PM11936: A NULL ERROR MESSAGE MAY BE REPORTED IF A CASE IN AN XQUERY TYPESWITCH EXPRESSION CONSISTS OF A REFERENCE TO A VARIABLE

APAR status

• Closed as program error.

Error description

• If one of the cases in an XQuery typeswitch expression
  consists of just a reference to a variable, a null error
  message might be reported, and the query will not be
  evaluated.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED:  All users of IBM WebSphere Application      *
  *                  Server v7.0 Feature Pack for XML 1.0.       *
  ****************************************************************
  * PROBLEM DESCRIPTION: A null error message is reported if     *
  *                      one of the case clauses of an XQuery    *
  *                      typeswitch expression contains just a   *
  *                      reference to a variable.                *
  ****************************************************************
  * RECOMMENDATION:  Install a fix pack that contains this APAR. *
  ****************************************************************
  As the XQuery processor translates an XQuery expression from
  its syntax tree representation into the representation that it
  will use to actually evaluate the expression, it performs some
  analysis to estimate the type of value that will be returned
  by each subexpression.  In some instances, the processor
  cannot determine a precise type, so it represents the type
  using a null reference.
  
  In the case of a typeswitch expression, the processor checks
  the type of the value produced by each clause of the
  typeswitch, in order to determine what the type of the result
  of the entire typeswitch expression might be.  However, this
  analysis of the typeswitch expression failed to take into
  account that the type of one of its clause expressions might
  be a null reference, which resulted in NullPointerException in
  the processor.  That was ultimately reported as a null error
  message to the user.
  

Problem conclusion

• The problem was fixed by having the XQuery processor check
  whether the type of any clause of the typeswitch is a null
  reference.  If it is, the processor will use null as the
  estimated type of the typeswitch as a whole - indicating that a
  precise type cannot be determined during the translation - and
  processing continues as normal.
  
  The fix for this APAR is currently targeted for inclusion in
  fix pack 1.0.0.7. Please refer to the Recommended Updates
  page for delivery information:
  http://www.ibm.com/support/docview.wss?rs=180&uid=swg27004980
  

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

  XML FEATUREPACK

• Fixed component ID

  5724J0856

Applicable component levels

• R700 PSY

     UP