xml-xalan-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Santiago Pericas-Geertsen (JIRA)" <xalan-...@xml.apache.org>
Subject [jira] Commented: (XALANJ-2032) XSLTC: Multiple namespace prefixes produce unexpected prefixes in output
Date Tue, 08 Feb 2005 19:16:19 GMT
     [ http://issues.apache.org/jira/browse/XALANJ-2032?page=comments#action_58778 ]
     
Santiago Pericas-Geertsen commented on XALANJ-2032:
---------------------------------------------------

Yes, the report by Alfred is accurate and correct. The basic problem is qname equality. XSLTC
uses a hashtable for qname that effectively results in a "value" equality that ignores the
prefix. This can be problematic together with exclude-result-prefixes as shown in the example.


A possible workaround is to add the following XSLT instruction,

<xsl:namespace-alias stylesheet-prefix="xhtml" result-prefix="#default"/>

to ensure that a prefix alias is used.

Fixing this bug will require some re-engineering of the qname allocation mechanism in the
Parser.


> XSLTC: Multiple namespace prefixes produce unexpected prefixes in output
> ------------------------------------------------------------------------
>
>          Key: XALANJ-2032
>          URL: http://issues.apache.org/jira/browse/XALANJ-2032
>      Project: XalanJ2
>         Type: Bug
>   Components: XSLTC
>     Versions: 2.6
>     Reporter: Alfred Nathaniel
>     Assignee: Santiago Pericas-Geertsen

>
> The bug can be demonstrated with the following stylesheet:
> <?xml version="1.0"?>
> <!-- bug3.xsl -->
> <xsl:stylesheet
>   xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
>   xmlns:xhtml="http://www.w3.org/1999/xhtml"
>   xmlns="http://www.w3.org/1999/xhtml"
>   exclude-result-prefixes="xhtml"
>   version="1.0">
>   <xsl:template match="never">
>     <xhtml:br/>
>   </xsl:template>
>   <xsl:template match="/">
>     <html>
>       <body>
>         Hello<br/>world
>       </body>
>     </html>
>   </xsl:template>
> </xsl:stylesheet>
> Given any input the result produced by the Xalan interpreter is:
> xalan -in bug3.xsl -xsl bug3.xsl
> <html xmlns="http://www.w3.org/1999/xhtml">
>   <body>
>     Hello<br/>world
>   </body>
> </html>
> XSLTC 2.6.0 produces a different output:
> xalan -in in2.xml -xsl bug2.xsl -xsltc -v
> >>>>>>> Xalan Version Xalan Java 2.6.0, <<<<<<<
> <html xmlns="http://www.w3.org/1999/xhtml">
>   <body>
>     Hello<xhtml:br xmlns:xhtml="http://www.w3.org/1999/xhtml"/>world
>   </body>
> </html>
> As XML documents both versions are equivalent that one could argue it not really being
a bug. However, contemporary browsers (Explorer6.0, Firebox0.9.1, Mozilla1.7) ignore prefixed
HTML tags, that the use of XSLTC for HTML-to-HTML transformations is handicaped.
> The problem is in org.apache.xalan.xsltc.compiler.Parser. For each namespace there is
hashtable containing all tags in the stylesheet. In the example, <xhtml:br/> and <br/>
map to the same hashtable entry but the prefix form of the first one seen by the parser is
kept.
> The XSLTC code generator then uses this entry everywhere irrespective of the prefix form
used at the current position in the stylesheet. In order to avoid the pro blem, the hashtable
entries should be normalized to use a single prefix form.
> WORKAROUNDS
> The safest way to avoid the problem is to avoid using multiple prefixes for the same
namespace. Note that with an appropriate <xls:import> sequence also <xsl:template
match="xhtml:br"> without any literal <xhtml:br/> can lead to the same effect. That
means for XHTML-to-XHTML transformations that all literal tags in the stylesheet must use
the prefixed notation (<xhtml:html>).
> If that is too tedious for stylesheets containing a lot of literal HTML tags, you have
to rearrange the imports and template definitions that the parser sees for all tags the non-prefixed
form first. Otherwise we will have to filter the XSLTC output to do the prefix normalization
in a separate step.

-- 
This message is automatically generated by JIRA.
-
If you think it was sent incorrectly contact one of the administrators:
   http://issues.apache.org/jira/secure/Administrators.jspa
-
If you want more information on JIRA, or have a bug to report see:
   http://www.atlassian.com/software/jira


---------------------------------------------------------------------
To unsubscribe, e-mail: xalan-dev-unsubscribe@xml.apache.org
For additional commands, e-mail: xalan-dev-help@xml.apache.org


Mime
View raw message