JTree 遍历叶节点解决方法

JTree 遍历叶节点
我用JTree做了一个QQ好友列表。当服务器发送一个在线好友的ID过来，如"100 500 200"，ID之间用空格分隔。我要如何遍历JTree，找到该叶节点，并设置setEnable(true)。求帮忙解决。字数有限，贴出关键代码：
public class QQClientMain extends JFrame {

  //登入者id
  private String owner;

  // 是否有消息
  private static boolean hasMessage;
   
 // 初始化中部(好友列表和群列表的显示)
  public void initCenter() {
  // 初始化好友列表
  DefaultMutableTreeNode root = new DefaultMutableTreeNode(new TreeNode("0","好友列表"));
  // 一级节点
  DefaultMutableTreeNode node1 = new DefaultMutableTreeNode(new TreeNode("1","我的好友"));
  DefaultMutableTreeNode node2 = new DefaultMutableTreeNode(new TreeNode("2","陌生人"));
  DefaultMutableTreeNode node3 = new DefaultMutableTreeNode(new TreeNode("3","黑名单"));
   
  // 子节点
  // 好友
  DefaultMutableTreeNode node1_1 = new DefaultMutableTreeNode(new TreeNode("100","张三","image/1-1.gif", "0"));
  DefaultMutableTreeNode node1_2 = new DefaultMutableTreeNode(new TreeNode("200","李四","image/2-1.gif", "0"));
  DefaultMutableTreeNode node1_3 = new DefaultMutableTreeNode(new TreeNode("300","王五","image/3-1.gif", "0"));
  DefaultMutableTreeNode node1_4 = new DefaultMutableTreeNode(new TreeNode("400","李流","image/4-1.gif", "0"));
  DefaultMutableTreeNode node1_5 = new DefaultMutableTreeNode(new TreeNode("500","黄山","image/5-1.gif", "0"));
  DefaultMutableTreeNode node1_6 = new DefaultMutableTreeNode(new TreeNode("600","武当","image/6-1.gif", "0"));
  // 陌生人
  DefaultMutableTreeNode node2_1 = new DefaultMutableTreeNode(new TreeNode("1300","张三1","image/4-1.gif", "0"));
  // 黑名单
  DefaultMutableTreeNode node3_1 = new DefaultMutableTreeNode(new TreeNode("1010","张三1","image/2-1.gif", "0"));
   
  jpt1_tree1 = new JTree(root);
  jpt1_tree1.setCellRenderer(new MyCellRenderer());
  jpt1_jsp1 = new JScrollPane(jpt1_tree1);
  // 设置单击展开树节点
  jpt1_tree1.setToggleClickCount(1);
   
  root.add(node1);
  root.add(node2);
  root.add(node3);
   
  node1.add(node1_1);
  node1.add(node1_2);
  node1.add(node1_3);
  node1.add(node1_4);
  node1.add(node1_5);
  node1.add(node1_6);



  node2.add(node2_1);
   
  node3.add(node3_1);

  //设置是否显示根节点的“展开/折叠”图标,默认是false  
  jpt1_tree1.setShowsRootHandles(false);  
  //设置节点是否可见,默认是true  
  jpt1_tree1.setRootVisible(false);
  jpt1_tree1.setEditable(false);
   
  //设置使用Windows风格外观  
  try {
  UIManager.setLookAndFeel("com.sun.java.swing.plaf.windows.WindowsLookAndFeel");
  } catch (ClassNotFoundException e1) {
  e1.printStackTrace();
  } catch (InstantiationException e1) {
  e1.printStackTrace();
  } catch (IllegalAccessException e1) {
  e1.printStackTrace();
  } catch (UnsupportedLookAndFeelException e1) {
  e1.printStackTrace();
  }  
  //更新JTree的UI外观  
  SwingUtilities.updateComponentTreeUI(jpt1_tree1);  

   
  // 创建选项卡窗口
  jtp1 = new JTabbedPane(JTabbedPane.TOP);
  // 选项卡一:好友列表

   
  jtp1_jpl1 = new JPanel(new BorderLayout());
  jtp1_jpl1.add(jpt1_jsp1, "Center");
   
  jtp1_jpl2 = new JPanel();
  jpt1_jpl3 = new JPanel();
   
  jtp1.add(jtp1_jpl1, "联系人");
  jtp1.add(jtp1_jpl2, "群");
  jtp1.add(jpt1_jpl3, "最近联系人");
   
  jtp1.setBounds(10, 160, 235, 280);
  this.add(jtp1);
   
   
  // 为好友列表树添加响应事件
  jpt1_tree1.addMouseListener(new MouseAdapter() {
   

// // 返回当前选择的第一个节点中的最后一个路径组件
// DefaultMutableTreeNode dmtnTemp = (DefaultMutableTreeNode) jpt1_tree1.getLastSelectedPathComponent();
   
