Do you see java.io.ObjectOutputStream#writeObject0() in the stack ? Each occurrence of this method gives you information about the currently being written object. The next occurrence of this method in the stack tells you which Java object is the owner of the previous one. I don't have time now to make a screencast :-/
Martin Grigorov Wicket Training and Consulting https://twitter.com/mtgrigorov On Fri, Jun 17, 2016 at 12:37 PM, Dieter Tremel <tre...@tremel-computer.de> wrote: > Hello Martin, > > I tried this to learn it, but didn't find it. > > I put a breakpoint at org.apache.wicket.serialize.java.JavaSerializer > SerializationCheckerObjectOutputStream#writeObjectOverride line 260 and > 277 and looked at the variables content. > > The obj was the complete page PersonenTable and I had to look at all the > children in the page hierarchy. Not straight forward to find. > > Did I miss something? > > Thanks Dieter > > Am 17.06.2016 um 11:56 schrieb Martin Grigorov: > > Hi Dieter, > > > > It is quite easy to debug such issues by putting a breakpoint at line > where > > the exception is being thrown. > > Once you have the debugger stopped there you could click on the stack > > methods to see what was the parent object of the currently failing one. > > > > Martin Grigorov > > Wicket Training and Consulting > > https://twitter.com/mtgrigorov > > > > On Fri, Jun 17, 2016 at 11:46 AM, Dieter Tremel < > tre...@tremel-computer.de> > > wrote: > > > >> Hello Bas, > >> > >> first of all let me thank you and Martin for your great support and the > >> helpful thoughts and examples :-) > >> > >> I am using wicket 7.30, the use of onBefore() is an old pattern I have > >> been used to, changed it now to > >> @Override > >> protected void onInitialize() { > >> super.onInitialize(); > >> initMarkup(); > >> } > >> on all pages. > >> > >> The last days I spent a lot of time in analyzing, debugging, some > >> refactoring, searching. But I didn't find the culprit yet. :-( > >> > >> Your example is useful, I read some similar blogpost about outside final > >> vars in methods of anonymous inner classes, but had no match in my code > >> so far. > >> > >> I will do some more exhaustive search and report, if I solved the > problem. > >> > >> Thank You > >> Dieter > >> > >> Am 16.06.2016 um 16:32 schrieb Bas Gooren: > >>> Hi Dieter, > >>> > >>> > >>> Which version of wicket are you using? (I ask since I see you are using > >>> onBeforeRender() to initialize your components, while since wicket 1.5 > >>> there is onInitialize() for that in each component). > >>> > >>> > >>> For as far as I can see there are no references to your dao in the gist > >>> you provided; However, since it is serialized somewhere in the > component > >>> tree, it could be in one of the smaller components used in your > >>> PersonenTable page. > >>> > >>> In any case, your page (or a component inside it) has a reference to > >>> your dao. > >>> > >>> > >>> Since I’ve seen this a lot when I started using wicket, please check if > >>> you are referencing your dao somewhere inside an anonymous inner class > / > >>> component. > >>> > >>> > >>> E.g.: > >>> > >>> > >>> public Component createMyComponent(String id) { > >>> > >>> DAO