Java Tutorial/XML/DOM Tree

Accessing different types of DOM tree nodes

   <source lang="java">

import javax.xml.parsers.DocumentBuilder; import javax.xml.parsers.DocumentBuilderFactory; import org.w3c.dom.Attr; import org.w3c.dom.CharacterData; import org.w3c.dom.rument; import org.w3c.dom.Document; import org.w3c.dom.Element; import org.w3c.dom.Node; import org.w3c.dom.NodeList; import org.w3c.dom.Text; 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");
   Element purchaseOrder = document.getDocumentElement();
   printElement(purchaseOrder, "");
 }
 static void printElement(Element element, String indent) {
   System.out.println("Element "" + element.getNodeName() + """);
   NodeList children = element.getChildNodes();
   for (int i = 0; i < children.getLength(); i++) {
     Node child = children.item(i);
     switch (child.getNodeType()) {
     case Node.ELEMENT_NODE:
       printElement((Element) child, indent + "\t");
       break;
     case Node.ATTRIBUTE_NODE:
       Attr attr = (Attr) child;
       System.out.println("\tAttribute: "" + attr.getName() + "" = "" + attr.getValue() + """);
       break;
     case Node.ruMENT_NODE:
       Comment comment = (Comment) child;
       System.out.println("\tComment: "" + comment.getData() + """);
       break;
     case Node.CDATA_SECTION_NODE:
       CharacterData cdata = (CharacterData) child;
       System.out.println("\tCDatat: "" + cdata.getData() + """);
       break;
     case Node.TEXT_NODE:
       Text text = (Text) child;
       System.out.println("\tText: "" + text.getData() + """);
       break;
     default:
       System.out.println("\tUnknown node type: "" + child.getNodeType() + """);
       break;
     }
   }
 }

}</source>

Copying a Subtree of Nodes from One DOM Document to Another

   <source lang="java">

import java.io.File; import javax.xml.parsers.DocumentBuilderFactory; import org.w3c.dom.Document; import org.w3c.dom.Element; import org.w3c.dom.Node; 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 doc1 = factory.newDocumentBuilder().parse(new File("filename"));
   NodeList list = doc1.getElementsByTagName("entry");
   Element element = (Element) list.item(0);
   Document doc2 = factory.newDocumentBuilder().parse(new File("infilename2.xml"));
   Node dup = doc2.importNode(element, true);
   doc2.getDocumentElement().appendChild(dup);
 }

}</source>

Copying a Subtree of Nodes in a DOM Document

   <source lang="java">

import java.io.File; import javax.xml.parsers.DocumentBuilderFactory; 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"));
   NodeList list = doc.getElementsByTagName("entry");
   Element element = (Element) list.item(0);
   Element dup = (Element) element.cloneNode(true);
   element.getParentNode().insertBefore(dup, element.getNextSibling());
 }

}</source>

Create new DOM tree with fully qualified element names

   <source lang="java">

import javax.xml.parsers.DocumentBuilder; import javax.xml.parsers.DocumentBuilderFactory; import org.w3c.dom.Document; import org.w3c.dom.Element; public class Main {

 public static void main(String[] argv) throws Exception {
   DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
   factory.setNamespaceAware(true);
   DocumentBuilder loader = factory.newDocumentBuilder();
   Document document = loader.newDocument();
   String docNS = "http://www.my-company.ru";
   Element order = document.createElementNS(docNS, "order");
   document.appendChild(order);
   order.setAttribute("xmlns", docNS);
 }

}</source>

Creating a new DOM tree

   <source lang="java">

import javax.xml.parsers.DocumentBuilder; import javax.xml.parsers.DocumentBuilderFactory; import org.w3c.dom.Document; import org.w3c.dom.Element; public class Main {

 public static void main(String[] argv) throws Exception {
   DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
   DocumentBuilder loader = factory.newDocumentBuilder();
   Document document = loader.newDocument();
   Element root = document.createElement("order");
   document.appendChild(root);
 }

}</source>

Custom complex filters for selecting nodes

   <source lang="java">

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; 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;
   NodeIterator iterator = traversal.createNodeIterator(document.getDocumentElement(),
       NodeFilter.SHOW_ALL, new ItemFilter(), true);
   for (Node n = iterator.nextNode(); n != null; n = iterator.nextNode()) {
     System.out.println("Element: " + ((Element) n).getTagName());
   }
 }
 private static final class ItemFilter implements NodeFilter {
   public short acceptNode(Node n) {
     if (n instanceof Element) {
       if (((Element) n).getTagName().equals("item")) {
         return NodeFilter.FILTER_ACCEPT;
       }
     }
     return NodeFilter.FILTER_REJECT;
   }
 }

}</source>

Generates a DOM from scratch. Writes the DOM to a String using an LSSerializer.

   <source lang="java">

/*

* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements.  See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License.  You may obtain a copy of the License at
* 
*      http://www.apache.org/licenses/LICENSE-2.0
* 
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/

import java.io.StringWriter; import javax.xml.parsers.DocumentBuilder; import javax.xml.parsers.DocumentBuilderFactory; import org.w3c.dom.Document; import org.w3c.dom.Element; import org.w3c.dom.bootstrap.DOMImplementationRegistry; import org.w3c.dom.ls.DOMImplementationLS; import org.w3c.dom.ls.LSOutput; import org.w3c.dom.ls.LSSerializer; /**

* Simple Sample that: - Generates a DOM from scratch. - Writes the DOM to a
* String using an LSSerializer
* 
* @author Jeffrey Rodriguez
* @version $Id: DOMGenerate.java 546623 2007-06-12 20:25:08Z mrglavas $
*/

public class DOMGenerate {

 public static void main(String[] argv) {
   try {
     DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
     dbf.setNamespaceAware(true);
     DocumentBuilder db = dbf.newDocumentBuilder();
     Document doc = db.newDocument();
     Element root = doc.createElementNS(null, "person"); // Create Root Element
     Element item = doc.createElementNS(null, "name"); // Create element
     item.appendChild(doc.createTextNode("Jeff"));
     root.appendChild(item); // Attach element to Root element
     item = doc.createElementNS(null, "age"); // Create another Element
     item.appendChild(doc.createTextNode("28"));
     root.appendChild(item); // Attach Element to previous element down tree
     item = doc.createElementNS(null, "height");
     item.appendChild(doc.createTextNode("1.80"));
     root.appendChild(item); // Attach another Element - grandaugther
     doc.appendChild(root); // Add Root to Document
     DOMImplementationRegistry registry = DOMImplementationRegistry.newInstance();
     DOMImplementationLS domImplLS = (DOMImplementationLS) registry.getDOMImplementation("LS");
     LSSerializer ser = domImplLS.createLSSerializer(); // Create a serializer
                                                         // for the DOM
     LSOutput out = domImplLS.createLSOutput();
     StringWriter stringOut = new StringWriter(); // Writer will be a String
     out.setCharacterStream(stringOut);
     ser.write(doc, out); // Serialize the DOM
     System.out.println("STRXML = " + stringOut.toString()); // Spit out the
                                                             // DOM as a String
   } catch (Exception ex) {
     ex.printStackTrace();
   }
 }

}</source>

Get this Document"s root node

   <source lang="java">

import org.w3c.dom.Document; import org.w3c.dom.Element;

public class Main {

 // return this Document"s root node
 public static Element getRoot(Document doc) {
     return doc.getDocumentElement();
 } // getRoot(Document(:  Element
 

}</source>

Print Tree node

   <source lang="java">

import java.lang.reflect.Field; import java.lang.reflect.InvocationTargetException; import java.lang.reflect.Method; import java.util.ArrayList; import java.util.Arrays; import java.util.HashSet; import java.util.List; import java.util.Locale; import java.util.Map; import java.util.Set; import javax.servlet.http.HttpServletResponse; import org.w3c.dom.NamedNodeMap; import org.w3c.dom.Node; import org.w3c.dom.NodeList; /*

* Copyright 2005 Joe Walker
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
*     http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/

