Saxon in Java: XSLT for CSV to XML

Question

Mostly continued from this question: XSLT: CSV (or Flat File, or Plain Text) to XML

So, I have an XSLT from here: http://andrewjwelch.com/code/xslt/csv/csv-to-xml_v2.html

And it converts a CSV file to an XML document. It does this when used with the following command on the command line:

java -jar saxon9he.jar -xsl:csv-to-xml.csv -it:main -o:output.xml

So now the question becomes: How do I do I do this in my Java code?

Right now I have code that looks like this:

TransformerFactory transformerFactory = TransformerFactory.newInstance();
StreamSource xsltSource = new StreamSource(new File("location/of/csv-to-xml.xsl"));
Transformer transformer = transformerFactory.newTransformer(xsltSource);
StringWriter stringWriter = new StringWriter();
transformer.transform(documentSource, new StreamResult(stringWriter));
String transformedDocument = stringWriter.toString().trim();

(The Transformer is an instance of net.sf.saxon.Controller.)

The trick on the command line is to specify "-it:main" to point right at the named template in the XSLT. This means you don't have to provide the source file with the "-s" flag.

The problem starts again on the Java side. Where/how would I specify this "-it:main"? Wouldn't doing so break other XSLT's that don't need that specified? Would I have to name every template in every XSLT file "main?" Given the method signature of Transformer.transform(), I have to specify the source file, so doesn't that defeat all the progress I've made in figuring this thing out?

Edit: I found the s9api hidden inside the saxon9he.jar, if anyone is looking for it.

Answer 1

You are using the JAXP API, which was designed for XSLT 1.0. If you want to make use of XSLT 2.0 features, like the ability to start a transformation at a named template, I would recommend using the s9api interface instead, which is much better designed for this purpose.

However, if you've got a lot of existing JAXP code and you don't want to rewrite it, you can usually achieve what you want by downcasting the JAXP objects to the underlying Saxon implementation classes. For example, you can cast the JAXP Transformer as net.sf.saxon.Controller, and that gives you access to controller.setInitialTemplate(); when it comes to calling the transform() method, just supply null as the Source parameter.

Incidentally, if you're writing code that requires a 2.0 processor then I wouldn't use TransformerFactory.newInstance(), which will give you any old XSLT processor that it finds on the classpath. Use new net.sf.saxon.TransformerFactoryImpl() instead, which (a) is more robust, and (b) much much faster.