Checkstyle error on Unix only - regex

Question

I'm using Ant to run a custom regex based checkstlye for */.html files. It's very simple config.
Ant build.xml:
<taskdef resource="checkstyletask.properties" classpath="checkstyle-5.5-all.jar"/>
<target name="check">
<checkstyle config="checks.xml" failOnViolation="false">
<fileset dir="${basedir}" includes="**/*.html"/>
<formatter type="plain"/>
<formatter type="xml" toFile="${basedir}/reports/checkstyle-report.xml"/>
</checkstyle>
</target>
checks.xml:
<module name="Checker">
<property name="charset" value="UTF-8"/>
<module name="RegexpMultiline">
<property name="format" value="\A.+<table>.+<\/table>.+\Z"/>
</module>
</module>
On Windows 7 64bit:
Apache Ant(TM) version 1.8.3 compiled on February 26 2012,
BUILD SUCCESSFUL
Total time: 1 second
On CentOS 64bit:
Apache Ant(TM) version 1.8.2 compiled on May 13 2011,
BUILD FAILED
build.xml:8: Unable to create a Checker: cannot initialize module RegexpMultiline - Unable to instantiate RegexpMultiline
Can anyone suggest something?
Thanks,

Answer 1

Ok, so simply running ant -v revealed the following:
parsing buildfile jar:file:/usr/share/java/ant-1.8.2.jar!/org/apache/tools/ant/antlib.xml with URI = jar:file:/usr/share/java/ant-1.8.2.jar!/org/apache/tools/ant/antlib.xml from a zip file
...
[checkstyle] checkstyle version 4.4
[checkstyle] compiled on Mon December 06 2010, 21:35 GMT
So the reason for the failure is not so much to do with the OS, as the version & configuration of the Ant installation.
I think what's happening is that the v4.4 checkstyle is being picked up from
/usr/share/java/ant-1.8.2.jar!/org/apache/tools/ant/antlib.xml
in preference to what is specified in build.xml:
<taskdef resource="checkstyletask.properties" classpath="${basedir}/checkstyle/checkstyle-5.5-all.jar"/>
Update:
I didn't find checkstyle.jar in /usr/share/ant/lib/, but there was one in /usr/share/java/
Not sure how Ant was picking that up, but this is what has finally fixed the issue:
yum remove checkstyle4.noarch
Now Ant is free to use the .jar from the project!
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