Swing/DirectoryTree のバックアップ(No.4)

class FolderSelectionListener implements TreeSelectionListener{
  private final FileSystemView fileSystemView;
  public FolderSelectionListener(FileSystemView fileSystemView) {
    this.fileSystemView = fileSystemView;
  }
  @Override public void valueChanged(TreeSelectionEvent e) {
    final JTree tree = (JTree)e.getSource();
    final DefaultMutableTreeNode node =
      (DefaultMutableTreeNode)e.getPath().getLastPathComponent();
    final DefaultTreeModel model = (DefaultTreeModel)tree.getModel();
    //final TreePath path = e.getPath();

    if(!node.isLeaf()) return;
    final File parent = (File)node.getUserObject();
    if(!parent.isDirectory()) return;

    SwingWorker<String, File> worker = new SwingWorker<String, File>() {
      @Override public String doInBackground() {
        File[] children = fileSystemView.getFiles(parent, true);
        for(File child: children) {
          if(child.isDirectory()) {
            publish(child);
          }
        }
        return "done";
      }
      @Override protected void process(java.util.List<File> chunks) {
        for(File file: chunks) {
          node.add(new DefaultMutableTreeNode(file));
        }
        model.nodeStructureChanged(node);
        //tree.expandPath(path);
      }
    };
    worker.execute();
  }
}