FULL PRODUCT VERSION :
java version "1.6.0_07"
Java(TM) SE Runtime Environment (build 1.6.0_07-b06)
Java HotSpot(TM) Client VM (build 10.0-b23, mixed mode, sharing)

ADDITIONAL OS VERSION INFORMATION :
Windows XP

A DESCRIPTION OF THE PROBLEM :
When running a XPath query like:

//z:row

against
<?xml version="1.0" encoding="utf-8"?>
<test xmlns:rs="urn:schemas-microsoft-com:rowset"
     xmlns:z="#RowsetSchema">
<rs:data>
  <z:row>XX</z:row>
</rs:data>
</test>

I get the following error:
javax.xml.transform.TransformerException:A location step was expected following the '/' or '//' token.

The problem is the # sign in the xmlns:z="#RowsetSchema". If I rename the namespace to be just xmlns:z="RowsetSchema" then it works fine.

This is an issue as Microsoft sharepoint webservices namespaces start with a #.


STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
The following code shows a working and failing example:

import com.sun.org.apache.xerces.internal.parsers.DOMParser;
import java.io.StringReader;
import java.util.Iterator;
import javax.xml.XMLConstants;
import javax.xml.namespace.NamespaceContext;
import javax.xml.transform.TransformerException;
import javax.xml.xpath.XPath;
import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathExpressionException;
import javax.xml.xpath.XPathFactory;
import org.w3c.dom.Document;
import org.w3c.dom.NodeList;
import org.xml.sax.InputSource;
 
public class TestXPath {
 
    public static void main(String[] args) {
        try {
            System.out.println("Running Test 1");
            String test1 = "<?xml version=\"1.0\" encoding=\"utf-8\"?>" +
                    "<test xmlns:rs=\"urn:schemas-microsoft-com:rowset\" xmlns:z=\"#RowsetSchema\">" +
                        "<rs:data>" +
                            "<z:row>XX</z:row>" +
                        "</rs:data>" +
                    "</test>";
            DOMParser parser = new DOMParser();
            parser.parse(new InputSource(new StringReader(test1)));
            runXpathQueryTest( parser.getDocument(), "//z:row");
        } catch (Exception e) {
            e.printStackTrace(System.out);
        }
 
        try {
            System.out.println("Running Test 2 - Only difference is we have changed '#RowsetSchema' to 'RowsetSchema'");
            String test1 = "<?xml version=\"1.0\" encoding=\"utf-8\"?>" +
                    "<test xmlns:rs=\"urn:schemas-microsoft-com:rowset\" xmlns:z=\"RowsetSchema\">" +
                        "<rs:data>" +
                            "<z:row>XX</z:row>" +
                        "</rs:data>" +
                    "</test>";
            DOMParser parser = new DOMParser();
            parser.parse(new InputSource(new StringReader(test1)));
            runXpathQueryTest( parser.getDocument(), "//z:row");
        } catch (Exception e) {
            e.printStackTrace(System.out);
        }
 
    }
 
    private static void runXpathQueryTest(Document document, String xPathExpression)
            throws XPathExpressionException, TransformerException {
 
 
        XPath xPath = XPathFactory.newInstance().newXPath();
        xPath.setNamespaceContext(new UniversalNamespaceResolver(document));
 
        NodeList result1 = (NodeList) xPath.evaluate( xPathExpression, document, XPathConstants.NODESET);
        System.out.println(xPathExpression + " returned " + result1.getLength() + " matching node(s)");
    }
 
    static class UniversalNamespaceResolver implements NamespaceContext {
        private Document sourceDocument;
 
        public UniversalNamespaceResolver(Document document) {
            sourceDocument = document;
        }
 
        public String getNamespaceURI(String prefix) {
            if (prefix.equals(XMLConstants.DEFAULT_NS_PREFIX)) {
                return sourceDocument.lookupNamespaceURI(null);
            } else {
                return sourceDocument.lookupNamespaceURI(prefix);
            }
        }
 
        public String getPrefix(String namespaceURI) {
            return sourceDocument.lookupPrefix(namespaceURI);
        }
 
        public Iterator getPrefixes(String namespaceURI) {
            // not implemented yet
            return null;
        }
    }
}


EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
Running Test 1
//z:row returned 1 matching node(s)

