Forgive my lack of understanding of Wicket internals, but do requests for Ajax components on a particular page block when that page is being serialized?
Matej Knopp-2 wrote: > > This really looks like page being accessed from multiple threads, but > it's quite weird. The serialization is done in request thread and > pagemap is locked during request. > > -Matej > > On Thu, Dec 18, 2008 at 2:35 PM, leok <leo...@gmail.com> wrote: >> >> Interesting. I wonder if this error occurs when page components are being >> modified by Ajax while being serialized, e.g. page.addOrReplace(). If so, >> this is kind of an ugly bug. What I don't know yet is how "harmful" this >> bug >> is, i.e. does this error leave Wicket in a horribly inconsistent state? >> >> >> >> Xhelas wrote: >>> >>> Same symptoms using wocket 1.4-rc1. >>> >>> Regards >>> >>> Alexandre >>> >>> >>> leok wrote: >>>> >>>> I was poking through some logs, and I noticed a few rare instances of >>>> this exception: >>>> >>>> java.util.ConcurrentModificationException >>>> at >>>> java.util.LinkedHashMap$LinkedHashIterator.nextEntry(LinkedHashMap.java:365) >>>> at java.util.LinkedHashMap$KeyIterator.next(LinkedHashMap.java:376) >>>> at java.util.HashSet.writeObject(HashSet.java:254) >>>> at sun.reflect.GeneratedMethodAccessor3239.invoke(Unknown Source) >>>> at >>>> sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) >>>> at java.lang.reflect.Method.invoke(Method.java:585) >>>> at >>>> java.io.ObjectStreamClass.invokeWriteObject(ObjectStreamClass.java:917) >>>> at >>>> java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1344) >>>> at >>>> java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1295) >>>> at >>>> java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1084) >>>> at >>>> java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1380) >>>> at >>>> java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1352) >>>> at >>>> java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1295) >>>> at >>>> java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1084) >>>> at >>>> java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1380) >>>> at >>>> java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1352) >>>> at >>>> java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1295) >>>> at >>>> java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1084) >>>> at >>>> java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:307) >>>> at java.util.HashMap.writeObject(HashMap.java:1328) >>>> at sun.reflect.GeneratedMethodAccessor3234.invoke(Unknown Source) >>>> at >>>> sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) >>>> at java.lang.reflect.Method.invoke(Method.java:585) >>>> at >>>> java.io.ObjectStreamClass.invokeWriteObject(ObjectStreamClass.java:917) >>>> at >>>> java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1344) >>>> [..snip..] >>>> at >>>> java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:307) >>>> at >>>> org.apache.wicket.util.io.IObjectStreamFactory$2.writeObjectOverride(IObjectStreamFactory.java:117) >>>> at >>>> java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:303) >>>> at >>>> org.apache.wicket.util.lang.Objects.objectToByteArray(Objects.java:1091) >>>> at >>>> org.apache.wicket.protocol.http.pagestore.AbstractPageStore$PageSerializer.getPageReplacementObject(AbstractPageStore.java:278) >>>> at org.apache.wicket.Page.writeReplace(Page.java:1299) >>>> at sun.reflect.GeneratedMethodAccessor6627.invoke(Unknown Source) >>>> at >>>> sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) >>>> at java.lang.reflect.Method.invoke(Method.java:585) >>>> at >>>> java.io.ObjectStreamClass.invokeWriteReplace(ObjectStreamClass.java:1004) >>>> [..snip..] >>>> at >>>> org.apache.wicket.util.lang.Objects.objectToByteArray(Objects.java:1091) >>>> at >>>> org.apache.wicket.protocol.http.pagestore.AbstractPageStore.serializePage(AbstractPageStore.java:197) >>>> at >>>> org.apache.wicket.protocol.http.pagestore.DiskPageStore.storePage(DiskPageStore.java:811) >>>> at >>>> org.apache.wicket.protocol.http.SecondLevelCacheSessionStore$SecondLevelCachePageMap.put(SecondLevelCacheSessionStore.java:332) >>>> >>>> I'm using Wicket 1.3.5. It seems there might be some strange racing >>>> happening while pages are being serialized. >>>> >>>> EDIT: I actually posted before completing my message. I meant to add - >>>> where would there be non thread-safe modifications to the serialized >>>> page? I presume that the there must be some sort of lock on the object >>>> when it's being serialized. More importantly - how "harmful" is this >>>> exception? >>>> >>> >>> >> >> -- >> View this message in context: >> http://www.nabble.com/java.util.ConcurrentModificationException-inorg.apache.wicket.protocol.http.SecondLevelCacheSessionStore%24SecondLevelCachePageMap.put-tp21062585p21072905.html >> Sent from the Wicket - User mailing list archive at Nabble.com. >> >> >> --------------------------------------------------------------------- >> To unsubscribe, e-mail: users-unsubscr...@wicket.apache.org >> For additional commands, e-mail: users-h...@wicket.apache.org >> >> > > --------------------------------------------------------------------- > To unsubscribe, e-mail: users-unsubscr...@wicket.apache.org > For additional commands, e-mail: users-h...@wicket.apache.org > > > -- View this message in context: http://www.nabble.com/java.util.ConcurrentModificationException-inorg.apache.wicket.protocol.http.SecondLevelCacheSessionStore%24SecondLevelCachePageMap.put-tp21062585p21077839.html Sent from the Wicket - User mailing list archive at Nabble.com. --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@wicket.apache.org For additional commands, e-mail: users-h...@wicket.apache.org
