PI60489: NULLPOINTEREXCEPTION CAN OCCUR WHEN GETTING A MESSAGE FROM A SHARED QUEUE ON A V800 Z/OS QMGR FROM A JMS CLIENT.

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• An NullPointerException can occur when getting
  a message from a shared queue on a V800 z/OS qmgr
  from a JMS client.
  The NPE is thrown because the WebSphere MQ classes
  for Java attempt to lookup a JmqiCodepage object
  (used to interpret bytes of data) with an invalid
  CCSID value (808464432).
  .
  From the WebSphere AppServer JMS trace,
  you can see the
  java.lang.NullPointerException being thrown from
  the method:
  .
    com.ibm.mq.jmqi.internal.JmqiDC.readString(...)
  .
  It is thrown because the WebSphere MQ classes for
  Java attempt to lookup a JmqiCodepage object
  (used to interpret bytes of data) with a CCSID
  value of 808464432:
  ..
  [22/03/16 14:36:37:278 CET] 0000001e DUMMY 3 (DUMMY)
  [:/76657665]
   DUMMY: JmqiCodepage.getJmqiCodepage(808464432):
   null(cached) <null>
  .
  
  This is not a valid CCSID value and, as such,
  a null JmqiCodepage object is returned.
  When attempting to use this null object,
  a Java NPE is thrown.
  .
  When a JMS message with GROUP ID is put to the
  shared queue, MQ then flattens the message data
  to be put to the CF Structure (Coupling Facility
  Structure). When the message is flattened, it results
  in a malformed message.
  .
  Additional Symptom(s) Search Keyword(s): MQMSGPROP/K
  .
  CWSJY0003W: JMSCC0110: An exception '
  Message : java.lang.NullPointerException
  Class : class java.lang.NullPointerException
  Stack : com.ibm.mq.jmqi.internal.JmqiDC.readString
            (JmqiDC.java:843)
  : com.ibm.mq.jmqi.MQRFH.readBodyFromBuffer
   (MQRFH.java:516)
  : com.ibm.msg.client.wmq.common.internal.messages.
    WMQReceiveMarshal.constructProviderMessageFromRFH2
    (WMQReceiveMarshal.java:300)
  : com.ibm.msg.client.wmq.common.internal.messages.
    WMQReceiveMarshal.constructProviderMessageFromProperties
    (WMQReceiveMarshal.java:191)
  : com.ibm.msg.client.wmq.common.internal.messages.
    WMQReceiveMarshal.createProviderMessage
    (WMQReceiveMarshal.java:467)
  : com.ibm.msg.client.wmq.common.internal.messages.
    WMQReceiveMarshal.exportProviderMessage
    (WMQReceiveMarshal.java:627)
  

Local fix

• Also this problem can be temporarily corrected
  by altering the queue being put to, to be
  PROPCTL(V6COMPAT), however this does reduce function
  and have other side effects are described in the
  knowledge center here :
  PROPCTL queue options
  https://ibm.biz/Bd4yMP
  or
  http://www.ibm.com/support/knowledgecenter/SSFKSJ_8.0.0/com.ibm.
  mq.mig.doc/q008230_.htm
  

Problem summary

• ****************************************************************
  * USERS AFFECTED: All users of WebSphere MQ for z/OS Version 8 *
  *                 Release 0 Modification 0.                    *
  ****************************************************************
  * PROBLEM DESCRIPTION: Putting a message to a shared queue,    *
  *                      containing message properties or RFH    *
  *                      data and values in MQMD Version 2       *
  *                      fields, such as groupId, results in     *
  *                      errors parsing the message when it is   *
  *                      later got due to incorrect header       *
  *                      chaining.                               *
  *                                                              *
  *                      This can result in a                    *
  *                      NullPointerException when a JMS client  *
  *                      does a get. Also if an affected message *
  *                      is moved or put to another queue, abend *
  *                      5C6-00D400B1 may be seen in the queue   *
  *                      manager.                                *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  When messages are put to the CF structure, if the level is less
  than or equal to CFLEVEL(4) or the message will be offloaded to
  DB2, the message will be flattened. During this processing,
  properties of the message are flattened into a RFH2 header, and
  MQMD V2 fields are extracted into a separate MQMDE, this is then
  stored in the CF structure (and DB2 if specified). However when
  the flattening occurs, the encoding field of the MQMDE being
  added is not correctly located. This results in the headers in
  the flatten message not being correct chained, with the format
  fields not correctly representing the following data.
  Additionally, in the cases where the message has a MQXQH when it
  is on a shared queue, the MQMDE will be returned in addition to
  a MQMD v2, with fields only being set in the MQMDE.
  
  When the a MQGET retrieves the message from the shared queue,
  the flattened message is reconstructed. However in this case,
  this may not occur correctly, and the headers will not be
  correctly chained, with the encoding, CCSID and format fields
  being correct for the data following. This results in the JMS
  client code raising a NullPointerException in
  com.ibm.mq.jmqi.internal.JmqiDC.readString(), when the code
  looks for the codepage based on the CCSID.
  

Problem conclusion

• The flatten processing in this case has been corrected, to
  correctly locate the encoding field of the MQMDE, resulting in
  the correct chaining of the headers in the message when stored
  on the CF. This results in the valid message being returned
  during a MQGET.
  
  MQMSGPROP/K
  000Y
  CSQMPRPF
  

Temporary fix

• *********
  * HIPER *
  *********
  

Comments

APAR Information

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

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

  UI37277

Modules/Macros

•    CSQMPRPF
  

Fix information

• Fixed component name

  WMQ Z/OS 8

• Fixed component ID

  5655W9700

Applicable component levels

• R000 PSY UI37277

     UP16/05/26 P F605 Ž

Fix is available

• Select the PTF appropriate for your component level. You will be required to sign in. Distribution on physical media is not available in all countries.