Re: Anybody know what is this situation?

2009-07-17 Thread Michał Letyński 
I got the same error. It's also totally random. But i have a bit 
different situation.
In my page i have panel, inside this panel i got panel which is 
anonymous class and inside of this panel is InlineFrame with Page.

Any clues how to solve this ?


Jeremy Thomerson pisze:

Generally unexplained class issues like this are because the same
class gets loaded a second time from a different class loader.  I once
had it throwing a ClassCastException that ClassA != ClassA.  Hard to
track down, though.

--
Jeremy Thomerson
http://www.wickettraining.com




On Fri, Jul 3, 2009 at 4:27 PM, bgoorenb...@iswd.nl wrote:
  

I got the same error today, seems totally random.

The only possible explanation I have is that maybe the subclass (LoginPage$1
in your case) stores a PageHolder class instead of the actual page
(LoginPage) when serialized, and when LoginPage$1 is deserialized, the
PageHolder retrieves/points to a different Page.

I was just as baffled as you since in my case the two classes were totally
different, like in your case (com.application.MainPage vs
wicket.quickstart.LoginPage).
In my case it's two pages from the same application, but they are
functionally separate and never interact.

In my case I made the inner class that caused the problem a static inner
class. Since I have been unable to reproduce the problem I cannot confirm if
this resolves the problem.

Can you share what kind of class LoginPage$1 is? (it's the first anonymous
inner class in LoginPage) Is it a class which extends IModel?

Also, you someone from the Wicket team confirm if my explanation above is
possible at all (PageHolder retrieving a different class when
deserializing)?

Bas


MartinM wrote:


Anybody know what is this situation? Wicket 1.4-rc4

From production:

2009-05-18 16:32:44,316 19598423 [btpool0-112] ERROR RequestCycle  -
cannot assign instance of com.application.MainPage to field
wicket.quickstart.LoginPage$1.this$0 of type
wicket.quickstart.LoginPage in instance of
wicket.quickstart.LoginPage$1
java.lang.ClassCastException: cannot assign instance of
com.application.MainPage to field wicket.quickstart.LoginPage$1.this$0
of type wicket.quickstart.LoginPage in instance of
wicket.quickstart.LoginPage$1
   at
java.io.ObjectStreamClass$FieldReflector.setObjFieldValues(ObjectStreamClass.java:2032)
   at
java.io.ObjectStreamClass.setObjFieldValues(ObjectStreamClass.java:1212)

.. etc ...

  

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Re: Anybody know what is this situation?

2009-07-03 Thread bgooren 

I got the same error today, seems totally random.

The only possible explanation I have is that maybe the subclass (LoginPage$1
in your case) stores a PageHolder class instead of the actual page
(LoginPage) when serialized, and when LoginPage$1 is deserialized, the
PageHolder retrieves/points to a different Page.

I was just as baffled as you since in my case the two classes were totally
different, like in your case (com.application.MainPage vs
wicket.quickstart.LoginPage).
In my case it's two pages from the same application, but they are
functionally separate and never interact.

In my case I made the inner class that caused the problem a static inner
class. Since I have been unable to reproduce the problem I cannot confirm if
this resolves the problem.

Can you share what kind of class LoginPage$1 is? (it's the first anonymous
inner class in LoginPage) Is it a class which extends IModel?

Also, you someone from the Wicket team confirm if my explanation above is
possible at all (PageHolder retrieving a different class when
deserializing)?

Bas


MartinM wrote:
 
 Anybody know what is this situation? Wicket 1.4-rc4
 
 From production:
 
 2009-05-18 16:32:44,316 19598423 [btpool0-112] ERROR RequestCycle  -
 cannot assign instance of com.application.MainPage to field
 wicket.quickstart.LoginPage$1.this$0 of type
 wicket.quickstart.LoginPage in instance of
 wicket.quickstart.LoginPage$1
 java.lang.ClassCastException: cannot assign instance of
 com.application.MainPage to field wicket.quickstart.LoginPage$1.this$0
 of type wicket.quickstart.LoginPage in instance of
 wicket.quickstart.LoginPage$1
at
 java.io.ObjectStreamClass$FieldReflector.setObjFieldValues(ObjectStreamClass.java:2032)
at
 java.io.ObjectStreamClass.setObjFieldValues(ObjectStreamClass.java:1212)
 
 .. etc ...
 

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Re: Anybody know what is this situation?

2009-07-03 Thread Jeremy Thomerson 
Generally unexplained class issues like this are because the same
class gets loaded a second time from a different class loader.  I once
had it throwing a ClassCastException that ClassA != ClassA.  Hard to
track down, though.

--
Jeremy Thomerson
http://www.wickettraining.com




On Fri, Jul 3, 2009 at 4:27 PM, bgoorenb...@iswd.nl wrote:

 I got the same error today, seems totally random.

 The only possible explanation I have is that maybe the subclass (LoginPage$1
 in your case) stores a PageHolder class instead of the actual page
 (LoginPage) when serialized, and when LoginPage$1 is deserialized, the
 PageHolder retrieves/points to a different Page.

