[xsl] Saxon custom extensions problem

["Gustaf Liljegren" <gustaf dot liljegren at xml dot se>]

Finally upgraded to Saxon 6.4.3. :-)

Now I have some questions on the documentation for custom extensions to
Saxon, namely the extensibility.html document:

 'With the short-cut technique, the URI for the namespace identifies
  the class where the external function will be found. The namespace
  URI must either be "java:" followed by the fully-qualified class
  name (for example xmlns:date="java:java.util.Date"), [...] The class
  must be on the classpath.'

Okay, here's my custom Java extension function:

class ReverseString {
  public static String reverseIt(String source) {
    int i, len = source.length();
    StringBuffer dest = new StringBuffer(len);
    for (i = (len - 1); i >= 0; i--) {
      dest.append(source.charAt(i));
    }
    return dest.toString();
  }
}

I can take Java syntax, but I'm not so familiar with terminology like
"fully-qualified class name". I have no class library, just a single
function, and in the same directory as the stylesheet. So if I want to use
it as an extension for an FO transformation, I guess I should write:

<?xml version="1.0" encoding="iso-8859-1"?>
<xsl:stylesheet version="1.0"
  xmlns:xsl="http://www.w3.org/1999/XSL/Transform";
  xmlns:fo="http://www.w3.org/1999/XSL/Format";
  xmlns:my="java:ReverseString">

And later on, I use it like this:

<xsl:value-of select="my:reverseIt(.)"/>

Something is clearly wrong, and it seems to happen at the namespace
declaration already:

  The URI java:ReverseString does not identify an external Java class
Transformation failed: run-time errors were reported

For the future, it would be helpful to include two tiny (but complete)
examples in the documentation: one for importing, and another for exporting
content from the stylesheet to a Java application.

Gustaf Liljegren



 XSL-List info and archive:  http://www.mulberrytech.com/xsl/xsl-list