data.xml

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
    <asd>asdasd</asd>
    <asd2>a</asd2>
</configuration>

Main_XPath.java

import org.w3c.dom.*;
import org.xml.sax.SAXException;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerConfigurationException;
import javax.xml.transform.TransformerFactory;
import javax.xml.xpath.XPath;
import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathExpressionException;
import javax.xml.xpath.XPathFactory;
import java.io.IOException;

public class Main_XPath {
    public static void main(String[] args) throws ParserConfigurationException, IOException, SAXException, XPathExpressionException, TransformerConfigurationException {
        String filename = "data.xml";
        DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();

        DocumentBuilder builder = factory.newDocumentBuilder();
        Document document = builder.parse(filename);

        Element rootElement = document.getDocumentElement();
        rootElement.normalize();

        XPathFactory xPathFactory = XPathFactory.newInstance();
        XPath xPath = xPathFactory.newXPath();
        String XPathString = "/configuration/*";
//        rootElement.getElementsByTagName("configuration").item(0).getChildNodes()
        TransformerFactory tf = TransformerFactory.newInstance();
        Transformer transformer = tf.newTransformer();

        transformer.setParameter("a","a");

        NodeList titles = (NodeList) xPath.evaluate(XPathString, document, XPathConstants.NODESET);
        for (int i = 0; i < titles.getLength(); i++) {
            Node n = titles.item(i);

            System.out.println(n.getNodeName() + " = " + n.getTextContent());
        }
    }
}