 
Quickly generate XSLT stylesheets with Asami Tomoharu's Relaxer. Relaxer (http://www.relaxer.org) is a Java schema compiler for XML. Relaxer can generate Java classes [Hack #99] based on RELAX NG, DTDs, XML Schema, and RELAX Core schemas (http://www.xml.gr.jp/relax/). It can also generate schemas (see [Hack #73], [Hack #74], and [Hack #75] ) from one or more XML documents. There are many other things Relaxer can do, but in this hack I want to focus on its ability to generate XSLT stylesheets based on one or more XML documents. Generating a stylesheet with Relaxer can give you a start for designing your own stylesheets. It's quite easy to use and merits some of our attention. You can download Version 1.0 of Relaxer (relaxer-1.0.zip) from http://www.relaxer.org/download/index.html. After downloading the file, you can run the installation script by typing this line, assuming of course that you have Java on your system: java -jar relaxer-1.0.zip
The script will ask you where you want to install Relaxer: Install directory [default: C:\usr\local\lib\relaxer]: c:\lib Command directory [default: C:\usr\local\bin]: c:\bin
If you are on Windows and submitted c:\lib and c:\bin, for example, the script will respond: [Configuration] Install directory = c:\lib Command directory = c:\bin Type "yes" to install, "no" to re-enter, "exit" to exit >
Use whatever directories are appropriate for your system. If you type yes here, you will see this report: Extract archives... Generate script... script = c:\bin\relaxer.bat script = c:\bin\relaxer Done.
Now check the Relaxer version: relaxer -version
This should yield: Copyright(c) 2000-2003 ASAMI,Tomoharu. All rights reserved. Relaxer Version 1.0 (20031224) by asami@relaxer.org
Now you're ready to generate an XSLT stylesheet with Relaxer. You'll use a file called gen.xml, which is identical to time.xml (Example 3-11). Example 3-11. gen.xml <?xml version="1.0" encoding="UTF-8"?> <!-- a time instant --> <time timezone="PST"> <hour>11</hour> <minute>59</minute> <second>59</second> <meridiem>p.m.</meridiem> <atomic signal="true"/> </time>
Use the -xslt switch to generate the stylesheet, and the -verbose switch to see what Relaxer's doing during processing time: relaxer -verbose -xslt gen.xml
You should see this: Copyright(c) 2000-2003 ASAMI,Tomoharu. All rights reserved. Relaxer Version 1.0 (20031224) by asami@relaxer.org Source file : file:/C:/Hacks/examples/gen.xml artifact = gen.xsl
Relaxer generated the artifact gen.xsl. It's a simple stylesheet that mirrors gen.xml and can perform an identity transform on gen.xml (Example 3-12). Example 3-12. gen.xsl <?xml version='1.0'?> <xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform"> <xsl:output indent="yes" method="xml"/> <xsl:template match="minute"> <minute> <xsl:apply-templates/> </minute> </xsl:template> <xsl:template match="atomic"> <atomic> <xsl:attribute name="signal"> <xsl:value-of select="@signal"/> </xsl:attribute> <xsl:apply-templates/> </atomic> </xsl:template> <xsl:template match="meridiem"> <meridiem> <xsl:apply-templates/> </meridiem> </xsl:template> <xsl:template match="second"> <second> <xsl:apply-templates/> </second> </xsl:template> <xsl:template match="time[hour and minute and second and meridiem and atomic]"> <time> <xsl:attribute name="timezone"> <xsl:value-of select="@timezone"/> </xsl:attribute> <xsl:apply-templates/> </time> </xsl:template> <xsl:template match="hour"> <hour> <xsl:apply-templates/> </hour> </xsl:template> </xsl:stylesheet>
Apply this stylesheet to gen.xml: xalan gen.xml gen.xsl
and you'll get a close copy of the original: <?xml version="1.0" encoding="UTF-8"?> <time timezone="PST"> <hour>11</hour> <minute>59</minute> <second>59</second> <meridiem>p.m.</meridiem> <atomic signal="true"/> </time>
Generating stylesheets is quick and easy to do with Relaxer. It will provide you with a ready-made stylesheet that you can then edit for your own purposes. You could also use Relaxer to programmatically generate a series of stylesheets based on one or more instance documents. | 