code: public static void postAction (Component source, String command)
      {
          // slip things onto the event queue for later
          ActionEvent event = new ActionEvent(source, 0, command);
          EventQueue.invokeLater(new ActionInvoker(event));
      }
docs: Like {@link #postAction(ActionEvent)} except that it constructs the
  action event for you with the supplied source component and string
  command. The <code>id</code> of the event will always be set to
  zero.