Traverse the DOM tree as a list in Java

import java.io.StringReader;
/* w w w  .jav a  2 s  .c o  m*/
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.NodeIterator;
import org.xml.sax.InputSource;

public class Main {
  
  public static void main(String[] argv) throws Exception {
    StringReader sr = new StringReader("<tag>java2s.com</tag>");
    DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
    DocumentBuilder loader = factory.newDocumentBuilder();

    Document document = loader.parse(new InputSource(sr));

    DocumentTraversal traversal = (DocumentTraversal) document;

    NodeIterator iterator = traversal.createNodeIterator(document.getDocumentElement(),
        NodeFilter.SHOW_ALL, null, true);

    for (Node n = iterator.nextNode(); n != null; n = iterator.nextNode()) {
      System.out.println(n instanceof Element);
      
    }

  }
  
}