2 * Copyright (c) 2013 Cisco Systems, Inc. and others. All rights reserved.
4 * This program and the accompanying materials are made available under the
5 * terms of the Eclipse Public License v1.0 which accompanies this distribution,
6 * and is available at http://www.eclipse.org/legal/epl-v10.html
9 package org.opendaylight.controller.netconf.util.xml;
11 import com.google.common.base.Charsets;
12 import com.google.common.base.Optional;
13 import java.io.ByteArrayInputStream;
15 import java.io.FileInputStream;
16 import java.io.IOException;
17 import java.io.InputStream;
18 import java.io.StringWriter;
19 import javax.xml.XMLConstants;
20 import javax.xml.namespace.QName;
21 import javax.xml.parsers.DocumentBuilder;
22 import javax.xml.parsers.DocumentBuilderFactory;
23 import javax.xml.parsers.ParserConfigurationException;
24 import javax.xml.transform.OutputKeys;
25 import javax.xml.transform.Source;
26 import javax.xml.transform.Transformer;
27 import javax.xml.transform.TransformerFactory;
28 import javax.xml.transform.TransformerFactoryConfigurationError;
29 import javax.xml.transform.dom.DOMSource;
30 import javax.xml.transform.stream.StreamResult;
31 import javax.xml.transform.stream.StreamSource;
32 import javax.xml.validation.Schema;
33 import javax.xml.validation.SchemaFactory;
34 import javax.xml.xpath.XPathExpression;
35 import javax.xml.xpath.XPathExpressionException;
36 import org.opendaylight.controller.netconf.api.xml.XmlNetconfConstants;
37 import org.w3c.dom.Document;
38 import org.w3c.dom.Element;
39 import org.w3c.dom.Node;
40 import org.xml.sax.SAXException;
42 public final class XmlUtil {
44 public static final String XMLNS_ATTRIBUTE_KEY = "xmlns";
45 public static final String XMLNS_URI = "http://www.w3.org/2000/xmlns/";
46 private static final DocumentBuilderFactory BUILDER_FACTORY;
47 private static final TransformerFactory TRANSFORMER_FACTORY = TransformerFactory.newInstance();
48 private static final SchemaFactory SCHEMA_FACTORY = SchemaFactory.newInstance(XMLConstants.W3C_XML_SCHEMA_NS_URI);
51 DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
53 factory.setFeature("http://apache.org/xml/features/disallow-doctype-decl", true);
54 factory.setFeature("http://xml.org/sax/features/external-general-entities", false);
55 factory.setFeature("http://xml.org/sax/features/external-parameter-entities", false);
56 factory.setXIncludeAware(false);
57 factory.setExpandEntityReferences(false);
58 // Performance improvement for messages with size <10k according to
59 // https://xerces.apache.org/xerces2-j/faq-performance.html
60 factory.setFeature("http://apache.org/xml/features/dom/defer-node-expansion", false);
61 } catch (ParserConfigurationException e) {
62 throw new ExceptionInInitializerError(e);
64 factory.setNamespaceAware(true);
65 factory.setCoalescing(true);
66 factory.setIgnoringElementContentWhitespace(true);
67 factory.setIgnoringComments(true);
68 BUILDER_FACTORY = factory;
72 throw new UnsupportedOperationException("Utility class");
75 public static Element readXmlToElement(final String xmlContent) throws SAXException, IOException {
76 Document doc = readXmlToDocument(xmlContent);
77 return doc.getDocumentElement();
80 public static Element readXmlToElement(final InputStream xmlContent) throws SAXException, IOException {
81 Document doc = readXmlToDocument(xmlContent);
82 return doc.getDocumentElement();
85 public static Document readXmlToDocument(final String xmlContent) throws SAXException, IOException {
86 return readXmlToDocument(new ByteArrayInputStream(xmlContent.getBytes(Charsets.UTF_8)));
89 // TODO improve exceptions throwing
90 // along with XmlElement
92 public static Document readXmlToDocument(final InputStream xmlContent) throws SAXException, IOException {
93 DocumentBuilder dBuilder;
95 dBuilder = BUILDER_FACTORY.newDocumentBuilder();
96 } catch (ParserConfigurationException e) {
97 throw new IllegalStateException("Failed to parse XML document", e);
99 Document doc = dBuilder.parse(xmlContent);
101 doc.getDocumentElement().normalize();
105 public static Element readXmlToElement(final File xmlFile) throws SAXException, IOException {
