关于JTREE的问题~~~~~~~~~

Question

在删除树的节点的时候老是出问题!!!!!!!!!
代码如下:
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.tree.*;
import javax.swing.event.*;
class JTreeTest extends JFrame
{
Container cn;


JPopupMenu jpm=new JPopupMenu();

JPopupMenu jpm1=new JPopupMenu();

JMenu jm=new JMenu("编辑");
JMenuItem jmi1=new JMenuItem("编辑");
JMenuItem jmi2=new JMenuItem("删除");
JMenuItem jmi3=new JMenuItem("退出");


 
JMenuItem jmi4=new JMenuItem("锁定");
JMenuItem jmi5=new JMenuItem("解锁");




DefaultMutableTreeNode root=new DefaultMutableTreeNode("JTree");

DefaultMutableTreeNode colors=new DefaultMutableTreeNode("colors");

DefaultMutableTreeNode sports=new DefaultMutableTreeNode("sports");

DefaultMutableTreeNode basketball=new DefaultMutableTreeNode("basketball");
DefaultMutableTreeNode football=new DefaultMutableTreeNode("football");
DefaultMutableTreeNode hockey=new DefaultMutableTreeNode("hockey");

DefaultMutableTreeNode food=new DefaultMutableTreeNode("food");

DefaultMutableTreeNode hotdog=new DefaultMutableTreeNode("hotdog");
DefaultMutableTreeNode pizza=new DefaultMutableTreeNode("pizza");
DefaultMutableTreeNode ravioli=new DefaultMutableTreeNode("ravioli");
DefaultMutableTreeNode banana=new DefaultMutableTreeNode("banana");

JTree tree;

JButton btn1=new JButton("删除");
JButton btn2=new JButton("退出");

DefaultMutableTreeNode node;
JTreeTest()
{
cn=this.getContentPane();
cn.setLayout(null);
tree=new JTree(root);
tree.setBounds(50,20,240,280);
btn2.setBounds(180,320,80,30);
btn1.setBounds(80,320,80,30);


root.add(colors);

root.add(sports);
sports.add(basketball);
sports.add(football);
sports.add(hockey);

root.add(food);
food.add(hotdog);
food.add(pizza);
food.add(ravioli);
food.add(banana);

cn.add(tree);
cn.add(btn1);
cn.add(btn2);

jpm.add(jm);
jpm.add(jmi2);
jpm.add(jmi3);


jm.add(jmi4);
jm.add(jmi5);
cn.addMouseListener(new MouseAdapter()
{
public void mouseClicked(MouseEvent e)
{
cn.add(jpm);
jpm.show(cn,e.getX(),e.getY());
}
}
);
jmi3.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
System.exit(0);
}
}
);
jmi4.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
tree.setEnabled(false);
}
});
jmi5.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
tree.setEnabled(true);
}
});


tree.addTreeSelectionListener(new TreeSelectionListener()
{
public void valueChanged(TreeSelectionEvent e)
{
node=(DefaultMutableTreeNode)tree.getLastSelectedPathComponent();
System.out.println(node);
}
});

--------------------------------------btn1.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{

try
{
node.remove(node);
JOptionPane.showMessageDialog(cn,"已成功删除节点","删除",JOptionPane.QUESTION_MESSAGE);
}
catch(Exception e1)
{
e1.printStackTrace();
}
System.out.println("when delete node="+node);
}
});

btn2.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
System.exit(0);
}
});



this.setSize(new Dimension(500,400));
this.setTitle("节点选择");
this.setVisible(true);
}
public static void main(String []args)
{
JTreeTest obj=new JTreeTest();
}

}
关键的地方加了条线!!!!!!!!!!!!
难道是我的方法有问题吗?
每次在删除的时候都有一个异常-----argument is not a child
望高手解答!!!!!!!!!!!
在线等~~~~~~~~~~~

Answer 1

node.remove(node);
哪能自己把自己给删除了,先去找到它的父节点,再
DefaultMutableTreeNode parentNode=(DefaultMutableTreeNode)node.getParent();
parentNode.remove(node);
DefaultTreeModel treeModel = (DefaultTreeModel) tree.getModel();
treeModel.reload(parentNode);
tree.repaint();

Answer 2

DefaultTreeModel treeModel = (DefaultTreeModel) tree.getModel();
treeModel.reload(parentNode);带来的异常!!!!!!!!!!!!