Running Test 2 - Only difference is we have changed '#RowsetSchema' to 'RowsetSchema'
//z:row returned 1 matching node(s)
ACTUAL -
Running Test 1
javax.xml.transform.TransformerException: A location step was expected following the '/' or '//' token.
        at com.sun.org.apache.xpath.internal.compiler.XPathParser.error(XPathParser.java:608)
        at com.sun.org.apache.xpath.internal.compiler.XPathParser.Step(XPathParser.java:1737)
        at com.sun.org.apache.xpath.internal.compiler.XPathParser.RelativeLocationPath(XPathParser.java:1624)
        at com.sun.org.apache.xpath.internal.compiler.XPathParser.LocationPath(XPathParser.java:1595)
        at com.sun.org.apache.xpath.internal.compiler.XPathParser.PathExpr(XPathParser.java:1315)
        at com.sun.org.apache.xpath.internal.compiler.XPathParser.UnionExpr(XPathParser.java:1234)
        at com.sun.org.apache.xpath.internal.compiler.XPathParser.UnaryExpr(XPathParser.java:1140)
        at com.sun.org.apache.xpath.internal.compiler.XPathParser.MultiplicativeExpr(XPathParser.java:1061)
        at com.sun.org.apache.xpath.internal.compiler.XPathParser.AdditiveExpr(XPathParser.java:1003)
        at com.sun.org.apache.xpath.internal.compiler.XPathParser.RelationalExpr(XPathParser.java:928)
        at com.sun.org.apache.xpath.internal.compiler.XPathParser.EqualityExpr(XPathParser.java:868)
        at com.sun.org.apache.xpath.internal.compiler.XPathParser.AndExpr(XPathParser.java:832)
        at com.sun.org.apache.xpath.internal.compiler.XPathParser.OrExpr(XPathParser.java:805)
        at com.sun.org.apache.xpath.internal.compiler.XPathParser.Expr(XPathParser.java:788)
        at com.sun.org.apache.xpath.internal.compiler.XPathParser.initXPath(XPathParser.java:127)
        at com.sun.org.apache.xpath.internal.XPath.<init>(XPath.java:176)
        at com.sun.org.apache.xpath.internal.XPath.<init>(XPath.java:264)
        at com.sun.org.apache.xpath.internal.jaxp.XPathImpl.eval(XPathImpl.java:193)
        at com.sun.org.apache.xpath.internal.jaxp.XPathImpl.evaluate(XPathImpl.java:275)
        at com.categoric.pindar.TestXPath.runXpathQueryTest(TestXPath.java:59)
        at com.categoric.pindar.TestXPath.main(TestXPath.java:30)
--------------- linked to ------------------
javax.xml.xpath.XPathExpressionException
        at com.sun.org.apache.xpath.internal.jaxp.XPathImpl.evaluate(XPathImpl.java:289)
        at com.categoric.pindar.TestXPath.runXpathQueryTest(TestXPath.java:59)
        at com.categoric.pindar.TestXPath.main(TestXPath.java:30)
 
...cut...
 
Running Test 2 - Only difference is we have changed '#RowsetSchema' to 'RowsetSchema'
//z:row returned 1 matching node(s)

ERROR MESSAGES/STACK TRACES THAT OCCUR :
javax.xml.transform.TransformerException: A location step was expected following the '/' or '//' token.
        at com.sun.org.apache.xpath.internal.compiler.XPathParser.error(XPathParser.java:608)
        at com.sun.org.apache.xpath.internal.compiler.XPathParser.Step(XPathParser.java:1737)
        at com.sun.org.apache.xpath.internal.compiler.XPathParser.RelativeLocationPath(XPathParser.java:1624)
        at com.sun.org.apache.xpath.internal.compiler.XPathParser.LocationPath(XPathParser.java:1595)
        at com.sun.org.apache.xpath.internal.compiler.XPathParser.PathExpr(XPathParser.java:1315)
        at com.sun.org.apache.xpath.internal.compiler.XPathParser.UnionExpr(XPathParser.java:1234)
        at com.sun.org.apache.xpath.internal.compiler.XPathParser.UnaryExpr(XPathParser.java:1140)
        at com.sun.org.apache.xpath.internal.compiler.XPathParser.MultiplicativeExpr(XPathParser.java:1061)
        at com.sun.org.apache.xpath.internal.compiler.XPathParser.AdditiveExpr(XPathParser.java:1003)
        at com.sun.org.apache.xpath.internal.compiler.XPathParser.RelationalExpr(XPathParser.java:928)
        at com.sun.org.apache.xpath.internal.compiler.XPathParser.EqualityExpr(XPathParser.java:868)
        at com.sun.org.apache.xpath.internal.compiler.XPathParser.AndExpr(XPathParser.java:832)
        at com.sun.org.apache.xpath.internal.compiler.XPathParser.OrExpr(XPathParser.java:805)
        at com.sun.org.apache.xpath.internal.compiler.XPathParser.Expr(XPathParser.java:788)
        at com.sun.org.apache.xpath.internal.compiler.XPathParser.initXPath(XPathParser.java:127)
        at com.sun.org.apache.xpath.internal.XPath.<init>(XPath.java:176)
        at com.sun.org.apache.xpath.internal.XPath.<init>(XPath.java:264)
        at com.sun.org.apache.xpath.internal.jaxp.XPathImpl.eval(XPathImpl.java:193)
        at com.sun.org.apache.xpath.internal.jaxp.XPathImpl.evaluate(XPathImpl.java:275)
        at com.categoric.pindar.TestXPath.runXpathQueryTest(TestXPath.java:59)
        at com.categoric.pindar.TestXPath.main(TestXPath.java:30)
--------------- linked to ------------------
javax.xml.xpath.XPathExpressionException
        at com.sun.org.apache.xpath.internal.jaxp.XPathImpl.evaluate(XPathImpl.java:289)
        at com.categoric.pindar.TestXPath.runXpathQueryTest(TestXPath.java:59)
        at com.categoric.pindar.TestXPath.main(TestXPath.java:30)
 

