Fix (APAR):  PK53807

Status:  Fix

Release:  6.1.0.11

Operating System:  AIX,Linux,Solaris,Windows

Supersedes Fixes:  PK52238, PK53626, PK54131, PK53626, PK51406, PK48850, PK53717, PK50423, PK50333, PK49009

CMVC Defect:  xxxxxx

Byte size of APAR:  344006

Date: 2007-10-23

Abstract:  ConcurrentModificationException when using collection returned from SipApplicationSession.getTimers.

Description/symptom of problem:  
PK53807 resolves the following problem:

ERROR DESCRIPTION:                                              
When traversing the timers collection, after retrieving it using
getTimers() on SipApplicationSession object, got the following  
exception:                                                      
                                                                
Exception = java.util.ConcurrentModificationException           
Source =                                                        
com.ibm.ws.webcontainer.filter.WebAppFilterChain.doFilter       
probeid = 89                                                    
Stack Dump = java.util.ConcurrentModificationException          
        at                                                      
java.util.AbstractList$Itr.checkForComodification(AbstractList.j
ava:464)                                                        
        at                                                      
java.util.AbstractList$Itr.next(AbstractList.java:435)          
        at                                                      
com.ibm.presence.provider.OutgoingSubscriber.getProviderTimer(Ou
tgoingSubscriber.java:1002)                                     
        at                                                      
com.ibm.presence.provider.OutgoingSubscriber.cancelTimer(Outgoin
gSubscriber.java:942)                                           
        at                                                      
com.ibm.presence.provider.OutgoingSubscriber.doErrorResponse(Out
goingSubscriber.java:837)                                       
        at                                                      
com.ibm.presence.rls.GlsSubscriber.doResponse(GlsSubscriber.java
:399)                                                           
        at                                                      
com.ibm.presence.provider.OutgoingSubscribeAgent.doResponse(Outg
oingSubscribeAgent.java:270)                                    
        at                                                      
com.ibm.presence.siplets.NotifySiplet.doResponse(NotifySiplet.ja
va:160)                                                         
        at                                                      
javax.servlet.sip.SipServlet.doResponseWrapper(SipServlet.java:7
94)                                                             
        at                                                      
javax.servlet.sip.SipServlet.service(SipServlet.java:198)       
.....                                                           

LOCAL FIX:                                                      
None                                                            

PROBLEM SUMMARY

USERS AFFECTED:
IBM Websphere Application Server version 6.1
Session Initiation Protocol (SIP) users

PROBLEM DESCRIPTION:
ConcurrentModificationException when
using collection returned from
SipApplicationSession.getTimers.

RECOMMENDATION:
None

Returned collection is not a copy but the same instance
SipApplicationSession holds.
While using this collection, SipApplicationSession can modify
it's timers which will result a ConcurrentModificationException.

PROBLEM CONCLUSION:                                             
getTimes will return a clone of the collection to avoid the     
ConcurrentModificationException.                                
                                                                
The fix for this APAR is currently targeted for inclusion       
in fix pack 6.1.0.15.                                           
Please refer to the recommended updates page for delivery       
information:                                                    
http://www.ibm.com/support/docview.wss?rs=180&uid=swg27004980   


Directions to apply fix:  
NOTE: Choose the:
1) Release the fix applies to
2) The Editions that apply
3) Delete the Editions & Methods that do not apply and this Note

Fix applies to Editions:
Release 6.0
__ Application Server (Express or BASE)
__ Network Deployment (ND)
__ WebSphere Business Integration Server Foundation (WBISF)
__ Edge Components
__ Developer
__ Extended Deployment (XD)

Install Fix to:
Method:
__ Application Server Nodes
__ Deployment Manager Nodes
__ Both

NOTE:
The user must:
* Have Administrative rights in Windows, or be the Actual Root User in a UNIX environments.
* Logged in with the same authority level when unpacking a fix, fix pack or refresh pack.
* Be at V6.0.2.2 or newer of the Update Installer. This can be checked by reviewing the level of the Update Installer in file <was_root>/updateinstaller/version.txt.

The Update Installer can be downloaded from the following link:
http://www.ibm.com/support/docview.wss?rs=180&uid=swg21205991

For detailed instructions to Extract the Update Installer see the following Technote:
http://www-1.ibm.com/support/docview.wss?rs=180&uid=swg21205400

1) Copy PKxxxxx.pak file directly to the maintenance directory

2) Shutdown WebSphere
Manually execute setupCmdLine.bat in Windows or . ./setupCmdLine.sh in Unix from the WebSphere instance that maintenance is being applied to.

3) Launch Update Installer

4) Enter the installation location of the WebSphere product you want to update.

5) Select the "Install maintenance package" operation.

6) Enter the file name of the maintenance package to install (PKxxxxx.pak file which was copied in the maintenance directory).

7) Install the maintenance package.

8) Restart WebSphere

Directions to remove fix:  
NOTE:
* The user must have Administrative rights in Windows, or be the Actual Root User in a UNIX environments.
* FIXES MUST BE REMOVED IN THE ORDER THEY WERE APPLIED
* DO NOT REMOVE A FIX UNLESS ALL FIXES APPLIED AFTER IT HAVE FIRST BEEN REMOVED
* YOU MAY REAPPLY ANY REMOVED FIX

Example: If your system has fix1, fix2, and fix3 applied in that order and fix2 is to be removed, fix3 must be removed first, fix2 removed, and fix3 re-applied.

1) Shutdown WebSphere
Manually execute setupCmdLine.bat in Windows or . ./setupCmdLine.sh in Unix from the WebSphere instance that uninstall is being run against.

2) Start Update Installer

3) Enter the installation location of the WebSphere product you want to remove the fix.

4) Select  "Uninstall maintenance package" operation.

5) Enter the file name of the maintenance package to uninstall (PKxxxxx.pak).

6) UnInstall maintenance package.

7) Restart WebSphere

Directions to re-apply fix:  
1) Shutdown WebSphere.

2) Follow the Fix instructions to apply the fix.

3) Restart WebSphere.



Additional Information: