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();
}
}