openbravo widget - How do I know the widget_instance_id from the jsp or html?

Question

I am creating a custom URLwidget for openbravo and I need to know the widget instance ID from the jsp or servlet level. Here is what I have:

  public class MyCutomWidget extends HttpSecureAppServlet {

  private static final long serialVersionUID = 1L;

  public void doGet(HttpServletRequest request, HttpServletResponse response)
      throws ServletException, IOException {
  }

  protected void doPost(HttpServletRequest request, HttpServletResponse response)
      throws ServletException, IOException {
  }

And I created a jsp for this widget and pointed to it when I created the widget itself from openbravo (logged in as a system admin). I also have a DAO that updates the widget instance table.

All I need is a way to know the current widget instance ID from the jsp or servlet. Any clue?