Java Tutorial/XML/DOM Tree
Содержание
- 1 Accessing different types of DOM tree nodes
- 2 Copying a Subtree of Nodes from One DOM Document to Another
- 3 Copying a Subtree of Nodes in a DOM Document
- 4 Create new DOM tree with fully qualified element names
- 5 Creating a new DOM tree
- 6 Custom complex filters for selecting nodes
- 7 Generates a DOM from scratch. Writes the DOM to a String using an LSSerializer.
- 8 Get this Document"s root node
- 9 Print Tree node
- 10 Reading a DOM tree from XML document
- 11 Traverse a DOM tree in order to print a document that is parsed
- 12 Traverse the DOM tree as a list
- 13 Traverse the DOM tree using TreeWalker
- 14 Using ranges in DOM tree
Accessing different types of DOM tree nodes
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;
}
}
}
}
Copying a Subtree of Nodes from One DOM Document to Another
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);
}
}
Copying a Subtree of Nodes in a DOM Document
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());
}
}
Create new DOM tree with fully qualified element names
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);
}
}
Creating a new DOM tree
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);
}
}
Custom complex filters for selecting nodes
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;
}
}
}
Generates a DOM from scratch. Writes the DOM to a String using an LSSerializer.
/*
* 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();
}
}
}
Get this Document"s root node
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
}
Print Tree node
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());
}
}
}
Reading a DOM tree from XML document
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();
}
}
Traverse a DOM tree in order to print a document that is parsed
/*
*
* 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("<!--");
String data = node.getNodeValue();
if (data != null) {
out.print(data);
}
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());
}
}
Traverse the DOM tree as a list
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());
}
}
}
Traverse the DOM tree using TreeWalker
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);
}
}
Using ranges in 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.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();
}
}