/**

* 
* @author Abey Mullassery
* 
*/

public class Main {

 public static void printTree(Node doc) {
   if (doc == null) {
     System.out.println("Nothing to print!!");
     return;
   }
   try {
     System.out.println(doc.getNodeName() + "  " + doc.getNodeValue());
     NamedNodeMap cl = doc.getAttributes();
     for (int i = 0; i < cl.getLength(); i++) {
       Node node = cl.item(i);
       System.out.println(
         "\t" + node.getNodeName() + " ->" + node.getNodeValue());
     }
     NodeList nl = doc.getChildNodes();
     for (int i = 0; i < nl.getLength(); i++) {
       Node node = nl.item(i);
       printTree(node);
     }
   } catch (Throwable e) {
     System.out.println("Cannot print!! " + e.getMessage());
   }
 }

}</source>

Reading a DOM tree from XML document

   <source lang="java">

import javax.xml.parsers.DocumentBuilder; import javax.xml.parsers.DocumentBuilderFactory; import org.w3c.dom.Document; import org.w3c.dom.Element; 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");
   Element tree = document.getDocumentElement();
 }

}</source>

Traverse a DOM tree in order to print a document that is parsed

   <source lang="java">

/*

*
* The Apache Software License, Version 1.1
*
* Copyright (c) 1999 The Apache Software Foundation.  All rights 
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
*    notice, this list of conditions and the following disclaimer. 
*
* 2. Redistributions in binary form must reproduce the above copyright
*    notice, this list of conditions and the following disclaimer in
*    the documentation and/or other materials provided with the
*    distribution.
*
* 3. The end-user documentation included with the redistribution, if
*    any, must include the following acknowlegement:  
*       "This product includes software developed by the 
*        Apache Software Foundation (http://www.apache.org/)."
*    Alternately, this acknowlegement may appear in the software itself,
*    if and wherever such third-party acknowlegements normally appear.
*
* 4. The names "The Jakarta Project", "Tomcat", and "Apache Software
*    Foundation" must not be used to endorse or promote products derived
*    from this software without prior written permission. For written 
*    permission, please contact apache@apache.org.
*
* 5. Products derived from this software may not be called "Apache"
*    nor may "Apache" appear in their names without prior written
*    permission of the Apache Group.
*
* THIS SOFTWARE IS PROVIDED ``AS IS"" AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation.  For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*/

// $Id: DOMWriter.java 2891 2008-07-31 16:03:02Z thomas.diesler@jboss.ru $ import java.io.OutputStream; import java.io.OutputStreamWriter; import java.io.PrintWriter; import java.io.StringWriter; import java.io.UnsupportedEncodingException; import java.io.Writer; import java.util.HashMap; import java.util.Iterator; import java.util.Map; import org.w3c.dom.Attr; import org.w3c.dom.Element; import org.w3c.dom.NamedNodeMap; import org.w3c.dom.Node; import org.w3c.dom.NodeList; /**

* Traverse a DOM tree in order to print a document that is parsed.
* 
* @author Andy Clark, IBM
* @author Thomas.Diesler@jboss.org
*/

