IC71305: WMQ V7 PUB/SUB: USING XMS CLIENT TO UNSUBSCRIBE GENERATES AN 'OBJECT REFERENCE NOT SET TO AN INSTANCE OF AN OBJECT' ERROR

WebSphere MQ V7.0 Fix Pack 7.0.1.4
WebSphere MQ V7.0.1 for i5/OS Fix Pack 7.0.1.4

APAR status

• Closed as program error.

Error description

• When the XMS client uses two separate threads to subscribe and
  unsubscribe to a subscription, an error is generated.  The error
  seen is 'Object reference not set to an instance of an object'
  and the stack trace of the XMS application shows:
  
  Object reference not set to an instance of an object.
  at IBM.WMQ.MQProxyQueue.ProxyMQCLOSE(Int32 closeOptions,
  Int32&
  compCode, Int32& reason)
  at IBM.WMQ.MQFAP.MQCLOSE(Int32 hConn, Int32 options, Int32
  hObj,
  Int32& compCode, Int32& reason)
  at IBM.WMQ.Nmqi.ManagedNmqiMQ.MQCLOSE(Hconn phConn, Phobj
  phobj,
  Int32 options, Int32& pCompCode, Int32& pReason)
  at IBM.XMS.Client.WMQ.WmqAsyncConsumerShadow.CloseInternal()
  at IBM.XMS.Client.WMQ.WmqConsumerShadow.Close()
  at IBM.XMS.Client.WMQ.WmqMessageConsumer.Close()
  at IBM.XMS.Client.Impl.XmsMessageConsumerImpl.Close()
  at IBM.XMS.Client.Impl.XmsSessionImpl.Dispose(Boolean
  disposing)
  at IBM.XMS.Client.Impl.XmsSessionImpl.Close()
  
  Even though the error is generated, the unsubscribe completes
  successfully.
  

Local fix

Problem summary

• ****************************************************************
  USERS AFFECTED:
  This problem could affect the XMS / .NET client users who are
  using multi threaded applications.
  
  Platforms affected:
  Windows
  
  ****************************************************************
  PROBLEM SUMMARY:
  There is thread specific data stored in the thread context and
  when an exception occurs in the application, this information
  is getting cleared.  This subsequently causes the application
  failure.
  

Problem conclusion

• WebSphere MQ .NET code has been modified with safer way to
  maintain thread specific data.
  
  ---------------------------------------------------------------
  The fix is targeted for delivery in the following PTFs:
  
                     v7.0
  Platform           Fix Pack 7.0.1.4
  --------           --------------------
  Windows            U200323
  
  The latest available maintenance can be obtained from
  'WebSphere MQ Recommended Fixes'
  http://www-1.ibm.com/support/docview.wss?rs=171&uid=swg27006037
  
  If the maintenance level is not yet available, information on
  its planned availability can be found in 'WebSphere MQ
  Planned Maintenance Release Dates'
  http://www-1.ibm.com/support/docview.wss?rs=171&uid=swg27006309
  ---------------------------------------------------------------
  

Temporary fix

Comments

APAR Information

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

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

Fix information

• Fixed component name

  WMQ WINDOWS V7

• Fixed component ID

  5724H7220

Applicable component levels

• R700 PSY

     UP