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
import com.sun.org.apache.xerces.internal.parsers.DOMParser;
import java.io.StringReader;
import java.util.Iterator;
import javax.xml.XMLConstants;
import javax.xml.namespace.NamespaceContext;
import javax.xml.transform.TransformerException;
import javax.xml.xpath.XPath;
import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathExpressionException;
import javax.xml.xpath.XPathFactory;
import org.w3c.dom.Document;
import org.w3c.dom.NodeList;
import org.xml.sax.InputSource;
 
public class TestXPath {
 
    public static void main(String[] args) {
        try {
            System.out.println("Running Test 1");
            String test1 = "<?xml version=\"1.0\" encoding=\"utf-8\"?>" +
                    "<test xmlns:rs=\"urn:schemas-microsoft-com:rowset\" xmlns:z=\"#RowsetSchema\">" +
                        "<rs:data>" +
                            "<z:row>XX</z:row>" +
                        "</rs:data>" +
                    "</test>";
            DOMParser parser = new DOMParser();
            parser.parse(new InputSource(new StringReader(test1)));
            runXpathQueryTest( parser.getDocument(), "//z:row");
        } catch (Exception e) {
            e.printStackTrace(System.out);
        }
 
        try {
            System.out.println("Running Test 2 - Only difference is we have changed '#RowsetSchema' to 'RowsetSchema'");
            String test1 = "<?xml version=\"1.0\" encoding=\"utf-8\"?>" +
                    "<test xmlns:rs=\"urn:schemas-microsoft-com:rowset\" xmlns:z=\"RowsetSchema\">" +
                        "<rs:data>" +
                            "<z:row>XX</z:row>" +
                        "</rs:data>" +
                    "</test>";
            DOMParser parser = new DOMParser();
            parser.parse(new InputSource(new StringReader(test1)));
            runXpathQueryTest( parser.getDocument(), "//z:row");
        } catch (Exception e) {
            e.printStackTrace(System.out);
        }
 
    }
 
    private static void runXpathQueryTest(Document document, String xPathExpression)
            throws XPathExpressionException, TransformerException {
 
 
        XPath xPath = XPathFactory.newInstance().newXPath();
        xPath.setNamespaceContext(new UniversalNamespaceResolver(document));
 
        NodeList result1 = (NodeList) xPath.evaluate( xPathExpression, document, XPathConstants.NODESET);
        System.out.println(xPathExpression + " returned " + result1.getLength() + " matching node(s)");
    }
 
    static class UniversalNamespaceResolver implements NamespaceContext {
        private Document sourceDocument;
 
        public UniversalNamespaceResolver(Document document) {
            sourceDocument = document;
        }
 
        public String getNamespaceURI(String prefix) {
            if (prefix.equals(XMLConstants.DEFAULT_NS_PREFIX)) {
                return sourceDocument.lookupNamespaceURI(null);
            } else {
                return sourceDocument.lookupNamespaceURI(prefix);
            }
        }
 
        public String getPrefix(String namespaceURI) {
            return sourceDocument.lookupPrefix(namespaceURI);
        }
 
        public Iterator getPrefixes(String namespaceURI) {
            // not implemented yet
            return null;
        }
    }
}
---------- END SOURCE ----------