@SuppressWarnings("unchecked") public class DOMWriter {

 // Print writer
 private PrintWriter out;
 // True, if canonical output
 private boolean canonical;
 // True, if pretty printing should be used
 private boolean prettyprint;
 // True, if the XML declaration should be written
 private boolean writeXMLDeclaration;
 // True, if whitespace should be ignored
 private boolean ignoreWhitespace;
 // Explicit character set encoding
 private String charsetName;
 // indent for the pretty printer
 private int prettyIndent;
 // True, if the XML declaration has been written
 private boolean wroteXMLDeclaration;
 // The node that started the write
 private Node rootNode;
 // True if we want namespace completion
 private boolean completeNamespaces = true;
 // The current default namespace
 private String currentDefaultNamespace;
 public DOMWriter(Writer w) {
   this.out = new PrintWriter(w);
 }
 public DOMWriter(Writer w, String charsetName) {
   this.out = new PrintWriter(w);
   this.charsetName = charsetName;
   this.writeXMLDeclaration = true;
 }
 public DOMWriter(OutputStream stream) {
   try {
     this.out = new PrintWriter(new OutputStreamWriter(stream, "UTF-8"));
   } catch (UnsupportedEncodingException e) {
     // ignore, UTF-8 should be available
   }
 }
 public DOMWriter(OutputStream stream, String charsetName) {
   try {
     this.out = new PrintWriter(new OutputStreamWriter(stream, charsetName));
     this.charsetName = charsetName;
     this.writeXMLDeclaration = true;
   } catch (UnsupportedEncodingException e) {
     throw new IllegalArgumentException("Unsupported encoding: " + charsetName);
   }
 }
 /**
  * Print a node with explicit prettyprinting. The defaults for all other
  * DOMWriter properties apply.
  * 
  */
 public static String printNode(Node node, boolean prettyprint) {
   StringWriter strw = new StringWriter();
   new DOMWriter(strw).setPrettyprint(prettyprint).print(node);
   return strw.toString();
 }
 public boolean isCanonical() {
   return canonical;
 }
 /**
  * Set wheter entities should appear in their canonical form. The default is
  * false.
  */
 public DOMWriter setCanonical(boolean canonical) {
   this.canonical = canonical;
   return this;
 }
 public boolean isIgnoreWhitespace() {
   return ignoreWhitespace;
 }
 /**
  * Set whether whitespace should be ignored. The default is false.
  */
 public DOMWriter setIgnoreWhitespace(boolean ignoreWhitespace) {
   this.ignoreWhitespace = ignoreWhitespace;
   return this;
 }
 /**
  * Set wheter subelements should have their namespaces completed. Setting this
  * to false may lead to invalid XML fragments. The default is true.
  */
 public DOMWriter setCompleteNamespaces(boolean complete) {
   this.rupleteNamespaces = complete;
   return this;
 }
 public boolean isPrettyprint() {
   return prettyprint;
 }
 /**
  * Set wheter element should be indented. The default is false.
  */
 public DOMWriter setPrettyprint(boolean prettyprint) {
   this.prettyprint = prettyprint;
   return this;
 }
 public boolean isWriteXMLDeclaration() {
   return writeXMLDeclaration;
 }
 /**
  * Set wheter the XML declaration should be written. The default is false.
  */
 public DOMWriter setWriteXMLDeclaration(boolean flag) {
   this.writeXMLDeclaration = flag;
   return this;
 }
 public void print(Node node) {
   if (prettyprint && ignoreWhitespace)
     throw new IllegalStateException("Cannot pretty print and ignore whitespace");
   rootNode = node;
   printInternal(node, false);
 }
 private void printInternal(Node node, boolean indentEndMarker) {
   // is there anything to do?
   if (node == null) {
     return;
   }
   // JBAS-2117 - Don"t skip the DOCUMENT_NODE
   // if (node instanceof Document) node =
   // ((Document)node).getDocumentElement();
   if (wroteXMLDeclaration == false && writeXMLDeclaration == true && canonical == false) {
     out.print("<?xml version="1.0"");
     if (charsetName != null)
       out.print(" encoding="" + charsetName + """);
     out.print("?>");
     if (prettyprint)
       out.println();
     wroteXMLDeclaration = true;
   }
   int type = node.getNodeType();
   boolean hasChildNodes = node.getChildNodes().getLength() > 0;
   String nodeName = node.getNodeName();
   switch (type) {
   // print document
   case Node.DOCUMENT_NODE: {
     NodeList children = node.getChildNodes();
     for (int iChild = 0; iChild < children.getLength(); iChild++) {
