XPATH issue

[sai rama krishna]

I have xpath similar to below

<xPath>concat(deviceNbr, '|', nbr)</xPath>
<selectionRule>NODES_FROM_DOC</selectionRule>


In my generated document i do not see any thing getting printed.
Some times it prints only top element but not the subsequent element data. Please advise on how to fix this issue. Any sample examples on this highly appreciated. Thanks in advance

[Campbell Ritchie]

Too difficult for “beginning”. Moving discussion.

[Mauro Trevigno]

What are you trying to do?

Xpath is a syntax that allows search data & nodes in a XML file.

<?xml version="1.0" encoding="UTF-8"?> <colors> <pencil name="Favorite"> <model nombre="1212"> <color name="Red" /> <color name="Yellow" /> <color name="Green"> <eraser name="White" /> </color> </model> </pencil> <colors>

import java.io.File;
 
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.xpath.XPath;
import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathFactory;
 
import org.w3c.dom.Document;
import org.w3c.dom.NodeList;
 
public class XPathTest {
    public static void main(String[] args) throws Exception {
                // Xpath search expression
        String xPathExpression = "//eraser[@name='White']";
         
                // Load XML Document
        DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
        DocumentBuilder builder = factory.newDocumentBuilder();
        Document document = builder.parse(new File("testJavaRanch.xml"));
 
        // Prepare Xpath
        XPath xpath = XPathFactory.newInstance().newXPath();
 
        // Search
        NodeList nodes = (NodeList) xpath.evaluate(xPathExpression, document, XPathConstants.NODESET);
 
        for (int i=0;i<nodes.getLength();i++){
            System.out.println(nodes.item(i).getNodeName()+" : " +
                           nodes.item(i).getAttributes().getNamedItem("name"));
        }
    }
}

Under XpathExpression you can search by expression for example:
/colors/pencil/model/color, this will print all the colors.

or by attribute like the example.


-Mauro.