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
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)
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.
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_DIRrun 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 :
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/.
Note : the css-validator.jar file must be located at the exact same level as the lib/ folder to work properly.