       printInternal(children.item(iChild), false);
     }
     out.flush();
     break;
   }
   // print element with attributes
   case Node.ELEMENT_NODE: {
     Element element = (Element) node;
     if (prettyprint) {
       for (int i = 0; i < prettyIndent; i++) {
         out.print(" ");
       }
       prettyIndent++;
     }
     out.print("<");
     out.print(nodeName);
     Map nsMap = new HashMap();
     String elPrefix = node.getPrefix();
     String elNamespaceURI = node.getNamespaceURI();
     if (elPrefix != null) {
       String nsURI = getNamespaceURI(elPrefix, element, rootNode);
       nsMap.put(elPrefix, nsURI);
     }
     Attr attrs[] = sortAttributes(node.getAttributes());
     for (int i = 0; i < attrs.length; i++) {
       Attr attr = attrs[i];
       String atPrefix = attr.getPrefix();
       String atName = attr.getNodeName();
       String atValue = normalize(attr.getNodeValue(), canonical);
       if (atName.equals("xmlns"))
         currentDefaultNamespace = atValue;
       if (atPrefix != null && !atPrefix.equals("xmlns") && !atPrefix.equals("xml")) {
         String nsURI = getNamespaceURI(atPrefix, element, rootNode);
         nsMap.put(atPrefix, nsURI);
         // xsi:type="ns1:SubType", xsi:type="xsd:string"
         if (atName.equals(atPrefix + ":type") && atValue.indexOf(":") > 0) {
           // xsi defined on the envelope
           if (nsURI == null)
             nsURI = getNamespaceURI(atPrefix, element, null);
           if ("http://www.w3.org/2001/XMLSchema-instance".equals(nsURI)) {
             String typePrefix = atValue.substring(0, atValue.indexOf(":"));
             String typeURI = getNamespaceURI(typePrefix, element, rootNode);
             nsMap.put(typePrefix, typeURI);
           }
         }
       }
       out.print(" " + atName + "="" + atValue + """);
     }
     // Add namespace declaration for prefixes
     // that are defined further up the tree
     if (completeNamespaces) {
       Iterator itPrefix = nsMap.keySet().iterator();
       while (itPrefix.hasNext()) {
         String prefix = (String) itPrefix.next();
         String nsURI = (String) nsMap.get(prefix);
         if (nsURI == null) {
           nsURI = getNamespaceURI(prefix, element, null);
           out.print(" xmlns:" + prefix + "="" + nsURI + """);
         }
       }
     }
     // The SAX ContentHandler will by default not add the namespace
     // declaration
     // <Hello xmlns="http://somens">World</Hello>
     if (elPrefix == null && elNamespaceURI != null) {
       String defaultNamespace = element.getAttribute("xmlns");
       if (defaultNamespace.length() == 0 && !elNamespaceURI.equals(currentDefaultNamespace)) {
         out.print(" xmlns="" + elNamespaceURI + """);
         currentDefaultNamespace = elNamespaceURI;
       }
     }
     if (hasChildNodes) {
       out.print(">");
     }
     // Find out if the end marker is indented
     indentEndMarker = isEndMarkerIndented(node);
     if (indentEndMarker) {
       out.print("\n");
     }
     NodeList childNodes = node.getChildNodes();
     int len = childNodes.getLength();
     for (int i = 0; i < len; i++) {
       Node childNode = childNodes.item(i);
       printInternal(childNode, false);
     }
     break;
   }
   // handle entity reference nodes
   case Node.ENTITY_REFERENCE_NODE: {
     if (canonical) {
       NodeList children = node.getChildNodes();
       if (children != null) {
         int len = children.getLength();
         for (int i = 0; i < len; i++) {
           printInternal(children.item(i), false);
         }
       }
     } else {
       out.print("&");
       out.print(nodeName);
       out.print(";");
     }
     break;
   }
   // print cdata sections
   case Node.CDATA_SECTION_NODE: {
     if (canonical) {
       out.print(normalize(node.getNodeValue(), canonical));
     } else {
       out.print("<![CDATA[");
       out.print(node.getNodeValue());
       out.print("]]>");
     }
     break;
   }
   // print text
   case Node.TEXT_NODE: {
     String text = normalize(node.getNodeValue(), canonical);
     if (text.trim().length() > 0) {
       out.print(text);
     } else if (prettyprint == false && ignoreWhitespace == false) {
       out.print(text);
     }
     break;
   }
   // print processing instruction
   case Node.PROCESSING_INSTRUCTION_NODE: {
     out.print("<?");
     out.print(nodeName);
