Tapestry hook: start of rendering and end of rendering

I am trying to use jamon to collect statistics (time to render a web page) of a website using tapestry.

How can I proceed to have

• a method executed when the request is received by the server, i.e. the start of the rendering ?
• a method executed when th开发者_运维百科e response is all sent, i.e. the end of the rendering ?

I am trying to use the @OnEvent annotation but I'm not going very far with that.

You could create a RequestFilter to wrap the actual rendering between calls to your own code:

public class RenderStatisticsFilter implements RequestFilter {

   @Override
   public boolean service(Request request, Response response,
            RequestHandler handler) throws IOException {
       this.beforeRender();         
       final boolean result = handler.service(request, response);
       this.afterRender();
       return result;
   }

   private void beforeRender() {
       ...
   }

   private void afterRender() {
       ...
   }    

}

You'd need to contribute your filter to the rendering pipeline via your application module:

public void contributeRequestHandler(
        final OrderedConfiguration<RequestFilter> configuration) {
    configuration.add("RenderStatisticsFilter", new RenderStatisticsFilter());
}

Tapestry has extensible pipelines that organize the logic for any particular type of request. I'm not sure if you are trying to measure over-all request processing time, or just the time spent rendering (and, in Tapestry, there's actually rendering the DOM, and then streaming the DOM to the client). The HttpServletRequestHandler pipeline is a good place to put a filter that can measure over all response time for all requests (but does not provide a good way to select only page render requests), the PageRenderRequestHandler pipeline is good for measuring time to render and stream the page.