selectNodeIterator() problem

[Prashanth reddy]

Hi I have a SOAP file.... i converted into string.
i would like to search the value of a perticular node.

The soap String is:
<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:soapenc="http://schemas.xmlsoap.org/soap/encoding/" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"><soapenv:Body><GetQuoteRequest xmlns="http://schemas.vanguard.com/StockQuote"><symbol xmlns="">wqw</symbol><company xmlns="">qwq</company></GetQuoteRequest></soapenv:Body></soapenv:Envelope>

the program to look for perticular node is
public XPathNavigator(String xmlSource) throws TransformerException{
if ( xmlSource!=null) {
Debug.println("XPath xml=" + xmlSource);
String xpath = "/Envelope/Body/GetQuoteRequest/symbol";
InputSource inputSource = new InputSource(new ByteArrayInputStream(xmlSource.getBytes()));
DocumentBuilderFactory dfactory = DocumentBuilderFactory.newInstance();
try {
root = dfactory.newDocumentBuilder().parse(inputSource);
NodeIterator nodeIterator = XPathAPI.selectNodeIterator(root, xpath);
Node node = nodeIterator.nextNode();
System.out.println("the node u r searching is : " + node.getNodeName());
System.out.println("value of the node : " + node.getNodeValue());

}
catch (ParserConfigurationException pce) {
throw new TransformerException(pce.getMessage());
}
catch (IOException ioe) {
throw new TransformerException(ioe.getMessage());
}
catch (SAXException se){
throw new TransformerException(se.getMessage());
}


}

I am getting the node.But the value of the node am getting is null


PLZ help me ....

[Peer Reynders]

If you check the table of the API documentation org.w3c.dom Interface Node you will find that for an Element getNodeValue() will always return null. So either use the Node's getTextContent() method instead or append "/child::text()" to your XPath expression.

import java.io.StringReader;
import org.xml.sax.InputSource;
import org.w3c.dom.NodeList; 
import org.w3c.dom.Node; 
import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathFactory;
import javax.xml.xpath.XPath;
import javax.xml.xpath.XPathExpression;
 
import javax.xml.namespace.NamespaceContext;
import java.util.Iterator;
import java.util.Map;
import java.util.HashMap;
import java.util.Set;
import java.util.ArrayList;
import java.util.List;
 
class MyNamespaceContext implements NamespaceContext {
    private Map<String,String> map;
    public MyNamespaceContext() {
        map = new HashMap<String,String>();
    }
    public void setNamespace(String prefix, String namespaceURI) {
        map.put(prefix, namespaceURI);
    }
    public String getNamespaceURI(String prefix) {
        // !!! doesn't fully follow getNamespaceURI API spec !!!
        return (String) map.get(prefix);
    }
    public String getPrefix(String namespaceURI) {
        // !!! doesn't fully follow getPrefix API spec !!!
        Set keys = map.keySet();
        for (Iterator iterator = keys.iterator(); iterator.hasNext() :wink:  {
            String prefix = (String) iterator.next();
            String uri = (String) map.get(prefix);
            if (uri.equals(namespaceURI)) return prefix;
        }
        return null;
    }
    public Iterator getPrefixes(String namespaceURI) {
        // !!! doesn't fully follow getPrefixes API spec !!!
        List<String> prefixes = new ArrayList<String>();
        Set keys = map.keySet();
        for (Iterator iterator = keys.iterator(); iterator.hasNext() :wink:  {
            String prefix = (String) iterator.next();
            String uri = (String) map.get(prefix);
            if (uri.equals(namespaceURI)) prefixes.add(prefix);
        }
        return prefixes.iterator();
    }
}
 
public class Test {
    
    public static void main( String[] args ) throws Exception {
 
        String xmlSource = "<soapenv:Envelope xmlns:soapenv=\"http://schemas.xmlsoap.org/soap/envelope/\""
             + " xmlns:soapenc=\"http://schemas.xmlsoap.org/soap/encoding/\" xmlns:xsd=\"http://www.w3.org/2001/XMLSchema\""
             + " xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\">"
             + "<soapenv:Body><GetQuoteRequest xmlns=\"http://schemas.vanguard.com/StockQuote\">"
             + "<symbol xmlns=\"\">wqw</symbol>"
             + "<company xmlns=\"\">qwq</company>"
             + "</GetQuoteRequest></soapenv:Body></soapenv:Envelope>";
 
        XPathFactory factory    = XPathFactory.newInstance();
        XPath xPath             = factory.newXPath();
        InputSource inputSource = new InputSource( new StringReader(xmlSource) );
 
/*      Pure XPath expression solution
        String expression = "/*[namespace-uri()='http://schemas.xmlsoap.org/soap/envelope/' and local-name()='Envelope']"
                + "/*[namespace-uri()='http://schemas.xmlsoap.org/soap/envelope/' and local-name()='Body']"
                + "/*[namespace-uri()='http://schemas.vanguard.com/StockQuote' and local-name()='GetQuoteRequest']"
                + "/symbol/child::text()";
*/
 
        // Alternative 2 - generate XPath expanded-names via NamespaceContext interface
        MyNamespaceContext nsc = new MyNamespaceContext();
        // Use prefixes used in the query - NOT the ones in the document
        nsc.setNamespace( "soap", "http://schemas.xmlsoap.org/soap/envelope/" );
        nsc.setNamespace( "stockq", "http://schemas.vanguard.com/StockQuote" );
        xPath.setNamespaceContext( nsc );
        String expression = "/soap:Envelope/soap:Body/stockq:GetQuoteRequest/symbol/child::text()";
        // End Alternative 2 
 
        XPathExpression xpathExpression = xPath.compile( expression );
        NodeList nodes = (NodeList) xpathExpression.evaluate( inputSource, XPathConstants.NODESET );
        if (nodes.getLength() < 1) return;
 
        Node node = nodes.item( 0 );
        System.out.println("Node Name : " + node.getNodeName());
        System.out.println("Node Value : " + node.getNodeValue());
    }
}
 

Parsing an XML Document with XPath
Parsing a Namespace node with JDK 5.0

[Prashanth reddy]

hi,

It is simply SUPERB....u r the man....
Thanks alot

Pramod Reddy