问Xalan-J:在扩展函数中解析QName文本值的名称空间

EN

DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
factory.setNamespaceAware(true);
DocumentBuilder builder = factory.newDocumentBuilder();
Document parse = builder.parse(new InputSource(new StringReader(document)));
transformer.transform(new DOMSource(parse), new StreamResult(writer));

package org.stackoverflow.example;

import java.io.*;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.transform.*;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.*;
import org.apache.xalan.extensions.ExpressionContext;
import org.w3c.dom.Document;
import org.w3c.dom.NamedNodeMap;
import org.w3c.dom.Node;
import org.w3c.dom.traversal.NodeIterator;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;

public class XPathFunctionQNameTextValueResolver {
    
    public static final boolean resolveQNameTextValue(ExpressionContext ctx, NodeIterator nodes) {        
        Node node = nodes.nextNode();
        while (node != null) {
            if (node.hasChildNodes()) {
                String textValue = node.getFirstChild().getNodeValue();
                String[] pfxAndName = textValue.split(":");
                String prefix = "";
                String name = textValue;
                if (pfxAndName.length == 2) {
                    prefix = pfxAndName[0];
                    name = pfxAndName[1];
                }
                String namespace = node.lookupNamespaceURI(prefix);
                // "namespace" is always null, unless null is supplied as "prefix", which returns the default namespace
                NamedNodeMap attributes = node.getAttributes();
                if (attributes != null) {
                    // "attributes" does not contain any "xmlns" attributes
                }
                System.out.println(
                        String.format(
                                "namespace: %s, prefix:%s, local-name: %s, attributes-len: %d", 
                                namespace, prefix, name, attributes != null ? attributes.getLength() : 0));
            }
            node = nodes.nextNode();
        }
        
        return false;
    }
    
    public static void main(String[] args) throws TransformerConfigurationException, TransformerException, ParserConfigurationException, IOException, SAXException {
        String xslt = "" +
"<xsl:stylesheet xmlns:xsl='http://www.w3.org/1999/XSL/Transform'\n" +
"                xmlns:sofun='xalan://org.stackoverflow.example.XPathFunctionQNameTextValueResolver'\n" +
"               xmlns:doc='org.stackoverflow.example.document'>\n" +
"   <xsl:template match='/doc:document/doc:element'>\n" +
"       <xsl:value-of select='sofun:resolveQNameTextValue(.)' />\n" +
"   </xsl:template>\n" +
"</xsl:stylesheet>";
        String document = "" +
"<document xmlns='org.stackoverflow.example.document'>\n" +
"   <element xmlns:value=\"org.stackoverflow.example.value\">value:some-value</element>\n" +
"</document>";
        
        TransformerFactory xalanTransFact = new org.apache.xalan.processor.TransformerFactoryImpl();
        Templates template = xalanTransFact.newTemplates(new StreamSource(new StringReader(xslt)));
        
        StringWriter writer = new StringWriter();
        Transformer transformer = template.newTransformer();
        
        DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
        factory.setNamespaceAware(true);
        DocumentBuilder builder = factory.newDocumentBuilder();
        Document parse = builder.parse(new InputSource(new StringReader(document)));
        
        transformer.transform(new DOMSource(parse), new StreamResult(writer));
    }
    
}