Java tutorial
import java.io.File; import javax.xml.parsers.DocumentBuilderFactory; import org.w3c.dom.Comment; import org.w3c.dom.Document; import org.w3c.dom.Element; import org.w3c.dom.NodeList; public class Main { public static void main(String[] argv) throws Exception { DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance(); factory.setValidating(true); factory.setExpandEntityReferences(false); Document doc = factory.newDocumentBuilder().parse(new File("filename")); // Find all elements with the name "entry" and append a comment NodeList list = doc.getElementsByTagName("entry"); for (int i = 0; i < list.getLength(); i++) { Element element = (Element) list.item(i); Comment comment = doc.createComment("index=" + i); // Add the comment after this element element.getParentNode().insertBefore(comment, element.getNextSibling()); } } }