How to read an XML file using XPath in Java

Question

Is there any simple way to read an XML file using XPath in Java?

Answer 1

Import the packages required to work with XPath:

import java.io.File;

import java.io.IOException;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.ParserConfigurationException;
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.w3c.dom.Node;
import org.w3c.dom.Element;
import org.xml.sax.SAXException;

Then create instances of DocumentBuilderFactory, DocumentBuilder and document:

public class XPathReaderDemo {


public static void main(String[] args) {


try {

         File inputFile = new File("D:\\students.txt");

         DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();

         DocumentBuilder dBuilder;


         dBuilder = dbFactory.newDocumentBuilder();


         Document doc = dBuilder.parse(inputFile);

         doc.getDocumentElement().normalize();


         XPath xPath =  XPathFactory.newInstance().newXPath();


         String expression = "/class/student";       

         NodeList nodeList = (NodeList) xPath.compile(expression).evaluate(

            doc, XPathConstants.NODESET);

for (int i = 0; i < nodeList.getLength(); i++) {

            Node nNode = nodeList.item(i);

            System.out.println("\nCurrent Element :" + nNode.getNodeName());

           

            if (nNode.getNodeType() == Node.ELEMENT_NODE) {

               Element eElement = (Element) nNode;

              

               System.out.println("First Name : "

                  + eElement

                  .getElementsByTagName("firstname")

                  .item(0)

                  .getTextContent());

               System.out.println("Last Name : "

                  + eElement

                  .getElementsByTagName("lastname")

                  .item(0)

                  .getTextContent());

               System.out.println("email : "

                  + eElement

                  .getElementsByTagName("email")

                  .item(0)

                  .getTextContent());

               System.out.println("Marks : "

                  + eElement

                  .getElementsByTagName("marks")

                  .item(0)

                  .getTextContent());

            }

         }

 } catch (ParserConfigurationException e) {

         e.printStackTrace();

      } catch (SAXException e) {

         e.printStackTrace();

      } catch (IOException e) {

         e.printStackTrace();

      } catch (XPathExpressionException e) {

         e.printStackTrace();

      }


  }


}