Heads down :-) Together with Pedro we made another brainstorm session in IRC and we realised how 1.4 works. I'll write it down here for the generations. If Matej still reads here I'd love to hear his confirmation.
In short: there is no need to change anything! In details: Wicket stores the page instances in the session in org.apache.wicket.page.PersistentPageManager.SessionEntry object. When the http session has to be replicated or there are more pages in the memory than the configured (see org.apache.wicket.pageStore.DefaultPageStore.SerializedPagesCache.size) then those pages has to be serialized. Case 1) Here if there is Application available (worker thread) then a SerializedPage is created from a Page instance. A SerializedPage is as I said earlier: int pageId; String sessionId; byte[] data; // the page itself pageId and sessionId are used to be able to be able to find later the page in the IDataStore (e.g. DiskDataStore) and cleaned if the session expires from this store. Case 2) There is no Application (WicketFilter#destroy() thread) then the http session is being serialized by the web container so that after restart of the application/container the application can reload its sessions. In this case we don't need the session id for our needs in IDataStore (because it is not used in this case) and we can serialize just the Page instance without the two additional slots. Later when org.apache.wicket.page.PersistentPageManager.SessionEntry.readObject(ObjectInputStream) is called we load just Serializable in an List (org.apache.wicket.page.PersistentPageManager.SessionEntry.afterReadObject). This Serializable can be either Page or SerializedPage. Even later when the first org.apache.wicket.page.PersistentPageManager.SessionEntry.getPage(int) comes (this is always a worker thread, so there is Application available) the entries from this List are passed to org.apache.wicket.pageStore.IPageStore.convertToPage(Object) where they are potentially converted from SerializedPage to Page. That's it. This is how it works in 1.4 too. Just in 1.5 the related classes are either renamed or completely rewritten. The fix is removal of two lines. I tested it with Tomcat7 and wicket-examples -> compref -> TabbedPanel. Scenario: - start the app. - click randomly on the tabs. - stop the app - start the app - click on any tab Without the fix I get PageExpiredException at the last step and the reported exception in the ticket when stopping the app With the fix there are no exceptions at all and clicking on any tab works just like there was no restart. On Fri, Mar 18, 2011 at 7:19 PM, Igor Vaynberg <igor.vaynb...@gmail.com>wrote: > even if it were a singleton, some containers will load spooled > sessions on startup before the filter is initialized, thus even the > singleton would be not yet there. > > -igor > > On Fri, Mar 18, 2011 at 11:17 AM, Pedro Santos <pedros...@gmail.com> > wrote: > > PersistentPageManager$SessionEntry is the serializable piece of Wicket > > inside the servlet session, IMO it should serialize/deserialize > regardless > > of the Wicket lifecycle. Can the DefaultPageStore be changed to be a > > singleton an not a per application instance? > > > > On Fri, Mar 18, 2011 at 12:42 PM, Igor Vaynberg <igor.vaynb...@gmail.com > >wrote: > > > >> i would say that the lack of response shows that people dont care > >> about a couple more xml lines they have to add to web.xml once and > >> forget about. > >> > >> -igor > >> > >> On Fri, Mar 18, 2011 at 7:47 AM, Martin Grigorov <mgrigo...@apache.org> > >> wrote: > >> > On Thu, Mar 17, 2011 at 10:54 PM, Martin Grigorov < > mgrigo...@apache.org > >> >wrote: > >> > > >> >> Hi, > >> >> > >> >> To solve https://issues.apache.org/jira/browse/WICKET-3470 we need > to > >> >> introduce ServletContextListener in Wicket. > >> >> In comment > >> >> > >> > https://issues.apache.org/jira/browse/WICKET-3470?focusedCommentId=13008166&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-13008166Idescribeda > proposal how we can change web.xml configuration to make it > >> >> working. The proposal is based on a discussion between me and Igor in > >> IRC. > >> >> > >> >> This is a rather big change and we need more opinions, so please > share > >> if > >> >> you have ideas. > >> >> > >> > > >> > By "big" here I mean conceptually, not code wise. Technically it > doesn't > >> > seem to be big or complex. > >> > > >> >> > >> >> --martin-g > >> >> > >> >> P.S. I'm interested to understand why there is no such problem with > >> Wicket > >> >> 1.4? > >> >> I guess sessions in 1.4 are cleared earlier and never persisted > between > >> web > >> >> container restarts. > >> >> > >> >> -- > >> >> Martin Grigorov > >> >> jWeekend > >> >> Training, Consulting, Development > >> >> http://jWeekend.com <http://jweekend.com/> > >> >> > >> >> > >> > > >> > > >> > -- > >> > Martin Grigorov > >> > jWeekend > >> > Training, Consulting, Development > >> > http://jWeekend.com <http://jweekend.com/> > >> > > >> > > > > > > > > -- > > Pedro Henrique Oliveira dos Santos > > > -- Martin Grigorov jWeekend Training, Consulting, Development http://jWeekend.com <http://jweekend.com/>
