Re: [7.0.0-SNAPSHOT] HTML HEAD is... emptied !

[Andrea Del Bene]

Hi Sebastien,

this is caused by the changes I did lately to improve component queuing 
features. We are working on it and I'm opening an issue to better work 
on this feature.

BTW, with the very last snapshot this error should have gone. Can you 
give it a try?
Hi devs,

I've got a new one today...

Just having an AjaxButton, and press F5 (or Ctrl+F5)... As the result the
HTML header is completely emptied!

This was not producing in -M3. In addition, when I click "back" in my app,
I get this error:

java.lang.NullPointerException
      at 
org.apache.wicket.ajax.AbstractAjaxResponse$AjaxHtmlHeaderContainer.newHeaderResponse(AbstractAjaxResponse.java:521)
      at 
org.apache.wicket.markup.html.internal.HtmlHeaderContainer.getHeaderResponse(HtmlHeaderContainer.java:350)
      at 
org.apache.wicket.markup.html.internal.HtmlHeaderContainer.onComponentTagBody(HtmlHeaderContainer.java:163)
      at 
org.apache.wicket.markup.html.panel.DefaultMarkupSourcingStrategy.onComponentTagBody(DefaultMarkupSourcingStrategy.java:70)
      at 
org.apache.wicket.Component.internalRenderComponent(Component.java:2557)
      at org.apache.wicket.MarkupContainer.onRender(MarkupContainer.java:1553)
      at org.apache.wicket.Component.internalRender(Component.java:2372)
      at org.apache.wicket.Component.render(Component.java:2300)
      at org.apache.wicket.MarkupContainer.renderNext(MarkupContainer.java:1421)
      at org.apache.wicket.MarkupContainer.renderAll(MarkupContainer.java:1614)
      at org.apache.wicket.Page.onRender(Page.java:879)
      at org.apache.wicket.markup.html.WebPage.onRender(WebPage.java:142)
      at org.apache.wicket.Component.internalRender(Component.java:2372)
      at org.apache.wicket.Component.render(Component.java:2300)
      at org.apache.wicket.Page.renderPage(Page.java:1018)
      at 
org.apache.wicket.request.handler.render.WebPageRenderer.renderPage(WebPageRenderer.java:124)
      at 
org.apache.wicket.request.handler.render.WebPageRenderer.respond(WebPageRenderer.java:195)
      at 
org.apache.wicket.core.request.handler.RenderPageRequestHandler.respond(RenderPageRequestHandler.java:175)
      at 
org.apache.wicket.request.cycle.RequestCycle$HandlerExecutor.respond(RequestCycle.java:837)
      at 
org.apache.wicket.request.RequestHandlerStack.execute(RequestHandlerStack.java:64)
      at 
org.apache.wicket.request.cycle.RequestCycle.execute(RequestCycle.java:265)
      at 
org.apache.wicket.request.cycle.RequestCycle.processRequest(RequestCycle.java:222)
      at 
org.apache.wicket.request.cycle.RequestCycle.processRequestAndDetach(RequestCycle.java:293)
      at 
org.apache.wicket.protocol.ws.AbstractUpgradeFilter.processRequestCycle(AbstractUpgradeFilter.java:59)
      at 
org.apache.wicket.protocol.http.WicketFilter.processRequest(WicketFilter.java:203)
      at 
org.apache.wicket.protocol.http.WicketFilter.doFilter(WicketFilter.java:284)

Complete stack:

org.apache.wicket.WicketRuntimeException: Exception in rendering
component: [AjaxHtmlHeaderContainer [Component id = _header_]]
      at 
org.apache.wicket.Component.internalRenderComponent(Component.java:2581)
      at org.apache.wicket.MarkupContainer.onRender(MarkupContainer.java:1553)
      at org.apache.wicket.Component.internalRender(Component.java:2372)
      at org.apache.wicket.Component.render(Component.java:2300)
      at org.apache.wicket.MarkupContainer.renderNext(MarkupContainer.java:1421)
      at org.apache.wicket.MarkupContainer.renderAll(MarkupContainer.java:1614)
      at org.apache.wicket.Page.onRender(Page.java:879)
      at org.apache.wicket.markup.html.WebPage.onRender(WebPage.java:142)
      at org.apache.wicket.Component.internalRender(Component.java:2372)
      at org.apache.wicket.Component.render(Component.java:2300)
      at org.apache.wicket.Page.renderPage(Page.java:1018)
      at 
org.apache.wicket.request.handler.render.WebPageRenderer.renderPage(WebPageRenderer.java:124)
      at 
org.apache.wicket.request.handler.render.WebPageRenderer.respond(WebPageRenderer.java:195)
      at 
org.apache.wicket.core.request.handler.RenderPageRequestHandler.respond(RenderPageRequestHandler.java:175)
      at 
org.apache.wicket.request.cycle.RequestCycle$HandlerExecutor.respond(RequestCycle.java:837)
      at 
org.apache.wicket.request.RequestHandlerStack.execute(RequestHandlerStack.java:64)
      at 
org.apache.wicket.request.cycle.RequestCycle.execute(RequestCycle.java:265)
      at 
org.apache.wicket.request.cycle.RequestCycle.processRequest(RequestCycle.java:222)
      at 
org.apache.wicket.request.cycle.RequestCycle.processRequestAndDetach(RequestCycle.java:293)
      at 
org.apache.wicket.protocol.ws.AbstractUpgradeFilter.processRequestCycle(AbstractUpgradeFilter.java:59)
      at 
org.apache.wicket.protocol.http.WicketFilter.processRequest(WicketFilter.java:203)



The quickstart is ready but it's actually very simple to reproduce:

         final FeedbackPanel feedback = new FeedbackPanel("feedback");
         this.add(feedback.setOutputMarkupId(true));

         final Form<?> form = new Form<Void>("form");
         this.add(form);

         form.add(new TextField<String>("myinput", Model.of("")));
         form.add(new AjaxButton("mybutton") {

             private static final long serialVersionUID = 1L;

             @Override
             protected void onSubmit(AjaxRequestTarget target, Form<?> form)
             {
                 super.onSubmit(target, form);

                 this.info("ok, now click F5");
                 target.add(feedback);
             }
         });


Thanks,
Sebastien