Traverse the DOM tree using TreeWalker : DOM Tree « XML « Java Tutorial

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;

import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.traversal.DocumentTraversal;
import org.w3c.dom.traversal.NodeFilter;
import org.w3c.dom.traversal.TreeWalker;

public class Main {
  public static void main(String[] argv) throws Exception {
    DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
    DocumentBuilder loader = factory.newDocumentBuilder();
    Document document = loader.parse("sample.xml");

    DocumentTraversal traversal = (DocumentTraversal) document;

    TreeWalker walker = traversal.createTreeWalker(document.getDocumentElement(),
        NodeFilter.SHOW_ELEMENT, null, true);

    traverseLevel(walker, "");

  private static final void traverseLevel(TreeWalker walker, String indent) {
    Node parend = walker.getCurrentNode();
    System.out.println(indent + "- " + ((Element) parend).getTagName());

    for (Node n = walker.firstChild(); n != null; n = walker.nextSibling()) {
      traverseLevel(walker, indent + '\t');

33.4.DOM Tree
33.4.1.Creating a new DOM tree
33.4.2.Create new DOM tree with fully qualified element names
33.4.3.Custom complex filters for selecting nodes
33.4.4.Traverse the DOM tree as a list
33.4.5.Traverse the DOM tree using TreeWalker
33.4.6.Accessing different types of DOM tree nodes
33.4.7.Reading a DOM tree from XML document
33.4.8.Using ranges in DOM tree
33.4.9.Copying a Subtree of Nodes in a DOM Document
33.4.10.Copying a Subtree of Nodes from One DOM Document to Another
33.4.11.Get this Document's root node
33.4.12.Generates a DOM from scratch. Writes the DOM to a String using an LSSerializer.
33.4.13.Print Tree node
33.4.14.Traverse a DOM tree in order to print a document that is parsed