JTree 编辑、删除、添加节点

import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTree;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.tree.DefaultTreeModel;
import javax.swing.tree.TreeNode;
import javax.swing.tree.TreePath;

public class EditJTree  
{  
    JFrame jf;  
 
    JTree tree;  
    //上面JTree对象对应的model  
    DefaultTreeModel model;  
      
    //定义几个初始节点  
    DefaultMutableTreeNode root = new DefaultMutableTreeNode("中国");   
    DefaultMutableTreeNode guangdong = new DefaultMutableTreeNode("广东");  
    DefaultMutableTreeNode guangxi = new DefaultMutableTreeNode("广西");  
    DefaultMutableTreeNode foshan = new DefaultMutableTreeNode("佛山");  
    DefaultMutableTreeNode shantou = new DefaultMutableTreeNode("汕头");  
    DefaultMutableTreeNode guilin = new DefaultMutableTreeNode("桂林");  
    DefaultMutableTreeNode nanning = new DefaultMutableTreeNode("南宁");  
 
    //定义需要被拖动的TreePath  
    TreePath movePath;  
 
    JButton addSiblingButton = new JButton("添加兄弟节点");  
    JButton addChildButton = new JButton("添加子节点");  
    JButton deleteButton = new JButton("删除节点");  
    JButton editButton = new JButton("编辑当前节点");  
 
    public void init()  
    {  
        guangdong.add(foshan);  
        guangdong.add(shantou);  
        guangxi.add(guilin);  
        guangxi.add(nanning);  
        root.add(guangdong);  
        root.add(guangxi);  
          
        jf = new JFrame("树");  
        tree = new JTree(root);  
        //获取JTree对应的TreeModel对象  
        model = (DefaultTreeModel)tree.getModel();  
        //设置JTree可编辑  
        tree.setEditable(true);  
        MouseListener ml = new MouseAdapter()   
        {  
            //按下鼠标时候获得被拖动的节点  
            public void mousePressed(MouseEvent e)  
            {  
                //如果需要唯一确定某个节点，必须通过TreePath来获取。  
                TreePath tp = tree.getPathForLocation(e.getX(), e.getY());  
                if (tp != null)  
                {  
                    movePath = tp;  
                }  
            }  
            //鼠标松开时获得需要拖到哪个父节点  
            public void mouseReleased(MouseEvent e)  
            {  
                //根据鼠标松开时的TreePath来获取TreePath  
                TreePath tp = tree.getPathForLocation(e.getX(), e.getY());  
 
                if (tp != null && movePath != null)  
                {  
                    //阻止向子节点拖动  
                    if (movePath.isDescendant(tp) && movePath != tp)  
                    {  
                        JOptionPane.showMessageDialog(jf, "目标节点是被移动节点的子节点，无法移动！",   
                            "非法操作", JOptionPane.ERROR_MESSAGE );  
                        return;  
                    }  
                    //既不是向子节点移动，而且鼠标按下、松开的不是同一个节点  
                    else if (movePath != tp)  
                    {  
                        System.out.println(tp.getLastPathComponent());  
                        //add方法可以先将原节点从原父节点删除，再添加到新父节点中  
                        ((DefaultMutableTreeNode)tp.getLastPathComponent()).add(  
                            (DefaultMutableTreeNode)movePath.getLastPathComponent());  
                        movePath = null;  
                        tree.updateUI();  
                    }  
                }  
            }  
        };  
        tree.addMouseListener(ml);  
 
        JPanel panel = new JPanel();  
 
        addSiblingButton.addActionListener(new ActionListener()  
        {  
            public void actionPerformed(ActionEvent event)  
            {  
                //获取选中节点  
                DefaultMutableTreeNode selectedNode  
                    = (DefaultMutableTreeNode) tree.getLastSelectedPathComponent();  
                //如果节点为空，直接返回  
                if (selectedNode == null) return;  
                //获取该选中节点的父节点  
                DefaultMutableTreeNode parent  
                    = (DefaultMutableTreeNode)selectedNode.getParent();  
                //如果父节点为空，直接返回  
                if (parent == null) return;  
                //创建一个新节点  
                DefaultMutableTreeNode newNode = new DefaultMutableTreeNode("新节点");  
                //获取选中节点的选中索引  
                int selectedIndex = parent.getIndex(selectedNode);  
                //在选中位置插入新节点  
                model.insertNodeInto(newNode, parent, selectedIndex + 1);  
                //--------下面代码实现显示新节点（自动展开父节点）-------  
                //获取从根节点到新节点的所有节点  
                TreeNode[] nodes = model.getPathToRoot(newNode);  
                //使用指定的节点数组来创建TreePath  
                TreePath path = new TreePath(nodes);  
                //显示指定TreePath  
                tree.scrollPathToVisible(path);  
            }  
        });  
        panel.add(addSiblingButton);  
 
        addChildButton.addActionListener(new ActionListener()  
        {  
            public void actionPerformed(ActionEvent event)  
            {  
                //获取选中节点  
                DefaultMutableTreeNode selectedNode  
                    = (DefaultMutableTreeNode) tree.getLastSelectedPathComponent();  
                //如果节点为空，直接返回  
                if (selectedNode == null) return;  
                //创建一个新节点  
                DefaultMutableTreeNode newNode = new DefaultMutableTreeNode("新节点");  
                //直接通过model来添加新节点，则无需通过调用JTree的updateUI方法  
                //model.insertNodeInto(newNode, selectedNode, selectedNode.getChildCount());  
                //直接通过节点添加新节点，则需要调用tree的updateUI方法  
                selectedNode.add(newNode);  
                //--------下面代码实现显示新节点（自动展开父节点）-------  
                TreeNode[] nodes = model.getPathToRoot(newNode);  
                TreePath path = new TreePath(nodes);  
                tree.scrollPathToVisible(path);  
                tree.updateUI();  
            }  
        });  
        panel.add(addChildButton);  
 
        deleteButton.addActionListener(new ActionListener()  
        {  
            public void actionPerformed(ActionEvent event)  
            {  
                DefaultMutableTreeNode selectedNode  
                    = (DefaultMutableTreeNode) tree.getLastSelectedPathComponent();  
                if (selectedNode != null && selectedNode.getParent() != null)  
                {  
                    //删除指定节点  
                    model.removeNodeFromParent(selectedNode);  
                }  
            }  
        });  
        panel.add(deleteButton);  
 
        editButton.addActionListener(new ActionListener()  
        {  
            public void actionPerformed(ActionEvent event)  
            {  
                TreePath selectedPath = tree.getSelectionPath();  
                if (selectedPath != null)  
                {  
                    //编辑选中节点  
                    tree.startEditingAtPath(selectedPath);  
                }  
            }  
        });  
        panel.add(editButton);  
 
        jf.add(new JScrollPane(tree));  
        jf.add(panel , BorderLayout.SOUTH);  
        jf.pack();  
        jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);  
        jf.setVisible(true);  
    }  
 
    public static void main(String[] args)   
    {  
        new EditJTree().init();  
    }  
}