dao = getDaoFromPageOrElsewhere(); > >>> > >>> return new AjaxLink<Void>(id) { > >>> > >>> public void onClick(AjaxRequestTarget target) { > >>> > >>> // This is where an instance of DAO will get serialized into the > >>> component tree! > >>> > >>> dao.performAction(); > >>> > >>> } > >>> > >>> } > >>> > >>> } > >>> > >>> > >>> Rewrite such code (if you have it) to look up the DAO reference at the > >>> time you actually need it: > >>> > >>> > >>> public void onClick(AjaxRequestTarget target) { > >>> > >>> DAO dao = getDaoFromPageOrElsewhere(); > >>> > >>> dao.performAction(); > >>> > >>> } > >>> > >>> > >>> My guess is that you’ll find the culprit by simply looking at all > places > >>> in your code where you use the PersonenDao. > >>> > >>> > >>> Met vriendelijke groet, > >>> Kind regards, > >>> > >>> Bas Gooren > >>> > >>> Op 15 juni 2016 bij 16:25:25, Dieter Tremel (tre...@tremel-computer.de > >>> <mailto:tre...@tremel-computer.de>) schreef: > >>> > >>>> Hello Martin, > >>>> > >>>> it is: > >>>> > >>>> personenProvider = (com.sun.proxy.$Proxy24) > >>>> org.apache.wicket.proxy.LazyInitProxyFactory$JdkHandler@6eb3b9ea > >>>> > >>>> wrapInProxies is true > >>>> > >>>> I added a SignIn mechanism, SignInSession uses PersonenDao too to > >>>> authorize in the database. But I checked not to have any references to > >>>> it, that could be serialized. I added more of this this part to the > >> gist: > >>>> > >>>> https://gist.github.com/tremel/dd9bfa252282b5853d6d464feccaad29 > >>>> > >>>> Dieter > >>>> > >>>> Am 15.06.2016 um 15:00 schrieb Martin Grigorov: > >>>>> Hi, > >>>>> > >>>>> Put a breakpoint at PersonenTable constructor and see what is the > >> type of ' > >>>>> personenProvider'. > >>>>> It must be JDK Proxy instance. > >>>>> If it is not then something wrong is going on. > >>>>> > >>>>> > >> > org.apache.wicket.guice.GuiceComponentInjector#GuiceComponentInjector(org.apache.wicket.Application, > >>>>> com.google.inject.Injector, boolean) - the last parameter here is > >>>>> 'wrapInProxies'. It must be 'true'. > >>>>> > >>>>> Martin Grigorov > >>>>> Wicket Training and Consulting > >>>>> https://twitter.com/mtgrigorov > >>>>> > >>>>> On Wed, Jun 15, 2016 at 2:18 PM, Dieter Tremel < > >> tre...@tremel-computer.de <mailto:tre...@tremel-computer.de>> > >>>>> wrote: > >>>>> > >>>>>> Hi Bas, > >>>>>> > >>>>>> I put it in http://pastie.org/private/19zeomb8uy1beb1gfjegq > >>>>>> > >>>>>> I fear it is not really useful, since it starts with > >>>>>> > >>>>>> org.apache.wicket.WicketRuntimeException: A problem occurred while > >>>>>> trying to collect debug information about not serializable object > >>>>>> > >>>>>> Dieter > >>>>>> > >>>>>> Am 15.06.2016 um 13:39 schrieb Bas Gooren: > >>>>>>> Hi Dieter, > >>>>>>> > >>>>>>> Can you share the stack trace of the serialization checker error? > >>>>>>> Normally it points out where in the hierarchy it found a > >>>>>>> non-serializable object. > >>>>>>> My first guess is that you are referencing the dao class somewhere > >>>>>>> directly from your page. The stack trace will prove me right or > >> wrong :-) > >>>>>>> > >>>>>>> Met vriendelijke groet, > >>>>>>> Kind regards, > >>>>>>> > >>>>>>> Bas Gooren > >>>>>>> > >>>>>>> Op 15 juni 2016 bij 13:29:24, Dieter Tremel ( > >> tre...