  @Override
  public void mouseClicked(MouseEvent e) {
  JTree tree = (JTree) e.getSource();
  int selRow = tree.getRowForLocation(e.getX(), e.getY());
  TreePath selPath = tree.getPathForLocation(e.getX(), e.getY());
   
  if(selRow != -1) {
  DefaultMutableTreeNode node = (DefaultMutableTreeNode) selPath.getLastPathComponent();
   
  if(node != null) {
  // 返回此节点的用户对象
  TreeNode treeNode = (TreeNode) node.getUserObject();
   
  // 如果是叶子节点
  if(node.isLeaf()) {
  // 如果是双击
  if(e.getClickCount() == 2) {
  // 获得要聊天的好友id
  String friendId = treeNode.getId();  
  QQChat qqChat = new QQChat(owner, friendId);
  //把聊天界面加入管理聊天窗口的类中
  ManageQQChat.addQQChat(owner + " " + friendId, qqChat);
  }
  }
  }
  }
  }

  @Override
  public void mouseEntered(MouseEvent e) {
   
  }

  @Override
  public void mouseExited(MouseEvent arg0) {
  // TODO Auto-generated method stub
  super.mouseExited(arg0);
  }
   
  });
   
 }
   
 class MyCellRenderer extends DefaultTreeCellRenderer {
  @Override
  public Component getTreeCellRendererComponent(JTree tree, Object value,
  boolean selected, boolean expanded, boolean leaf, int row,
  boolean hasFocus) {
   
   
  // 获得节点对象
  DefaultMutableTreeNode node = (DefaultMutableTreeNode)value;  
  TreeNode treeNode = (TreeNode) node.getUserObject();
  String id = treeNode.getId();
  String nickname = treeNode.getValue();
  String image = treeNode.getImage();

   
   
  // 设置叶节点的图标
  if(leaf && image != null) {
  setLeafIcon(new ImageIcon(image));
  }
  // 设置展开的节点的图标
  if(expanded) {
  setOpenIcon(new ImageIcon("image/openFloder.jpg"));
  }
  // 设置关闭的节点的图标
  else {
  setClosedIcon(new ImageIcon("image/closeFloder.jpg"));
  }
   
  // 执行父类默认的节点绘制操作
  super.getTreeCellRendererComponent(tree, value, selected, expanded, leaf, row, hasFocus);
   
  // 设置节点显示内容
  this.setText(nickname);
  // 节点状态
  String statue = treeNode.getStatue();
  // 设置节点灰色
  if(leaf && statue != null) {
  this.setEnabled(false);
  // 在线状态显示高亮
  if(treeNode.getStatue().equals(QQStatue.qq_online)) {
  this.setEnabled(true);
  }
  // 本人显示高亮
  if(treeNode.getId().equals(owner)) {

  this.setEnabled(true);
  }
  }
   
  return this;
  }
  }
  
 public static void main(String[] args) {
  new QQClientMain("600");
  }
  

}
========================================

public class TreeNode {
  
 // 节点编号
  String id;
  // 节点值
  String value;
  // 节点图片
  String image;
  // 节点状态
  String statue;
  //............
  }

(运行效果请见http://photo.blog.sina.com.cn/photo/8bcfeedagc855de609d6b)

[解决办法]
jTree.addTreeSelectionListener(new javax.swing.event.TreeSelectionListener() {
public void valueChanged(javax.swing.event.TreeSelectionEvent evt) {
DefaultMutableTreeNode node = (DefaultMutableTreeNode) jTree.getLastSelectedPathComponent();
String name=node.toString();

if(node.isLeaf()){
if(name.equals("100")){
setEnable(true)； }
}）；
[解决办法]
一般来说遍历树结构建议用递归，也就是从根节点开始，进行递归搜索叶子节点。

大致如下：

Java code

    // 主入口函数    public void setOnline(DefaultMutableTreeNode root, String friends) {        String[] fs = friends.split("\\s");        HashSet<String> set = new HashSet<String>(Arrays.asList(fs)); // 转成Set便于快速检索        setOnlineRecursion(root, set); // 调用递归子函数        xxoo.UpdateUI(); // 刷新下树显示    }    // 递归函数    private void setOnlineRecursion(DefaultMutableTreeNode node, Set onlines) {        Enumeration<DefaultMutableTreeNode> children = node.children();        while (children.hasMoreElements()) {            DefaultMutableTreeNode child = children.nextElement();            if (child.isLeaf()) { // 是否叶子节点                TreeNode treeNode = (TreeNode) node.getUserObject();                if (onlines.contains(treeNode.getId())) { // 检查该ID是否在set中                    treeNode.setStatus(QQStatue.在线);                } else {                    treeNode.setStatus(QQStatue.离线);                }            } else {                 // 非叶子节点则继续递归调用了                setOnlineRecursion(child, onlines);            }        }    }