July 2004
Intermediate to advanced
479 pages
12h 30m
English
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
Create a DTD from an Instance
If you need a DTD in a hurry, create it from an XML instance using Trang, Relaxer, DTDGenerator, or xmlspy.
Several free Java tools are available that can generate a DTD based on an XML instance or instances. James Clark’s Trang (http://www.thaiopensource.com/relaxng/trang.html) can, among other things, convert an XML document to a DTD, as can Relaxer (http://www.relaxer.org). Michael Kay’s DTDGenerator (http://saxon.sourceforge.net/dtdgen.html), once part of the Saxon project, consists of a single Java class that is dedicated to XML-to-DTD conversion. This hack walks you through the steps to generate a DTD from a simple instance using each of these tools.
Trang
You can download the current Trang JAR (trang.jar) from http://www.thaiopensource.com/download/, then place the JAR in the working directory. The Trang archive comes with a manual (trang-manual.html) that provides details on how to use Trang. I will cover only what is needed to create a DTD in this section. (If you need help with Java, refer to [Hack #10] .)
To create a DTD from time.xml, run this command:
java -jar trang.jar -I xml -O dtd time.xml generated.dtd
The -I switch indicates the type of input (XML),
and -O indicates the type of output (DTD).
time.xml is the input file and
generated.dtd is the output file. You could
simplify this command by skipping the -I and
-O options, which will produce the same result:
java -jar trang.jar time.xml generated.dtd
The file generated.dtd looks like ...
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.