jTree序列化的奇怪问题。。。

Question

hehe !
这个问题我以前也碰到过！
后来，我查看代码是我的选择侦听事件注册器，注册了两次！
呵呵！
看看能给你什么启发吗？
呵呵1

Answer 1

void jMenuFileOpen_actionPerformed(ActionEvent e) {
    boolean  bResult=true;
    String filename=null;
    File file=null;    fc.setFileFilter(new ExampleFileFilter("cn","Concept Network files"));
    fc.setAcceptAllFileFilterUsed(false);
    int returnVal = fc.showOpenDialog(this);
    if (returnVal == JFileChooser.APPROVE_OPTION) {
      file=fc.getSelectedFile();
      filename = file.getPath();
    }else{
      //the user push the Cancel button
    }
    //the following code is just for test
    ObjectInputStream in1=null;    File f=new File(filename);
    try{
        in1 = new ObjectInputStream(new FileInputStream(f));
        jTree1=(JTree)in1.readObject();
    }catch(IOException e1){
        JOptionPane.showMessageDialog(null,"failed to read file!","Error",0);
    }catch(ClassNotFoundException e2){
        JOptionPane.showMessageDialog(null,"cannot find the class file"+filename+"!","Error",0);
    }
    jTree1.setModel(treeModel);
    treeModel.addTreeModelListener(new MyTreeModelListener());
    //Listen for when the selection changes.
    jTree1.addTreeSelectionListener(new TreeSelectionListener() {
        public void valueChanged(TreeSelectionEvent e) {
          jTree1_valueChanged(e);
        }
    });
    MouseListener popupListener = new PopupListener();
    jTree1.addMouseListener(popupListener);//han    scrollPane=new JScrollPane(jTree1);
    jSplitPane1.setLeftComponent(scrollPane);
    jSplitPane1.setDividerLocation(200);
    jSplitPane1.validate();
  }
初始化的时候也有一段代码：
//Create the nodes.
    root=new DefaultMutableTreeNode(new Concept("root","ROOT"));
    treeModel=new DefaultTreeModel(root);
    treeModel.addTreeModelListener(new MyTreeModelListener());
    jTree1= new JTree(root);
    createNodes(root);
    jTree1.setAutoscrolls(true);
    jTree1.setBorder(BorderFactory.createEtchedBorder());
    jTree1.setEditable(false);
    jTree1.setModel(treeModel);
    jTree1.setRootVisible(false);
    jTree1.setShowsRootHandles(true);
    scrollPane = new JScrollPane(jTree1);
    //Create a tree that allows one selection at a time.
    jTree1.getSelectionModel().setSelectionMode
            (TreeSelectionModel.SINGLE_TREE_SELECTION);
    //Listen for when the selection changes.
    jTree1.addTreeSelectionListener(new TreeSelectionListener() {
        public void valueChanged(TreeSelectionEvent e) {
          jTree1_valueChanged(e);
        }
    });
    //Add listener to components that can bring up popup menus.
    MouseListener popupListener = new PopupListener();
    jTree1.addMouseListener(popupListener);//han