Download and Install the CSS Validator
CSS Validation Service
Check Cascading Style Sheets (CSS) and (X)HTML documents with style sheets
Download and Install the CSS Validator
Download the CSS Validator
The CSS validator is available in three different packaging: from Git for developers who want the very latest version,
as a jar archive to build applications and for use as a command line tool, and (since 2009) as a war archive for server-side
applications.
Download the source code
The
source of the CSS Validator
can be retrieved with Git.
Please note that the online service for the CSS validator is a stable release,
generally a little older than the version under Git, and their results and behaviour may differ.
Download the Java archive (jar)
css-validator.jar
Installation Guide
The CSS Validation service is based on a servlet written in the cross-platform Java language, and can
be installed on any servlet platform. While the official service from W3C runs under the Jigsaw server
(which is the recommended setup), we will for the sake of convenience describe in this guide the setup
under Apache's servlet engine, Tomcat, as well as some quick instructions for Jigsaw and commandline usage.
Prerequisites
This guide assumes that you have already downloaded and installed successfully the following:
a working java environment ;
the
Ant
java build tool ;
a Java servlet container such as
Jigsaw
Tomcat
or
Jetty
, if you plan to provide the validator as a web service.
As a prerequisite to the installation, you will need to know the complete path to the java library called
servlet.jar
It is generally available within
TOMCAT_DIR
]/common/lib/
, with
TOMCAT_DIR
being the path under which Tomcat is installed. It may also be found under the name servlet-api.jar. If you can not
find it,
java.sun.com
will have it.
Installation of the CSS validator under Tomcat
Download the Git source as explained
above
Edit the file called
VALIDATOR_DIR
]build.xml
and replace the value of
property servlet.lib with the full path to
servlet.jar
You can now build the source : from
VALIDATOR_DIR
run the command
ant war
Running ant should download a number of necessary libraries, and build the archive called
css-validator.war
Copy or move
css-validator.war
to
TOMCAT_DIR
]/webapps
Finally, restart the Tomcat engine :
"cd
TOMCAT_DIR
./bin/
shutdown.sh
./bin/
startup.sh
;"
Installation of the CSS validator under Jigsaw
Download the Git source as explained previously, save it under
JIGSAW_DIR
]/WWW
and build source with
ant jigsaw
Next, configure the root folder for the validator (in most cases it will be called css-validator) to make it a servlet container.
Within your Jigsaw installation, launch the Jigsaw Admin utility, browse to
css-validator
and change it from HTTPFrame to ServletDirectoryFrame ;
The next step will be to create a "validator" resource as 'ServletWrapper' class. A 'ServletWrapperFrame' frame will automagically
be created for it. You will need to provide the name of the servlet class, which for the CSS Validator os org.w3c.css.servlet.CssValidator.
Note that a file called “validator” may already be present – you MUST rename it, as the validator absolutely needs to enforce this name for the servlet wrapper ;
Make sure that all the .jar libraries within the
JIGSAW_DIR
]/WWW/css-validator/lib
folder
are properly added to Jigsaw's CLASSPATH setup.
Finally, restart Jigsaw and point your browser to the validator. The URI should be something like :
Command-Line use
Any computer with Java installed can also run the validator from the terminal/console as a commandline tool.
Download the css-validator.jar jar archive (or build it with
ant jar
) and run it as :
java -jar css-validator.jar http://www.w3.org/
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