本题中定义了一个树型的通信录，窗口左侧是一个树，右侧是一个文本域，单击树的结点，则在右侧文本域中显示相关信息，如果单击的是树结点，则显示对应名字的电话信息。
import javax.swing.*;
import javax.swing.tree.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.event.*;
class Mytree2 extends JFrame
JTree tree=null;JTextArea text=new JTextArea(20,20);
Mytree2()
Container con=getContentPane();
DefaultMutableTreeNode root=new DefauhMutableTreeNode("同学通信录");
DefaultMutableTreeNode t1=new DefauhMutableTreeNode("大学同学");
DefaultMutableTreeNode t2=new DefaultMutableTreeNode("研究生同学");
DefaultMutableTreeNode t1_1=new DefauhMutableTreeNode("陈艳");
DefaultMutableTreeNode t1_2=new DefauhMutableTreeNode("李小永");
DefaultMutableTreeNode t2_1=new DefauhMutableTreeNode("王小小");
DefaultMutableTreeNode t2_2=new DefauhMutableTreeNode("董小");
setTitle("java2");
root.add(t1);root.add(t2);
t1.add(t1_1);t1.add(t1_2);t2.add(t2_1);t2.add(t2_2);
tree=new ITree(root);
JScrollPane scrollpane=new JScrollPane(text);
JSplitPane splitpane=new JSplitPane(JSplitPane.HORIZONTAL_SPLIT,
true,tree,scrollpane);
tree.addTreeSelectionListener(this);
con.add(splitpane);
addWindowListener(Flew WindowAdapter()
public void windowClosing(WindowEvent e)
System.ext(0);)));
setVisible(true);setBounds(70,80,200,300);
public void valueChanged(TreeSelectionEvent e)
if(e.getSource()==tree)
DefaultMutableTreeNode node=
(DefauhMutableTreeNode)tree.getLastSelectedPathComponent();
if(node.isLeaf())
String str=______;
if(str.equals("陈艳"))
text.setText(str+"：联系电话：0411-4209876");
else if(str.equals("李小永"))
text.setText(str+"：联系电话：010-62789876");
else if(str.equals("王小小"))
text.setText(str+"：联系电话：0430-63596677");
else if(str.equals("董小"))
text.setText(str+"：联系电话：020-85192789");)
else
text.setText(node.getUserObject().toString());
public class java2
public static void main(String args[])
Mytree2 win=new Mytree2();win.pack();