使用TreeNode时发生的错误

[MacJoin]

部分代码如下：
//得到系统树
public JScrollPane getTree(){
// FileSystem fs=new FileSystem().open();
File[] root=FileSystemView.getFileSystemView().getRoots(); //获得系统文件的根节点
// File[] root=File.listRoots();
MyNode filenod=new MyNode(root[0]);
filenod.explore();
jtree=new AgileSuperJTreeBasic();
jtree.getSelectionModel().setSelectionMode(TreeSelectionModel.SINGLE_TREE_SELECTION);//选择任何项
jtree1=new JScrollPane(jtree);
jtree1.setBorder(BorderFactory.createEtchedBorder(Color.white, new Color(148,145,140)));
jtree.setShowsRootHandles(true);
jtree.addTreeExpansionListener(new TreeExpansionListener(){

@Override
public void treeCollapsed(TreeExpansionEvent event) {
// TODO Auto-generated method stub

}

@Override
public void treeExpanded(TreeExpansionEvent e) {
// TODO Auto-generated method stub
TreePath treePath=e.getPath();
MyNode node=(MyNode) treePath.getLastPathComponent();
[b]if(!node.isExplored()){
DefaultTreeModel model=((DefaultTreeModel)jtree.getModel());
node.explore();
model.nodeStructureChanged(node);
}
}

});
return jtree1;
}

报的错误如下：


Exception in thread "AWT-EventQueue-0" java.lang.ClassCastException: com.databaseHelp.AgileSuperJTreeBasic$FileNode cannot be cast to com.logic.MyNode[/b]