Display property set to none in groups which are referred by use elements causes exceptions

[Helder Magalhães <he...@gmail.com>]

An apparently new issue was isolated. I've searched open bugs [1] and
wasn't able to find any known related issue, therefore I'd appreciate
feedback prior to creating a new bug report [2]. Specifically, I'm not
sure if the appropriate component is "SVG DOM" and if the issue is
Platform/OS-specific. Although it was isolated in Windows XP SP2, I
believe it's located in Batik-specific code and therefore will
reproduce in any supported Platform/OS.


Product:
Batik


Component:
SVG DOM


Summary:
Display property set to none in groups which are referred by use
elements causes exceptions.


Description:
Setting display property to none in groups which are «used» as symbols
raises an exception.

Two separate cases, issuing different exceptions, were reduced
although they're most probably related to each other:
 * Case "use-group-display-none.svg" - if display property is set to
"none", a "java.lang.IllegalArgumentException" is raised;
 * Case "use-group-display-none-toggle.svg" - toggling container's
display property twice will raise "java.lang.NullPointerException".

Symptoms were observed in (release) versions 1.6 and 1.7 and in recent
nightly build [3] (1.8pre+r614190). Version 1.6 shows a different
exception (java.net.MalformedURLException) in case
"use-group-display-none-toggle.svg", but I believe the exception is
hiding the real issue.


Workaround:
Possible workarounds exist, although the behavior may become different
from the initially expected:
 * Case "use-group-display-none.svg" - setting display property to
"none" in use element avoids the exception;
 * Case "use-group-display-none-toggle.svg" - removing display
property from "symbol" will avoid the exception.


Keywords:
use group display none


Regards,

  Helder Magalhães


[1] http://issues.apache.org/bugzilla/buglist.cgi?query_format=specific&bug_status=__open__&product=Batik
[2] http://issues.apache.org/bugzilla/enter_bug.cgi?product=Batik
[3] http://arc.mcc.id.au/batik-nightly/
--
Helder Magalhães
helder.magalhaes@gmail.com