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javaxalan

Reusing xalan transformer causing its extension functions break


I am using xalan 2.7.1 to validate my xml docs with xslt style sheet. It works fine for the first document and returns error message in case of error along with correct line and column number of xml source by making use of NodeInfo.lineNumber and NodeInfo.columnNumber extensions.

The problem is when I try to reuse transformer to validate other xml docs, it successfully transforms the document but always returns lineNumber=columnNumber=-1 for all errors.
Any idea?

Edit: Here is my code::

package mycompany;

import java.io.File;
import javax.xml.transform.ErrorListener;
import javax.xml.transform.Source;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerException;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.stream.StreamResult;
import javax.xml.transform.stream.StreamSource;
import org.apache.xalan.processor.TransformerFactoryImpl;

public class XsltTransformer {

    public static void main(String[] args) {

        TransformerFactory tFactory = TransformerFactory.newInstance();
        tFactory.setAttribute(TransformerFactoryImpl.FEATURE_SOURCE_LOCATION, Boolean.TRUE);

        StreamSource xsltStreamSource = new StreamSource(new File("E:\\Temp\\Test\\myXslt.xsl"));
        try {
            Transformer transformer = tFactory.newTransformer(xsltStreamSource);

            File srcFolder = new File("E:\\Temp\\Test");
            for (File file : srcFolder.listFiles()) {
                if (file.getName().endsWith("xml")) {

                    Source source = new StreamSource(file);
                    StreamResult result = new StreamResult(System.out);

                    XsltTransformer xsltTransformer = new XsltTransformer();
                    ErrorListenerImpl errorHandler = xsltTransformer.new ErrorListenerImpl();
                    transformer.setErrorListener(errorHandler);

                    transformer.transform(source, result);

                    if (errorHandler.e != null) {
                        System.out.println("Transformation Exception: " + errorHandler.e.getMessage());
                    }

                    transformer.reset();
                }
            }

        } catch (TransformerException e) {
            e.printStackTrace();
        }
    }

    private class ErrorListenerImpl implements ErrorListener {
        public TransformerException e = null;

        public void error(TransformerException exception) {
            this.e = exception;
        }

        public void fatalError(TransformerException exception) {
            this.e = exception;
        }

        public void warning(TransformerException exception) {
            this.e = exception;
        }
    }
}

Edit: Here are myXslt.xsl and XML sources:

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<axsl:stylesheet 
    xmlns:axsl="http://www.w3.org/1999/XSL/Transform" 
    xmlns:iso="http://purl.oclc.org/dsdl/schematron" 
    xmlns:sch="http://www.ascc.net/xml/schematron"
    version="1.0" 
    xmlns:nodeinfo="xalan://org.apache.xalan.lib.NodeInfo">

  <axsl:output 
      xmlns:svrl="http://purl.oclc.org/dsdl/svrl" 
      xmlns:schold="http://www.ascc.net/xml/schematron" 
      xmlns:xs="http://www.w3.org/2001/XMLSchema"
      indent="yes" 
      standalone="yes" 
      omit-xml-declaration="no" 
      method="xml" />

  <!--SCHEMA METADATA -->
  <axsl:template match="/">
    <svrl:schematron-output xmlns:svrl="http://purl.oclc.org/dsdl/svrl" xmlns:schold="http://www.ascc.net/xml/schematron" 
                            xmlns:xs="http://www.w3.org/2001/XMLSchema" schemaVersion="ISO19757-3" title="Test ISO schematron file. Introduction mode ">
      <svrl:active-pattern>
        <axsl:apply-templates />
      </svrl:active-pattern>
      <axsl:apply-templates mode="M1" select="/" />
    </svrl:schematron-output>
  </axsl:template>

  <!--RULE -->
  <axsl:template mode="M1" priority="1000" match="//*[@remote-property]">
    <svrl:fired-rule xmlns:svrl="http://purl.oclc.org/dsdl/svrl" xmlns:schold="http://www.ascc.net/xml/schematron" 
                     xmlns:xs="http://www.w3.org/2001/XMLSchema" context="//*[@remote-property]" />

    <!--ASSERT -->
    <axsl:choose>
      <axsl:when test="@remote-property = //@id or @remote-property = //@name" />
      <axsl:otherwise>
        <svrl:failed-assert xmlns:svrl="http://purl.oclc.org/dsdl/svrl" xmlns:schold="http://www.ascc.net/xml/schematron" 
                            xmlns:xs="http://www.w3.org/2001/XMLSchema" test="@remote-property = //@id or @remote-property = //@name">
          <axsl:attribute name="lineNumber">
              <axsl:value-of select="nodeinfo:lineNumber()" />
          </axsl:attribute>
          <axsl:attribute name="columnNumber">
              <axsl:value-of select="nodeinfo:columnNumber()" />
          </axsl:attribute>
          <svrl:text>
            Invalid remote-property: remote class element with this id or name does not exists
      </svrl:text>
        </svrl:failed-assert>
      </axsl:otherwise>
    </axsl:choose>
  </axsl:template>
</axsl:stylesheet>

source1.xml:

<?xml version="1.0" encoding="UTF-8"?>
<root>
    <remote-service>
        <class name="Table1" table="table1">
            <id name="col1"/>
            <property name="col2"/>
        </class>
    </remote-service>
    <application>
        <text-field name="field1" remote-property="col1X"/>
    </application>
</root> 

and source2.xml

<?xml version="1.0" encoding="UTF-8"?>
<root>
    <application>
        <text-field name="field1" remote-property="col1Z"/>
    </application>
</root> 

Solution

  • The javadoc states:

    The reset Transformer is not guaranteed to have the same URIResolver or ErrorListener Objects

    You might have to reset your ErrorListener reference to the new ErrorListener of the reset transformer.

    update

    I have no experience with the schematron library, from what I see it is probably an issue of that library being used by a reset transformer.

    If you cannot get it to work resetting the transformer you might be able to use the XSL template facility to prevent having to interpret the XSL sheet on every transorm:

    import javax.xml.transform.TransformerFactory;
    import javax.xml.transform.Templates;
    import javax.xml.transform.Transformer;
    
    TransformerFactory factory = TransformerFactory.newInstance();
    
    Templates xslTemplate = factory.newTemplates(new StreamSource(new StringReader(xsl)));
    

    Later re-use the template by getting the transformer from it:

    Transformer transformer = xslTemplate.newTransformer();