XOM API for Processing XML with Java

[Thomas LEDUC <thomas.leduc AT cerma.archi.fr>]

Dear list-members,

I would like to benefit from XOM recursive XInclude ability. That's why,
I've given XALAN up. With XALAN, I was able to combine a (single)
XInclude with an EntityResolver (the x-included XML was located in the
JAR file and activated as a ResourceStream trough an EntityResolver) and
a XSLT Transform.

What I want right now is tu use XOM so as to combine 2 or 3 levels of
recursive XInclude with an EntityResolver (so as to x-include the XML
located as resources in the JAR file) and a XSLT transform. To achieve
such an objective, I've tried to follow P. Taylor's intructions (thanks
to him) described in the following post :
    https://lists.ibiblio.org/sympa/arc/xom-interest/2009-August/003977.html

To reproduce the process I want to do, I've developed the small use case
presented below. Unfortunately, the following independent class (that
replaces class.getResourceAsStream by ByteArrayInputStream : XML2 is
x-included in XML1) compiles but crashes during execution. Do you know
why ? What should I do to solve my bug ?

Many thanks for your help,

import java.io.*;
import javax.xml.parsers.SAXParserFactory;
import nu.xom.*;
import nu.xom.xinclude.XIncluder;
import nu.xom.xslt.XSLTransform;
import org.xml.sax.*;

public class MyXomTest {
    private static final String XML1 = "<?xml version='1.0'><aa
xmlns:xi='http://www.w3.org/2001/XInclude'><xi:include
href='foo.xml'/><dd/></aa>";
    private static final String XML2 = "<?xml version='1.0'?><bb><cc
name='foo'/></bb>";
    private static final String XSLT_IDENTITY = "<?xml version='1.0'?>"
            + "<xsl:stylesheet version='1.0'
xmlns:xsl=\"http://www.w3.org/1999/XSL/Transform\";>"
            + "<xsl:template match='node()|@*'>" + "<xsl:copy>"
            + "<xsl:apply-templates select='@*|node()'/>" + "</xsl:copy>"
            + "</xsl:template>" + "</xsl:stylesheet>";

    public static class MyEntityResolver implements EntityResolver {
        @Override
        public InputSource resolveEntity(String arg0, String arg1)
                throws SAXException, IOException {
            InputStream inputStream = new
ByteArrayInputStream(XML2.getBytes());
            InputSource inputSource = new InputSource(inputStream);
            inputSource.setSystemId(AConsoleCommand.USER_DIR);
            return inputSource;
        }
    }

    public static void main(String[] args) throws Exception {
        SAXParserFactory saxParserFactory = SAXParserFactory.newInstance();
        saxParserFactory.setNamespaceAware(true);
        saxParserFactory.setXIncludeAware(true);
        XMLReader x = saxParserFactory.newSAXParser().getXMLReader();
        x.setEntityResolver(new MyEntityResolver());

        Builder builder = new Builder(x);
        Document input = builder
                .build(new ByteArrayInputStream(XML1.getBytes()));
        Document intermed_result = XIncluder.resolve(input, builder);
        Document stylesheet = builder.build(new ByteArrayInputStream(
                XSLT_IDENTITY.getBytes()));
        XSLTransform transform = new XSLTransform(stylesheet);
        Nodes output = transform.transform(intermed_result);
        Document result = XSLTransform.toDocument(output);
        System.out.println(result.toXML());
    }
}