[XALANJ-2347] xpath expression containing attribute test followed by or and the preceding axis causes stack overflow.

• Type: Bug
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Affects Version/s: 2.7
• Component/s: Xalan
• Environment: Win XP, Xalan Java 2.7.0, java.version=1.5.0_06
• Xalan info: PatchAvailable
• Assignee: Henry Zongaro
• Reporter: Robert Eaton
• Created: 29/Nov/06 10:08
• Updated: 19/Dec/06 14:57

Description

I have been getting a StackOverflowError when trying to perform an XSL transformation using Xalan 2.7.0 with a styleshhet I had written. I have simplified the the XSL and the problem seems to be related to an xpath expression used in an if, but I can't see anything wrong with it.
I was using this xml:

<?xml version="1.0" encoding="UTF-8"?>
<docdef>
<region name="Main Region">
<section id="2" name="section1">
<frag id="1" name="part1" type="text">
<p style="body" align="left" xml:space="preserve">first paragraph.</p>
</frag>
<frag id="2" name="next fragment" type="text">
<p style="inherit" align="center" xml:space="preserve">Paragraph with a style of inherit but its own alignment , first in fragment.</p>
<p style="inherit" xml:space="preserve"/>
<p xml:space="preserve">Another paragraph</p>
</frag>
</section>
</region>
</docdef>

with this xsl:
<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns:fo="http://www.w3.org/1999/XSL/Format" xmlns:w="http://schemas.microsoft.com/office/word/2003/wordml" xmlns:aml="http://schemas.microsoft.com/aml/2001/core" xmlns:w10="urn:schemas-microsoft-com:office:word" xmlns:v="urn:schemas-microsoft-com:vml" xmlns:wx="http://schemas.microsoft.com/office/word/2003/auxHint" xmlns:o="urn:schemas-microsoft-com:office:office" >
<xsl:template match="p[@style='inherit']">
<xsl:if test="not(preceding-sibling::) or preceding-sibling::[1] != preceding-sibling:[1]">
<w>
<w:pPr>
<!-- This is the problem statement. The error does not occur if the '@align or' is removed from the start of the xpath.-->
<xsl:if test="@align or preceding:[not(ancestor::table)][not(@style='inherit')][1]/@align">
<xsl:element name="w:jc">
<xsl:if test="@align">
<xsl:attribute name="w:val"><xsl:value-of select="@align"/></xsl:attribute>
</xsl:if>
<xsl:if test="not(@align)">
<xsl:attribute name="w:val">
<xsl:value-of select="preceding:[not(ancestor::table)][not(@style='inherit')][1]/@align"/>
</xsl:attribute>
</xsl:if>
</xsl:element>
</xsl:if>
</w:pPr>
<xsl:apply-templates/>
</w>
</xsl:if>
</xsl:template>
</xsl:stylesheet>

The error message I get from Xalan is
(Location of error unknown)XSLT Error (java.lang.StackOverflowError): null
Exception in thread "main" java.lang.RuntimeException
at org.apache.xalan.xslt.Process.doExit(Process.java:1153)
at org.apache.xalan.xslt.Process.main(Process.java:1126)

If I do the transformation within XMLSpy it does not report any errors so it seems to be something to do with Xalan.

I have tried enabling various tracing options, see output below, but I get no additional output.

C:\xalan\xalan-j_2_7_0>java -Xmx128M -cp c:\xalan\xalan-j_2_7_0\xalan.jar;c:\xal
an\xalan-j_2_7_0\xml-apis.jar;c:\xalan\xalan-j_2_7_0\xercesImpl.jar org.apache.x
alan.xslt.Process -TT -in test.xml -xsl test.xsl -out out.xml

(Location of error unknown)XSLT Error (java.lang.StackOverflowError): null
Exception in thread "main" java.lang.RuntimeException
at org.apache.xalan.xslt.Process.doExit(Process.java:1153)
at org.apache.xalan.xslt.Process.main(Process.java:1126)

I also tried -TG, -TS and -TTC and all give the same result as above.
The results of running environement check are shown below.

1. • • • • BEGIN writeEnvironmentReport($Revision: 1.29 $): Useful stuff found: ----
           version.DOM.draftlevel=2.0fd
           java.class.path=c:\xalan\xalan-j_2_7_0\xalan.jar;c:\xalan\xalan-j_2_7_0\xml-apis.jar;c:\xalan\xalan-j_2_7_0\xercesImpl.jar
           version.JAXP=1.1 or higher
           java.ext.dirs=C:\Program Files\Java\jre1.5.0_06\lib\ext
           version.xerces2=Xerces-J 2.7.1
           version.xerces1=not-present
           version.xalan2_2=Xalan Java 2.7.0
           version.xalan1=not-present
           version.ant=not-present
           java.version=1.5.0_06
           version.DOM=2.0
           version.crimson=not-present
           sun.boot.class.path=C:\Program Files\Java\jre1.5.0_06\lib\rt.jar;C:\Program Files\Java\jre1.5.0_06\lib\i18n.jar;C:\Program Files\Java\jre1.5.0_06\lib\sunrsasign.jar;C:\Program Files\Java\jre1.5.0_06\lib\jsse.jar;C:\Program Files\Java\jre1.5.0_06\lib\jce.jar;C:\Program Files\Java\jre1.5.0_06\lib\charsets.jar;C:\Program Files\Java\jre1.5.0_06\classes
         • BEGIN Listing XML-related jars in: foundclasses.java.class.path ----
           xalan.jar-path=c:\xalan\xalan-j_2_7_0\xalan.jar
           xml-apis.jar-apparent.version=xml-apis.jar from head branch of xml-commons, tag: xml-commons-external_1_3_02
           xml-apis.jar-path=c:\xalan\xalan-j_2_7_0\xml-apis.jar
           xercesImpl.jar-apparent.version=xercesImpl.jar from Xerces-J-bin.2.7.1
           xercesImpl.jar-path=c:\xalan\xalan-j_2_7_0\xercesImpl.jar
           • END Listing XML-related jars in: foundclasses.java.class.path -----
             version.SAX=2.0
             version.xalan2x=Xalan Java 2.7.0
           • END writeEnvironmentReport: Useful properties found: -----
2. YAHOO! Your environment seems to be OK.

I have also managed to get the error with a different but similar Xpath expression. It seems to be a problem when it starts with "@align or preceding" an attribute test followed by the ancestor axis does not seem to cause a problem and if I remove the '@align or' from the begining and break it up into multiple xsl:if statements it is okay.
I believe it is happening when the stylesheet it first passed before it actually starts the transformation.

Issue Links

• relates to: XALANJ-1880 StackOverflowError on XPath expression