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

1. Java Tutorial
2. XML
3. DOM Tree

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');
    }
    walker.setCurrentNode(parend);
  }
}