@tremel-computer.de <mailto:tre...@tremel-computer.de> > >>>>>>> <mailto:tre...@tremel-computer.de <mailto: > tre...@tremel-computer.de>>) > >> schreef: > >>>>>>> > >>>>>>>> Hello Bas, > >>>>>>>> > >>>>>>>> I try to cut small pieces of the code, please tell me if you want > >> to see > >>>>>>>> more. > >>>>>>>> > >>>>>>>> First the error: > >>>>>>>> > >>>>>>>> 12:59:03.919 [http-nio-8084-exec-6] WARN > >>>>>>>> o.a.w.c.u.o.c.CheckingObjectOutputStream - error delegating to > >>>>>>>> writeObject : > >>>>>>>> > >>>>>> > >> > de.tremel_computer.abi81.datahandling.PersonenDao$$EnhancerByGuice$$4769627f, > >>>>>>>> > >>>>>>>> path: /children > >>>>>>>> 12:59:03.925 [http-nio-8084-exec-6] ERROR > >>>>>>>> o.a.w.serialize.java.JavaSerializer - Error serializing object > >> class > >>>>>>>> de.tremel_computer.abi81.pages.PersonenTable [object=[Page class = > >>>>>>>> de.tremel_computer.abi81.pages.PersonenTable, id = 1, render count > >> = 1]] > >>>>>>>> org.apache.wicket.WicketRuntimeException: A problem occurred while > >>>>>>>> trying to collect debug information about not serializable object > >>>>>>>> at > >>>>>>>> > >>>>>> > >> > org.apache.wicket.serialize.java.JavaSerializer$SerializationCheckerObjectOutputStream.writeObjectOverride(JavaSerializer.java:278) > >>>>>>>> > >>>>>>>> > >>>>>>>> > >>>>>>>> > >>>>>>>> public class PersonenTable extends BasePage { > >>>>>>>> > >>>>>>>> @Inject > >>>>>>>> private ICachingAbiDataProvider<Personen> personenProvider; > >>>>>>>> ... > >>>>>>>> } > >>>>>>>> > >>>>>>>> public class AbstractProvider<E extends JPAEntity> extends > >>>>>>>> SortableDataProvider<E, String> implements IAbiDataProvider<E> { > >>>>>>>> > >>>>>>>> @Inject > >>>>>>>> private ReadOnlyDao<E> dao; > >>>>>>>> ... > >>>>>>>> } > >>>>>>>> > >>>>>>>> public abstract class JPAReadOnlyDao<E extends JPAEntity> > >> implements > >>>>>>>> ReadOnlyDao<E> { > >>>>>>>> > >>>>>>>> private Provider<EntityManager> emProvider; > >>>>>>>> private final Class<E> entityClass; > >>>>>>>> > >>>>>>>> public JPAReadOnlyDao(Class<E> entityClass) { > >>>>>>>> this.entityClass = entityClass; > >>>>>>>> } > >>>>>>>> ... > >>>>>>>> > >>>>>>>> @Inject > >>>>>>>> public void setEntityManagerProvider(Provider<EntityManager> > >>>>>>>> emProvider) { > >>>>>>>> this.emProvider = emProvider; > >>>>>>>> } > >>>>>>>> ... > >>>>>>>> } > >>>>>>>> > >>>>>>>> public class Abi81GuiceModule extends AbstractModule { > >>>>>>>> > >>>>>>>> @Override > >>>>>>>> protected void configure() { > >>>>>>>> bind(PersistServiceInitializer.class).asEagerSingleton(); > >>>>>>>> bind(new TypeLiteral<ReadOnlyDao<Abiartikel>>() > >>>>>>>> {}).to(AbiartikelDao.class); > >>>>>>>> bind(new TypeLiteral<ReadOnlyDao<Personen>>() > >>>>>>>> {}).to(PersonenDao.class); > >>>>>>>> bind(new TypeLiteral<WritingDao<Personen>>() > >>>>>>>> {}).to(PersonenDao.class); > >>>>>>>> bind(new TypeLiteral<ICachingAbiDataProvider<Abiartikel>>() > >>>>>>>> {}).to(CachingAbiartikelProvider.class); > >>>>>>>> bind(new TypeLiteral<ICachingAbiDataProvider<Personen>>() > >>>>>>>> {}).to(CachingPersonenProvider.class); > >>>>>>>> } > >>>>>>>> } > >>>>>>>> > >>>>>>>> BasePage