton = new JButton("Remove");        removeButton.addActionListener(new ActionListener() {            public void actionPerformed(ActionEvent e) {                treePanel.removeCurrentNode();            }        });        JButton clearButton = new JButton("Clear");        clearButton.addActionListener(new ActionListener() {            public void actionPerformed(ActionEvent e) {                treePanel.clear();            }        });        //Lay everything out.        setLayout(new BorderLayout());        treePanel.setPreferredSize(new Dimension(300, 150));        add(treePanel, BorderLayout.CENTER);        JPanel panel = new JPanel();        panel.setLayout(new GridLayout(0,1));        panel.add(addButton);        panel.add(removeButton);        panel.add(clearButton);        add(panel, BorderLayout.EAST);    }    public void populateTree(DynamicTree treePanel) {        String p1Name = new String("Parent 1");        String p2Name = new String("Parent 2");        String c1Name = new String("Child 1");        String c2Name = new String("Child 2");        DefaultMutableTreeNode p1, p2;        p1 = treePanel.addObject(null, p1Name);        p2 = treePanel.addObject(null, p2Name);        treePanel.addObject(p1, c1Name);        treePanel.addObject(p1, c2Name);        treePanel.addObject(p2, c1Name);        treePanel.addObject(p2, c2Name);    }    public static void main(String[] args) {        JFrame frame = new JFrame("DynamicTreeDemo");        Container contentPane = frame.getContentPane();        contentPane.setLayout(new GridLayout(1,1));        contentPane.add(new DynamicTreeDemo(frame));        frame.addWindowListener(new WindowAdapter() {            public void windowClosing(WindowEvent e) {                System.exit(0);            }        });        frame.pack();        frame.setVisible(true);    }}