 I was just as baffled as you since in my case the two classes were totally
 different, like in your case (com.application.MainPage vs
 wicket.quickstart.LoginPage).
 In my case it's two pages from the same application, but they are
 functionally separate and never interact.

 In my case I made the inner class that caused the problem a static inner
 class. Since I have been unable to reproduce the problem I cannot confirm if
 this resolves the problem.

 Can you share what kind of class LoginPage$1 is? (it's the first anonymous
 inner class in LoginPage) Is it a class which extends IModel?

 Also, you someone from the Wicket team confirm if my explanation above is
 possible at all (PageHolder retrieving a different class when
 deserializing)?

 Bas


 MartinM wrote:

 Anybody know what is this situation? Wicket 1.4-rc4

 From production:

 2009-05-18 16:32:44,316 19598423 [btpool0-112] ERROR RequestCycle  -
 cannot assign instance of com.application.MainPage to field
 wicket.quickstart.LoginPage$1.this$0 of type
 wicket.quickstart.LoginPage in instance of
 wicket.quickstart.LoginPage$1
 java.lang.ClassCastException: cannot assign instance of
 com.application.MainPage to field wicket.quickstart.LoginPage$1.this$0
 of type wicket.quickstart.LoginPage in instance of
 wicket.quickstart.LoginPage$1
        at
 java.io.ObjectStreamClass$FieldReflector.setObjFieldValues(ObjectStreamClass.java:2032)
        at
 java.io.ObjectStreamClass.setObjFieldValues(ObjectStreamClass.java:1212)

 .. etc ...


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Anybody know what is this situation?

2009-05-18 Thread Martin Makundi 
Anybody know what is this situation? Wicket 1.4-rc4

From production:

2009-05-18 16:32:44,316 19598423 [btpool0-112] ERROR RequestCycle  -
cannot assign instance of com.application.MainPage to field
wicket.quickstart.LoginPage$1.this$0 of type
wicket.quickstart.LoginPage in instance of
wicket.quickstart.LoginPage$1
java.lang.ClassCastException: cannot assign instance of
com.application.MainPage to field wicket.quickstart.LoginPage$1.this$0
of type wicket.quickstart.LoginPage in instance of
wicket.quickstart.LoginPage$1
   at 
java.io.ObjectStreamClass$FieldReflector.setObjFieldValues(ObjectStreamClass.java:2032)
   at 
java.io.ObjectStreamClass.setObjFieldValues(ObjectStreamClass.java:1212)
   at 
java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1953)
   at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1871)
   at 
java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1753)
   at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1329)
   at java.io.ObjectInputStream.readArray(ObjectInputStream.java:1667)
   at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1323)
   at 
java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1947)
   at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1871)
   at 
java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1753)
   at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1329)
   at 
java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1947)
   at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1871)
   at 
java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1753)
   at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1329)
   at 
java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1947)
   at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1871)
   at 
java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1753)
   at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1329)
   at 
java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1947)
   at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1871)
   at 
java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1753)
   at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1329)
   at java.io.ObjectInputStream.readArray(ObjectInputStream.java:1667)
   at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1323)
   at 
java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1947)
   at 
java.io.ObjectInputStream.defaultReadObject(ObjectInputStream.java:480)
   at org.apache.wicket.Component.readObject(Component.java:4470)
   at sun.reflect.GeneratedMethodAccessor107.invoke(Unknown Source)
   at 
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
   at java.lang.reflect.Method.invoke(Method.java:597)
   at java.io.ObjectStreamClass.invokeReadObject(ObjectStreamClass.java:974)
   at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1849)
   at 
java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1753)
   at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1329)
   at 
java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1947)
   at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1871)
   at 
java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1753)
   at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1329)
   at 
java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1947)
   at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1871)
   at 
java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1753)
   at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1329)
   at 
java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1947)
   at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1871)
   at 
java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1753)
   at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1329)
   at java.io.ObjectInputStream.readArray(ObjectInputStream.java:1667)
   at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1323)
   at 
java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1947)
   at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1871)
   at 
java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1753)
   at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1329)
   at java.io.ObjectInputStream.readArray(ObjectInputStream.java:1667

Re: Anybody know what is this situation?

2009-05-18 Thread Serkan Camurcuoglu 
In my experience such unexpected classcastexceptions may occur if the 
same class is loaded twice by different classloaders.. Check whether the 
LoginPage class exists in both WEB-INF/classes and some other jar in 
your classpath..