creates a SignInPanel that links to a SignIn-Page, that > >> uses > >>>>>>>> methods of SignInSession, that makes use a PersonenDao in only in > a > >>>>>>>> method. > >>>>>>>> > >>>>>>>> I also made a gist: > >>>>>>>> https://gist.github.com/tremel/dd9bfa252282b5853d6d464feccaad29 > >>>>>>>> > >>>>>>>> Thank you > >>>>>>>> Dieter > >>>>>>>> > >>>>>>>> > >>>>>>>> Am 15.06.2016 um 08:17 schrieb Bas Gooren: > >>>>>>>>> Dieter, > >>>>>>>>> > >>>>>>>>> Since the data provider is inject as a proxy, only the proxy > >> should be > >>>>>>>>> serialized. On deserialization it should look up the actual data > >>>>>>>>> provider again. > >>>>>>>>> > >>>>>>>>> Can you share some code so we can see how you set things up? What > >> you > >>>>>>>>> are trying is something that should work out of the box - it does > >> for > >>>>>>>>> us. > >>>>>>>>> > >>>>>>>>> Bas > >>>>>>>>> > >>>>>>>>> Verstuurd vanaf mijn iPhone > >>>>>>>>> > >>>>>>>>>> Op 15 jun. 2016 om 07:53 heeft Dieter Tremel < > >>>>>> tre...@tremel-computer.de <mailto:tre...@tremel-computer.de>> het > >>>> volgende geschreven: > >>>>>>>>>> > >>>>>>>>>> Hallo wicket-user, > >>>>>>>>>> > >>>>>>>>>> IMHO combining wicket with non serializable objects is a > >> challenging > >>>>>> topic. > >>>>>>>>>> > >>>>>>>>>> On a page I have a DataProvider, that is injected by > >> wicked-guice. > >>>>>>>>>> Inside this provider an injected dao is used for fetching the > >> data. > >>>>>>>>>> Inside the dao a provider for a JPA2 entity manager > >> (EclipseLink) is > >>>>>>>>>> injected. > >>>>>>>>>> > >>>>>>>>>> Page -> DataProvider -> Dao -> Provider<EntityManager> > >>>>>>>>>> > >>>>>>>>>> Seems to be useful, but since the page is stateful I recognized > >> the > >>>>>> non > >>>>>>>>>> serializeable error for the dao at the end of page rendering. > >>>>>>>>>> > >>>>>>>>>> After some code studies I think wicket-guice is only using a > >> proxy > >>>>>> for > >>>>>>>>>> the DataProvider, the second second and third level of injection > >> is > >>>>>> done > >>>>>>>>>> only by guice, not handled by wicket-guice and wicket-ioc. This > >>>>>> causes > >>>>>>>>>> serializable error for dao. Am I right here? wicket-guice is not > >> as > >>>>>>>>>> useful as it could be, if it would not be restricted to the > >> fields in > >>>>>>>>>> the first level. Setter injection is another topic. The > name-pair > >>>>>> lets > >>>>>>>>>> associate a transparent combination of the two technologies, but > >> it > >>>>>> isn't. > >>>>>>>>>> > >>>>>>>>>> At the moment I have no solution for this. > >>>>>>>>>> I still struggle with the right architecture fore using generic > >> JPA2 > >>>>>>>>>> provided entities on my pages. The only idea so far is not to > use > >>>>>> guice > >>>>>>>>>> and use the application as a link to the non serializable JPA > >> objects > >>>>>>>>>> and using detachable models to handle the on pages. > >>>>>>>>>> > >>>>>>>>>> Any hints for my confused mind welcome. Thanks! > >>>>>>>>>> > >>>>>>>>>> Dieter Tremel > > --------------------------------------------------------------------- > To unsubscribe, e-mail: users-unsubscr...@wicket.apache.org > For additional commands, e-mail: users-h...@wicket.apache.org > >
