PQ56607: WHEN USING VERSION 2.03 CONNECTION MANAGER WITH WEBSPHERE 3.5.3,SYSTEM HANGS WITH NULLPOINTEREXCEPTION

A fix is available
3.5.4-3.5.7, 4.0.2-4.0.7: Component cumulative Connection Manager fix

APAR

APAR status
Closed as program error.

Error description
System hanging due to NullPointerException when using Websphere
2.0 Connection Manager in Websphere 3.5.3.  This happens when a
connection is released back to the pool.  Error stack trace is
as follows:
ServletInstan X Uncaught service() exception root cause {0}: {1}
"jsp10"
java.lang.NullPointerException
at com.ibm.ejs.dbm.util.Queue.remove(Queue.java:228)
at com.ibm.ejs.dbm.jdbcext.ConnectionPool.ReturnConnectionToFree
(ConnectionPool.java:1728)
at com.ibm.ejs.dbm.was20.WAS20ConnPool.releaseConnectionObject(W
ConnPool.java:94)
at com.ibm.ejs.dbm.was20.WAS20Connector.releaseConnectionObject(
Connector.java:100)
at com.ibm.servlet.connmgr.IBMConnMgr.releaseIBMConnection(IBMCo
java:115)
at com.ibm.servlet.connmgr.IBMConnection.releaseIBMConnection(IB
ection.java:116)
at com.ibm.ls.igc.servlets.CommonContentBean.getContent(CommonCo
Bean.java:156)
This error will only occur when a WAS 3.5.x user is using the
2.0 Connection Manager API.  Must have PQ55402 for this fix.
.
KEYWORDS: WAS Websphere 203 2.03 2.0.3 353 350 3.5 3.5.3 3.5.x
as follows:ServletInstan X Uncaught service() exception root cause {0}: {1}"jsp10"java.lang.NullPointerExceptionat com.ibm.ejs.dbm.util.Queue.remove(Queue.java:228)at com.ibm.ejs.dbm.jdbcext.ConnectionPool.ReturnConnectionToFree(ConnectionPool.java:1728)at com.ibm.ejs.dbm.was20.WAS20ConnPool.releaseConnectionObject(WConnPool.java:94)at com.ibm.ejs.dbm.was20.WAS20Connector.releaseConnectionObject(Connector.java:100)at com.ibm.servlet.connmgr.IBMConnMgr.releaseIBMConnection(IBMCojava:115)at com.ibm.servlet.connmgr.IBMConnection.releaseIBMConnection(IBection.java:116)at com.ibm.ls.igc.servlets.CommonContentBean.getContent(CommonCoBean.java:156)This error will only occur when a WAS 3.5.x user is using the, 2.0 Connection Manager API. Must havePQ55402, for this fix..KEYWORDS: WAS Websphere 203 2.03 2.0.3 353 350 3.5 3.5.3 3.5.x
Local fix
Problem summary
****************************************************************
* USERS AFFECTED: WebSphere Application Server users of the    *
*                 2.0 ConnMgr API from WebSphere 2.0           *
****************************************************************
* PROBLEM DESCRIPTION: NullPointer exceptions may be           *
*                      received when getting a connection.     *
****************************************************************
* RECOMMENDATION:                                              *
****************************************************************
Applications that use the WebSphere 2.0 IBMConnMgr
interfaces to get and release connections from the same
connection pool and the gets and release may occur
in overlapping requests, i.e. a get is occurring while
a release is occurring, may receive NullPointer exceptions.
Problem conclusion
The WAS20 Connection wrappers were bypassing some of
the synchronization in the 3.5 dbm code and had synchronization
added to the wrappers to try to enforce synchronization in the
wrapper layer but this was not quite correct.  The releases
were being synchronized and the removes were synchronized
(sort of) but the gets were not synchronized at all nor was
interaction between the gets, releases and removes synchronized
at all.  Synchronization was added to WAS20Connector in order
to make sure all requests were being synchronized.
Temporary fix
Comments
APAR information
APAR numberPQ56607
Reported component nameWAS ADVANCED AI
Reported component ID5648C8400
Reported release350
StatusCLOSED PER
PENoPE
HIPERNoHIPER
Submitted date2002-01-11
Closed date2002-01-22
Last modified date2002-01-22

APAR is sysrouted FROM one or more of the following:

APAR is sysrouted TO one or more of the following:APAR is sysrouted FROM one or more of the following:


Modules/Macros
JDBC
APAR is sysrouted TO one or more of the following:Modules/Macros

Fix information
Fixed component nameWAS ADVANCED AI
Fixed component ID5648C8400

Applicable component levels
R350 PSYUP











Document Information

Product categories: Software, Application Servers, Distributed Application & Web Servers, WebSphere Application Server, General
Software version: 350
Reference #: PQ56607
IBM Group: Software Group
Modified date: 2002-01-22