106 return readXmlToDocument(new FileInputStream(xmlFile)).getDocumentElement();
109 public static Document newDocument() {
111 DocumentBuilder builder = BUILDER_FACTORY.newDocumentBuilder();
112 return builder.newDocument();
113 } catch (ParserConfigurationException e) {
114 throw new IllegalStateException("Failed to create document", e);
118 public static Element createElement(final Document document, final String qName, final Optional<String> namespaceURI) {
119 if(namespaceURI.isPresent()) {
120 final Element element = document.createElementNS(namespaceURI.get(), qName);
121 String name = XMLNS_ATTRIBUTE_KEY;
122 if(element.getPrefix() != null) {
123 name += ":" + element.getPrefix();
125 element.setAttributeNS(XMLNS_URI, name, namespaceURI.get());
128 return document.createElement(qName);
131 public static Element createTextElement(final Document document, final String qName, final String content, final Optional<String> namespaceURI) {
132 Element typeElement = createElement(document, qName, namespaceURI);
133 typeElement.appendChild(document.createTextNode(content));
137 public static Element createTextElementWithNamespacedContent(final Document document, final String qName, final String prefix,
138 final String namespace, final String contentWithoutPrefix) {
140 return createTextElementWithNamespacedContent(document, qName, prefix, namespace, contentWithoutPrefix, Optional.<String>absent());
143 public static Element createTextElementWithNamespacedContent(final Document document, final String qName, final String prefix,
144 final String namespace, final String contentWithoutPrefix, final Optional<String> namespaceURI) {
146 String content = createPrefixedValue(XmlNetconfConstants.PREFIX, contentWithoutPrefix);
147 Element element = createTextElement(document, qName, content, namespaceURI);
148 String prefixedNamespaceAttr = createPrefixedValue(XMLNS_ATTRIBUTE_KEY, prefix);
149 element.setAttributeNS(XMLNS_URI, prefixedNamespaceAttr, namespace);
153 public static String createPrefixedValue(final String prefix, final String value) {
154 return prefix + ":" + value;
157 public static String toString(final Document document) {
158 return toString(document.getDocumentElement());
161 public static String toString(final Element xml) {
162 return toString(xml, false);
165 public static String toString(final XmlElement xmlElement) {
166 return toString(xmlElement.getDomElement(), false);
169 public static String toString(final Element xml, final boolean addXmlDeclaration) {
171 Transformer transformer = TRANSFORMER_FACTORY.newTransformer();
172 transformer.setOutputProperty(OutputKeys.INDENT, "yes");
173 transformer.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, addXmlDeclaration ? "no" : "yes");
175 StreamResult result = new StreamResult(new StringWriter());
176 DOMSource source = new DOMSource(xml);
177 transformer.transform(source, result);
179 return result.getWriter().toString();
180 } catch (Exception | TransformerFactoryConfigurationError e) {
181 throw new IllegalStateException("Unable to serialize xml element " + xml, e);
185 public static String toString(final Document doc, final boolean addXmlDeclaration) {
186 return toString(doc.getDocumentElement(), addXmlDeclaration);
189 public static Schema loadSchema(final InputStream... fromStreams) {
190 Source[] sources = new Source[fromStreams.length];
192 for (InputStream stream : fromStreams) {
193 sources[i++] = new StreamSource(stream);
197 return SCHEMA_FACTORY.newSchema(sources);
198 } catch (SAXException e) {
199 throw new IllegalStateException("Failed to instantiate XML schema", e);
203 public static Object evaluateXPath(final XPathExpression expr, final Object rootNode, final QName returnType) {
205 return expr.evaluate(rootNode, returnType);
206 } catch (XPathExpressionException e) {
207 throw new IllegalStateException("Error while evaluating xpath expression " + expr, e);
211 public static Document createDocumentCopy(final Document original) {
212 final Document copiedDocument = newDocument();
213 final Node copiedRoot = copiedDocument.importNode(original.getDocumentElement(), true);
214 copiedDocument.appendChild(copiedRoot);
215 return copiedDocument;