code:         public void onStartup(Set<Class<?>> c, ServletContext ctx)
                  throws ServletException {
              Servlet s;
              
              if (createServlet) {
                  s = ctx.createServlet(servlet.getClass());
              } else {
                  s = servlet;
              }
              ServletRegistration.Dynamic r = ctx.addServlet("servlet", s);
              r.addMapping("/");
          }
      }
  }
  