Martin Makundi wrote:

Anybody know what is this situation? Wicket 1.4-rc4

From production:

2009-05-18 16:32:44,316 19598423 [btpool0-112] ERROR RequestCycle  -
cannot assign instance of com.application.MainPage to field
wicket.quickstart.LoginPage$1.this$0 of type
wicket.quickstart.LoginPage in instance of
wicket.quickstart.LoginPage$1
java.lang.ClassCastException: cannot assign instance of
com.application.MainPage to field wicket.quickstart.LoginPage$1.this$0
of type wicket.quickstart.LoginPage in instance of
wicket.quickstart.LoginPage$1
   at 
java.io.ObjectStreamClass$FieldReflector.setObjFieldValues(ObjectStreamClass.java:2032)
   at 
java.io.ObjectStreamClass.setObjFieldValues(ObjectStreamClass.java:1212)
   at 
java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1953)
   at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1871)
   at 
java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1753)
   at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1329)
   at java.io.ObjectInputStream.readArray(ObjectInputStream.java:1667)
   at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1323)
   at 
java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1947)
   at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1871)
   at 
java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1753)
   at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1329)
   at 
java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1947)
   at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1871)
   at 
java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1753)
   at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1329)
   at 
java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1947)
   at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1871)
   at 
java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1753)
   at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1329)
   at 
java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1947)
   at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1871)
   at 
java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1753)
   at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1329)
   at java.io.ObjectInputStream.readArray(ObjectInputStream.java:1667)
   at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1323)
   at 
java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1947)
   at 
java.io.ObjectInputStream.defaultReadObject(ObjectInputStream.java:480)
   at org.apache.wicket.Component.readObject(Component.java:4470)
   at sun.reflect.GeneratedMethodAccessor107.invoke(Unknown Source)
   at 
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
   at java.lang.reflect.Method.invoke(Method.java:597)
   at java.io.ObjectStreamClass.invokeReadObject(ObjectStreamClass.java:974)
   at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1849)
   at 
java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1753)
   at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1329)
   at 
java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1947)
   at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1871)
   at 
java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1753)
   at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1329)
   at 
java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1947)
   at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1871)
   at 
java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1753)
   at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1329)
   at 
java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1947)
   at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1871)
   at 
java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1753)
   at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1329)
   at java.io.ObjectInputStream.readArray(ObjectInputStream.java:1667)
   at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1323)
   at 
java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1947)
   at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1871

Re: Anybody know what is this situation?

2009-05-18 Thread Martin Makundi 
I found only one instance.

Does it matter that it is a random exception (i.e., I saw it first
time today and the app has been running for a long time)?

**
Martin

2009/5/18 Serkan Camurcuoglu serkan.camurcuo...@telenity.com:
 In my experience such unexpected classcastexceptions may occur if the same
 class is loaded twice by different classloaders.. Check whether the
 LoginPage class exists in both WEB-INF/classes and some other jar in your
 classpath..


 Martin Makundi wrote:

 Anybody know what is this situation? Wicket 1.4-rc4

 From production:

 2009-05-18 16:32:44,316 19598423 [btpool0-112] ERROR RequestCycle  -
 cannot assign instance of com.application.MainPage to field
 wicket.quickstart.LoginPage$1.this$0 of type
 wicket.quickstart.LoginPage in instance of
 wicket.quickstart.LoginPage$1
 java.lang.ClassCastException: cannot assign instance of
 com.application.MainPage to field wicket.quickstart.LoginPage$1.this$0
 of type wicket.quickstart.LoginPage in instance of
 wicket.quickstart.LoginPage$1
   at
 java.io.ObjectStreamClass$FieldReflector.setObjFieldValues(ObjectStreamClass.java:2032)
   at
 java.io.ObjectStreamClass.setObjFieldValues(ObjectStreamClass.java:1212)
   at
 java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1953)
   at
 java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1871)
   at
 java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1753)
   at
 java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1329)
   at java.io.ObjectInputStream.readArray(ObjectInputStream.java:1667)
   at
 java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1323)
   at
 java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1947)
   at
 java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1871)
   at
 java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1753)
   at
 java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1329)
   at
 java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1947)
   at
 java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1871)
   at
 java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1753)
   at
 java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1329)
   at
 java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1947)
   at
 java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1871)
   at
 java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1753)
   at
 java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1329)
   at
 java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1947)
   at
 java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1871)
   at
 java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1753)
   at
 java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1329)
   at java.io.ObjectInputStream.readArray(ObjectInputStream.java:1667)
   at
 java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1323)
   at
 java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1947)
   at
 java.io.ObjectInputStream.defaultReadObject(ObjectInputStream.java:480)
   at org.apache.wicket.Component.readObject(Component.java:4470)
   at sun.reflect.GeneratedMethodAccessor107.invoke(Unknown Source)
   at
 sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
   at java.lang.reflect.Method.invoke(Method.java:597)
   at
 java.io.ObjectStreamClass.invokeReadObject(ObjectStreamClass.java:974)
   at
 java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1849)
   at
 java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1753)
   at
 java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1329)
   at
 java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1947)
   at
 java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1871)
   at
 java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1753)
   at
 java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1329)
   at
 java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1947)
   at
 java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1871)
   at
 java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1753)
   at
 java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1329)
   at
 java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1947)
   at
 java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1871)
   at
 java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1753)
   at
 java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1329)
   at java.io.ObjectInputStream.readArray(ObjectInputStream.java