JTreeのノード追加、削除

class TreePopupMenu extends JPopupMenu {
  private TreePath path;
  public TreePopupMenu() {
    super();
    add(new AbstractAction("add") {
      @Override public void actionPerformed(ActionEvent e) {
        JTree tree = (JTree) getInvoker();
        DefaultTreeModel model = (DefaultTreeModel) tree.getModel();
        DefaultMutableTreeNode parent =
          (DefaultMutableTreeNode) path.getLastPathComponent();
        DefaultMutableTreeNode child  = new DefaultMutableTreeNode("New");
        model.insertNodeInto(child, parent, parent.getChildCount());
        // parent.add(child);
        // model.reload(); // = model.nodeStructureChanged(parent);
        tree.expandPath(path);
      }
    });
    add(new AbstractAction("remove") {
      @Override public void actionPerformed(ActionEvent e) {
        JTree tree = (JTree) getInvoker();
        DefaultTreeModel model = (DefaultTreeModel) tree.getModel();
        DefaultMutableTreeNode node =
          (DefaultMutableTreeNode) path.getLastPathComponent();
        // if (path.getParentPath() != null) {
        if (!node.isRoot()) {
          model.removeNodeFromParent(node);
        }
      }
    });
  }

  @Override public void show(Component c, int x, int y) {
    JTree tree = (JTree) c;
    TreePath[] tsp = tree.getSelectionPaths();
    path = tree.getPathForLocation(x, y);
    if (path != null && Arrays.asList(tsp).contains(path)) {
      super.show(c, x, y);
    }
  }
}