Re: Session error while loading an object

2010-07-14 Thread abhishek jain 
On Wed, Jul 14, 2010 at 1:39 AM, Peter Crowther peter.crowt...@melandra.com
 wrote:

 On 13 July 2010 16:15, abhishek jain abhishek.netj...@gmail.com wrote:

  On Tue, Jul 13, 2010 at 2:11 PM, Peter Crowther 
  peter.crowt...@melandra.com
   wrote:
 
   On 13 July 2010 09:34, abhishek jain abhishek.netj...@gmail.com
 wrote:
  
I am using tomcat 5.5 , struts 1.x and i encounter the following
 error:
I actually store the object in session and retrieve that(for a
 shopping
cart
application), pl. advice what i can do to remove this error:
   
java.io.NotSerializableException: com.cart.Customer
   
  
   You need to make sure that com.cart.Customer (and anything else you
 store
   in
   the session) is serializable.
  
   - Peter
  
 
  Thanks Peter,
  i will check but i get this error only at times, and not always.
  Can this still be the cause of the problem.
  thanks
  abhishek
 

 Yes.  It's happening because your webapp is being reloaded (are you
 changing
 some part of it?) and there are active sessions.  The sessions are
 serialised to persist them; then the webapp is restarted; then the sessions
 are deserialised.

 If there are no sessions at the time the webapp is restarted, the problem
 will not occur.

 - Peter



Thanks Peter for the info,
I just realized that i am having in the Cart object which i save in session,
references of datasource and message resources.
This is creating the problem as they i believe are not serializable,
Is there any way of overcoming them.
Pl. advice,
thanks
abhishek

Re: Session error while loading an object

2010-07-14 Thread Peter Crowther 
On 14 July 2010 08:02, abhishek jain abhishek.netj...@gmail.com wrote:

 I just realized that i am having in the Cart object which i save in
 session,
 references of datasource and message resources.
 This is creating the problem as they i believe are not serializable,
 Is there any way of overcoming them.

 They're not serializable for a good reason - you shouldn't really be
keeping references to system resources between requests.  As you've found
out, the session can be serialized at any time, and it may be deserialized a
long time later - potentially even after the application has been
restarted.  At this point, the references to datasources and message
resources may no longer be valid.

Why are you keeping references to the datasource and message resources in
the Cart now?  Can you re-think your design of the Cart so that it keeps
only serializable data between requests?

- Peter

Session error while loading an object

2010-07-13 Thread abhishek jain 
Hi friends,
I am using tomcat 5.5 , struts 1.x and i encounter the following error:
I actually store the object in session and retrieve that(for a shopping cart
application), pl. advice what i can do to remove this error:

Exception loading sessions from persistent
storagejava.io.WriteAbortedException: writing aborted;
java.io.NotSerializableException: com.cart.Customer
   at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1333)
   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.readObject(ObjectInputStream.java:351)
   at
org.apache.catalina.session.StandardSession.readObject(StandardSession.java:1416)
   at
org.apache.catalina.session.StandardSession.readObjectData(StandardSession.java:940)
   at
org.apache.catalina.session.StandardManager.doLoad(StandardManager.java:394)
   at
org.apache.catalina.session.StandardManager.load(StandardManager.java:321)
   at
org.apache.catalina.session.StandardManager.start(StandardManager.java:637)
   at
org.apache.catalina.core.StandardContext.start(StandardContext.java:4202)
   at
org.apache.catalina.core.StandardContext.reload(StandardContext.java:3056)
   at
org.apache.catalina.loader.WebappLoader.backgroundProcess(WebappLoader.java:432)
   at
org.apache.catalina.core.ContainerBase.backgroundProcess(ContainerBase.java:1278)
   at
org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren(ContainerBase.java:1570)
   at
org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren(ContainerBase.java:1579)
   at
org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren(ContainerBase.java:1579)
   at
org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.run(ContainerBase.java:1559)
   at java.lang.Thread.run(Thread.java:619)
Caused by: java.io.NotSerializableException: com.cart.Customer
   at
java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1156)
   at
java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1509)
   at
java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1474)
   at
java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1392)
   at
java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1150)
   at
java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:326)
   at
org.apache.catalina.session.StandardSession.writeObject(StandardSession.java:1492)
   at
org.apache.catalina.session.StandardSession.writeObjectData(StandardSession.java:957)
   at
org.apache.catalina.session.StandardManager.doUnload(StandardManager.java:517)
   at
org.apache.catalina.session.StandardManager.unload(StandardManager.java:463)
   at
org.apache.catalina.session.StandardManager.stop(StandardManager.java:667)
   at
org.apache.catalina.core.StandardContext.stop(StandardContext.java:4362)
   at
org.apache.catalina.core.StandardContext.reload(StandardContext.java:3050)
   ... 7 more



-- 
Thanks and kind Regards,
Abhishek jain

Re: Session error while loading an object

2010-07-13 Thread abhishek jain 
On Tue, Jul 13, 2010 at 2:11 PM, Peter Crowther peter.crowt...@melandra.com
 wrote:

 On 13 July 2010 09:34, abhishek jain abhishek.netj...@gmail.com wrote:

  I am using tomcat 5.5 , struts 1.x and i encounter the following error:
  I actually store the object in session and retrieve that(for a shopping
  cart
  application), pl. advice what i can do to remove this error:
 
  java.io.NotSerializableException: com.cart.Customer
 

 You need to make sure that com.cart.Customer (and anything else you store
 in
 the session) is serializable.

 - Peter


Thanks Peter,
i will check but i get this error only at times, and not always.
Can this still be the cause of the problem.
thanks
abhishek

Re: Session error while loading an object

2010-07-13 Thread Peter Crowther 
On 13 July 2010 16:15, abhishek jain abhishek.netj...@gmail.com wrote:

 On Tue, Jul 13, 2010 at 2:11 PM, Peter Crowther 
 peter.crowt...@melandra.com
  wrote:

  On 13 July 2010 09:34, abhishek jain abhishek.netj...@gmail.com wrote:
 
   I am using tomcat 5.5 , struts 1.x and i encounter the following error:
   I actually store the object in session and retrieve that(for a shopping
   cart
   application), pl. advice what i can do to remove this error:
  
   java.io.NotSerializableException: com.cart.Customer
  
 
  You need to make sure that com.cart.Customer (and anything else you store
  in
  the session) is serializable.
 
  - Peter
 

 Thanks Peter,
 i will check but i get this error only at times, and not always.
 Can this still be the cause of the problem.
 thanks
 abhishek


Yes.  It's happening because your webapp is being reloaded (are you changing
some part of it?) and there are active sessions.  The sessions are
serialised to persist them; then the webapp is restarted; then the sessions
are deserialised.

If there are no sessions at the time the webapp is restarted, the problem
will not occur.

- Peter