IT45625: JMQI does not replace unmappable characters in the message body when indicated to do so.

APAR status

• Closed as program error.

Error description

• When an MQ Classes for Java or MQ Classes for JMS (JMQI)
  application receives a message body encoded in one CCSID but a
  different CCSID is defined in the message header (malformed),
  and the unmappable character system properties are set, the
  message is not decoded as expected.
  

Local fix

Problem summary

• ****************************************************************
  USERS AFFECTED:
  Users of JMQI reliant applications (MQ Classes for Java and MQ
  Classes for JMS) which are processing malformed messages with
  the following JVM system properties defined.
  
  -Dcom.ibm.mq.cfg.jmqi.UnmappableCharacterAction=REPLACE
  -Dcom.ibm.mq.cfg.jmqi.UnmappableCharacterReplacement=<Base-10
  character>
  
  Further details of these system properties can be found in the
  official documentation -
  https://www.ibm.com/docs/en/ibm-mq/latest?topic=messaging-charac
  ter-string-conversions-in-mq-classes-jms
  
  
  Platforms affected:
  MultiPlatform
  
  ****************************************************************
  PROBLEM DESCRIPTION:
  When an MQ Classes for Java or MQ Classes for JMS (JMQI)
  application receives a message body encoded in one CCSID, but a
  different CCSID is defined in the message header (malformed),
  then the message body is not decoded as expected, regardless of
  whether the following JVM system properties are set.
  
  -Dcom.ibm.mq.cfg.jmqi.UnmappableCharacterAction=REPLACE
  -Dcom.ibm.mq.cfg.jmqi.UnmappableCharacterReplacement=<Base-10
  character>
  
  ----
  
  For the below explanation accept that, at the time of this APAR
  being published, CCSID 819 is synonymous with ISO-8859-1 and
  CCSID 1208 is synonymous with UTF-8 encoding. Note these
  specific CCSID's are used here for example only - this APAR can
  apply to any combination of supported CCSIDs.
  
  Consider the following scenario when processing a malformed
  message with the following JVM system properties explicitly set.
  
  -Dcom.ibm.mq.cfg.jmqi.UnmappableCharacterAction=REPLACE
  -Dcom.ibm.mq.cfg.jmqi.UnmappableCharacterReplacement=63
  
  1) A message is received (MQGET) with the body encoded in CCSID
  819, containing the byte 0xE9 (for example), and the message
  headers specify CCSID 1208.
  2) The JMQI will attempt to decode 0xE9 into the "question mark"
  character (63 in base-10, 0x3F in base-16) since it is outside
  the supported encoding of CCSID 1208.
  3) The JMQI will now erroneously (since the JVM system
  properties are set) replace 0xE9 with 0xEFBFBD (not 0x3F), which
  is the CCSID 1208 default replacement character.
  
  The JMQI did not honour the values defined in the JVM system
  properties and therefore failed to replace the unsupported
  characters in the manner expected by the user of the
  application.
  

Problem conclusion

• The JMQI will now correctly honour the following JVM system
  property values when processing a malformed message.
  
  -Dcom.ibm.mq.cfg.jmqi.UnmappableCharacterAction=REPLACE
  -Dcom.ibm.mq.cfg.jmqi.UnmappableCharacterReplacement=<Base-10
  character>
  
  Please note that the behaviour of processing malformed messages
  is in itself not recommended and, where possible, efforts should
  be made to correct this.
  
  ---------------------------------------------------------------
  The fix is targeted for delivery in the following PTFs:
  
  Version    Maintenance Level
  v9.2 LTS   9.2.0.30
  v9.3 LTS   9.3.0.20
  v9.4 LTS   9.4.0.0
  
  The latest available maintenance can be obtained from
  'IBM MQ Recommended Fixes'
  https://www.ibm.com/support/pages/recommended-fixes-ibm-mq
  
  If the maintenance level is not yet available information on
  its planned availability can be found in 'IBM MQ
  Planned Maintenance Release Dates'
  https://ibm.biz/mqplannedmaintenance
  
  ---------------------------------------------------------------
  

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

  MQ BASE V9.2

• Fixed component ID

  5724H7281

Applicable component levels