     String data = node.getNodeValue();
     if (data != null && data.length() > 0) {
       out.print(" ");
       out.print(data);
     }
     out.print("?>");
     break;
   }
   // print comment
   case Node.ruMENT_NODE: {
     for (int i = 0; i < prettyIndent; i++) {
       out.print(" ");
     }
     out.print("");
     if (prettyprint) {
       out.print("\n");
     }
     break;
   }
   }
   if (type == Node.ELEMENT_NODE) {
     if (prettyprint)
       prettyIndent--;
     if (hasChildNodes == false) {
       out.print("/>");
     } else {
       if (indentEndMarker) {
         for (int i = 0; i < prettyIndent; i++) {
           out.print(" ");
         }
       }
       out.print("</");
       out.print(nodeName);
       out.print(">");
     }
     if (prettyIndent > 0) {
       out.print("\n");
     }
   }
   out.flush();
 }
 private String getNamespaceURI(String prefix, Element element, Node stopNode) {
   Node parent = element.getParentNode();
   String nsURI = element.getAttribute("xmlns:" + prefix);
   if (nsURI.length() == 0 && element != stopNode && parent instanceof Element)
     return getNamespaceURI(prefix, (Element) parent, stopNode);
   return (nsURI.length() > 0 ? nsURI : null);
 }
 private boolean isEndMarkerIndented(Node node) {
   if (prettyprint) {
     NodeList childNodes = node.getChildNodes();
     int len = childNodes.getLength();
     for (int i = 0; i < len; i++) {
       Node children = childNodes.item(i);
       if (children.getNodeType() == Node.ELEMENT_NODE) {
         return true;
       }
     }
   }
   return false;
 }
 /** Returns a sorted list of attributes. */
 private Attr[] sortAttributes(NamedNodeMap attrs) {
   int len = (attrs != null) ? attrs.getLength() : 0;
   Attr array[] = new Attr[len];
   for (int i = 0; i < len; i++) {
     array[i] = (Attr) attrs.item(i);
   }
   for (int i = 0; i < len - 1; i++) {
     String name = array[i].getNodeName();
     int index = i;
     for (int j = i + 1; j < len; j++) {
       String curName = array[j].getNodeName();
       if (curName.rupareTo(name) < 0) {
         name = curName;
         index = j;
       }
     }
     if (index != i) {
       Attr temp = array[i];
       array[i] = array[index];
       array[index] = temp;
     }
   }
   return (array);
 }
 /** Normalizes the given string. */
 public static String normalize(String s, boolean canonical) {
   StringBuffer str = new StringBuffer();
   int len = (s != null) ? s.length() : 0;
   for (int i = 0; i < len; i++) {
     char ch = s.charAt(i);
     switch (ch) {
     case "<": {
       str.append("<");
       break;
     }
     case ">": {
       str.append(">");
       break;
     }
     case "&": {
       str.append("&");
       break;
     }
     case """: {
       str.append(""");
       break;
     }
     case "\"": {
       str.append("'");
       break;
     }
     case "\r":
     case "\n": {
       if (canonical) {
         str.append("&#");
         str.append(Integer.toString(ch));
         str.append(";");
         break;
       }
       // else, default append char
     }
     default: {
       str.append(ch);
     }
     }
   }
   return (str.toString());
 }

}</source>

Traverse the DOM tree as a list

   <source lang="java">

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; 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;
   NodeIterator iterator = traversal.createNodeIterator(document.getDocumentElement(),
       NodeFilter.SHOW_ELEMENT, null, true);
   for (Node n = iterator.nextNode(); n != null; n = iterator.nextNode()) {
     System.out.println("Element: " + ((Element) n).getTagName());
   }
 }

}</source>

Traverse the DOM tree using TreeWalker

   <source lang="java">

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);
 }

}</source>

Using ranges in DOM tree

   <source lang="java">

import javax.xml.parsers.DocumentBuilder; import javax.xml.parsers.DocumentBuilderFactory; import org.w3c.dom.Document; import org.w3c.dom.Element; import org.w3c.dom.ranges.DocumentRange; import org.w3c.dom.ranges.Range; 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");
   Element order = document.getDocumentElement();
   DocumentRange ranges = (DocumentRange) document;
   Range range = ranges.createRange();
   range.setStartBefore(order.getFirstChild());
   range.setEndAfter(order.getLastChild());
   range.deleteContents();
   range.detach();
 }

}</source>