IZ44532: NULLPOINTEREXCEPTION OCCURS WHEN WEBSPHERE MQ JMS APPLICATIONS RECEIVE MESSAGES CONTAINING EXTRA ATTRIBUTES IN THE RFH2 FOLDER

WebSphere MQ V6.0 Fix Pack 6.0.2.7
WebSphere MQ V7.0 Fix Pack 7.0.1.1
WebSphere MQ V7.0 Fix Pack 7.0.1.2

APAR status

• Closed as program error.

Error description

• When using the WebSphere MQ Version 6 classes for Java Message
  Service (JMS), a NullPointerException occurs when a message is
  received. The exception contains a stack trace similar to one
  shown below:
  
  javax.jms.JMSException: MQJMS2002: failed to get message from
  MQ queue
  at com.ibm.mq.jms.services.ConfigEnvironment.
  newException(ConfigEnvironment.java:622)
  at com.ibm.mq.jms.MQMessageConsumer.
  getMessage(MQMessageConsumer.java:3827)
  at com.ibm.mq.jms.MQMessageConsumer.
  receiveInternal(MQMessageConsumer.java:2856)
  at com.ibm.mq.jms.MQMessageConsumer.
  receive(MQMessageConsumer.java:2648)
  
  As a result of the NullPointerException, the message that was
  being processed is returned to the queue it originally came
  from.
  

Local fix

• From the trace file we notice the data that is parsed has the
  following
  information:
  
  <mcd><Set context="none" dt="string">M6LGIQ8002001</Set><Fmt
  context="none" dt="string">XML1</Fmt><Type context="none"
  dt="string">WorkDayTrucks_20070406</Type><Msd context="none"
  dt="string">mrm</Msd></mcd>
  
  All the tags have additional attributed apart from the tag name.
  Tag
  Type
  has context="none" dt="string", similarly other tags have
  different data
  too.
  
  Currently, as per the WMQ JMS implementation, we do not expect
  any
  additional attributes to be present with the tags in the mcd
  folder.
  Depending on each of the tags in the Mcd folder a new Message
  object is
  instantiated.
  Because additional attributes are present with the tags we tend
  to
  ignore
  those tags and a Message object is never initialized and
  effectively a
  NPE is returned back to the application.
  
  we should modify the JMS layer not to have such strict parsing
  of tags
  but to allow tags with additional attributes too. Hence, this
  would need
  code changes to allow parsing of headers with additional
  attributes.
  

Problem summary

• ****************************************************************
  USERS AFFECTED:
  This issue affects users of the WebSphere MQ classes for JMS
  who have applications that receive messages sent from non-JMS
  applications that contain extra attributes in the Mcd folders
  of the RFH2 header.
  
  Platforms affected:
   All Distributed (iSeries, all Unix and Windows) +Java
  ****************************************************************
  PROBLEM SUMMARY:
  The code in the WebSphere MQ classes for JMS that parsed the
  Mcd folder in an RFH2 expected the tags of the sub-folder to
  be exact matches to only the folder names - that is, it
  expected the folders to be of the form:
  
  <Msd>value</Msd>
  <Type>value</Type>
  
  If additional data was added in the form of an attribute, such
  as:
  
  <Msd attribute="attValue">value</Msd>
  
  then the parsing failed, a NullPointerException was generated
  and the message was returned to the queue that it came from.
  

Problem conclusion

• The parsing code that previously used .equals() to recognize
  the sub-folders has been changed to use .startsWith(), so that
  further data could be ignored but not cause a match failure.
  
  This brings the Mcd parsing code into line with the code that
  parses other folders in the RFH2.
  
  ---------------------------------------------------------------
  The fix is targeted for delivery in the following PTFs:
  
                     v6.0
  Platform           Fix Pack 6.0.2.7
  --------           --------------------
  Windows            U200312
  AIX                U821719
  HP-UX (PA-RISC)    U821511
  HP-UX (Itanium)    U822328
  Solaris (SPARC)    U821514
  Solaris (x86-64)   U822359
  iSeries            tbc_p600_0_2_7
  Linux (x86)        U822325
  Linux (x86-64)     U822358
  Linux (zSeries)    U822329
  Linux (Power)      U822327
  Linux (s390x)      U822357
  
                     v7.0
  Platform           Fix Pack 7.0.1.0
  --------           --------------------
  Windows            U200306
  AIX                U823774
  HP-UX (PA-RISC)    U823665
  HP-UX (Itanium)    U823667
  Solaris (SPARC)    U823772
  Solaris (x86-64)   U824344
  iSeries            tbc_p700_0_1_0
  Linux (x86)        U823664
  Linux (x86-64)     U823773
  Linux (zSeries)    U823668
  Linux (Power)      U823666
  
  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 LIN X86 V6

• Fixed component ID

  5724H7204

Applicable component levels

• R600 PSY

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