IT43016: MQ Classes for Java throws a MQRC 2019 exception 'MQRC_HOBJ_ERROR' when attempting to close a queue

APAR status

• Closed as program error.

Error description

• An MQ classes for Java application which is opening and closing
  queues in quick succession occasionally receives the following
  exception which is thrown back from the MQ classes for Java API:
  
  com.ibm.mq.MQException: MQJE001: Completion Code '2', Reason
  '2019'.
  at com.ibm.mq.MQManagedObject.close(MQManagedObject.java:582)
  at com.ibm.mq.MQManagedObject.close(MQManagedObject.java:535)
  at com.ibm.mq.MQQueue.close(MQQueue.java:909)
  at MyApplication.myMethod(MyApplication.java:161)
  
  No exception was thrown to the application when the queue was
  opened, and the application has been able to utilise the queue
  to send and/or receive messages.
  

Local fix

Problem summary

• ****************************************************************
  USERS AFFECTED:
  Users of the IBM MQ Classes for Java API, who are using a
  BINDINGs transport connection to connect to the queue manager.
  
  
  Platforms affected:
  MultiPlatform
  
  ****************************************************************
  PROBLEM DESCRIPTION:
  APAR IT35334 addressed an issue where a heavily multi-threaded
  application which repeatedly opened and closed a queue using the
  MQ classes for Java API method call:
  
    com.ibm.mq.MQQueueManager.accessQueue(String queueName, int
  openOptions)
  
  would occasionally receive an exception indicating that the open
  of the queue had failed with the reason code:
  
    MQRC 2019 'MQRC_HOBJ_ERROR'
  
  com.ibm.mq.MQException: MQJE001: Completion Code '2',
  Reason'2019'.
  at com.ibm.mq.MQDestination.open(MQDestination.java:298)
  at com.ibm.mq.MQQueue.<init>(MQQueue.java:236)
  at
  com.ibm.mq.MQQueueManager.accessQueue(MQQueueManager.java:2740)
  at
  com.ibm.mq.MQQueueManager.accessQueue(MQQueueManager.java:2781)
  at MyApplication.run(MyApplication.java:119)
  
  As a follow on to that problem, the action of closing the queue
  would also sometimes report a MQRC 2019 exception, when the
  application made the method call:
  
    com.ibm.mq.MQQueue.close()
  
  with an exception stack of the form:
  
  com.ibm.mq.MQException: MQJE001: Completion Code '2', Reason
  '2019'.
    at com.ibm.mq.MQManagedObject.close(MQManagedObject.java:582)
    at com.ibm.mq.MQManagedObject.close(MQManagedObject.java:535)
    at com.ibm.mq.MQQueue.close(MQQueue.java:909)
    at MyApplication.myMethod()
  
  and the MQQueue close operation would fail.
  

Problem conclusion

• The MQ classes for Java API has been updated to improve the
  object sharing visibility between threads, such that in an
  environment where an application is making heavy use of the MQ
  classes for Java API with a BINDINGs transport connection to the
  queue manager, the threads will see the appropriate value set on
  the object which is associated with the MQ Hobj value.
  
  ---------------------------------------------------------------
  The fix is targeted for delivery in the following PTFs:
  
  Version    Maintenance Level
  v9.1 LTS   9.1.0.20
  v9.2 LTS   9.2.0.20
  v9.3 LTS   9.3.0.10
  v9.x CD    9.3.2
  
  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

  IBM MQ BASE MP

• Fixed component ID

  5724H7271

Applicable component levels