Swing/TreeNodePopupMenu のバックアップ(No.1)

static class TreePopupMenu extends JPopupMenu {
  private TreePath[] tsp;
  public TreePopupMenu() {
    super();
    add(new AbstractAction("path") {
      public void actionPerformed(ActionEvent e) {
        JOptionPane.showMessageDialog(null, tsp, "path",
          JOptionPane.INFORMATION_MESSAGE);
      }
    });
    add(new JMenuItem("dummy"));
  }
  public void show(Component c, int x, int y) {
    JTree tree = (JTree)c;
    tsp = tree.getSelectionPaths();
    if(tsp!=null) {
      TreePath path = tree.getPathForLocation(x, y);
      if(path!=null && Arrays.asList(tsp).contains(path)) {
        super.show(c, x, y);
      }
    }
  }
}