IT11534: V8: JAVA APPLICATION TRIES TO GET A MESSAGE WITH A SPECIFIC MESSAGE ID AND GETS THE FIRST ONE ON THE QUEUE

APAR status

• Closed as program error.

Error description

• A Java application connects to a z/OS queue manager the BINDINGS
  transport, and calls MQQueue.get(MQMessage) requesting a message
  with a specific message identifier. Instead of the message that
  it requested, the application is actually given the first
  message on the queue.
  

Local fix

• n/a
  

Problem summary

• ****************************************************************
  USERS AFFECTED:
  This issue affects two categories of users:
  
  Category 1:
  -------------------
  Users of the IBM MQ V8 classes for Java who have applications
  which connect to an MQ for z/OS V800 queue manager using the
  BINDINGS transport and call either of the methods shown below:
  
  - MQQueue.get(MQMessage)
  - MQQueue.get(MQMessage, MQGetMessageOptions)
  
  to get a message with a specific message identifier, which is
  larger than 4kb, from a queue.
  
  Category 2:
  -------------------
  Users of the IBM MQ V8 classes for JMS who have applications
  which connect to an MQ for z/OS V800 queue manager using the
  BINDINGS transport, set a message selector for the property
  JMSMessageID to receive a specific message (which is larger than
  4kb) from a destination, and then call one of the following
  methods:
  
  - MessageConsumer.receive()
  - MessageConsumer.receive(long timeout)
  - MessageConsumer.receiveNoWait()
  
  
  Platforms affected:
  z/OS
  
  ****************************************************************
  PROBLEM DESCRIPTION:
  When a MQ classes for Java or classes for JMS application tried
  to get a message from a destination, where the message was
  larger than 4kb, the following sequence of events occurred:
  
  - The Java Message Queueing Interface (JMQI), used internally by
  the classes for Java and classes for JMS to communicate with a
  queue manager, issued an MQGET call using a 4kb buffer (the
  default buffer size used whenever either the classes for Java
  and classes for JMS try to get a message) , and the
  GetMessageOptions MQGMO_MATCH_MSG_ID and MQGMO_MATCH_CORREL_ID
  set.
  - As the message was larger than 4kb, the queue manager returned
  MQRC 2079 (MQRC_TRUNCATED_MSG_FAILED) back to the JMQI in
  response to the MQGET. The GetMessageOptions structure that the
  queue manager passed back to the JMQI contained a message token
  for that message, and the OriginalLength field in the MQMD that
  was passed back was set to the size of the message.
  - The JMQI then resized the internal buffer from 4kb to the size
  specified in the MQMD's OriginalLengh field, and then issued a
  second MQGET call. This MQGET call was made with the the new
  larger buffer and a GetMessageOptions structure that had the
  MQGMO_MATCH_MSG_TOKEN option set. However, the GetMessageOptions
  structure did not include the message token that was passed back
  from the queue manager.
  - The queue manager received the MQGET call that contained a
  GetMessageOptions structure which had the MQGMO_MATCH_MSG_TOKEN
  option set and no message token, and returned the first message
  on the queue.
  - The JMQI received the message returned by the queue manager
  and passed it back to the application.
  

Problem conclusion

• The JMQI (used by the MQ classes for Java and classes for JMS)
  has been updated to ensure that when the BINDINGS transport is
  being used and an MQGET operation completes, the output fields
  in the GetMessageOptions structure:
  
  - GroupStatus
  - MsgToken
  - ResolvedQName
  - ReturnedLength
  - Segmentation
  - SegmentStatus
  
  passed back by the queue manager are reused for any subsequent
  MQGET calls that need to be issued by the JMQI in order to get
  the message requested by the application.
  
  ---------------------------------------------------------------
  The fix is targeted for delivery in the following PTFs:
  
  Version    Maintenance Level
  v8.0       8.0.0.4
  
  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 BASE MULTIP

• Fixed component ID

  5724H7251

Applicable component levels

• R800 PSY

     UP