// Copyright (c) 2006 - 2008, Markus Strauch.
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
// * Redistributions of source code must retain the above copyright notice,
// this list of conditions and the following disclaimer.
// * 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.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS 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 COPYRIGHT OWNER OR 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.
package net.sf.sdedit.util;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.transform.OutputKeys;
import javax.xml.transform.Result;
import javax.xml.transform.Source;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerException;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import javax.xml.xpath.XPath;
import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathExpressionException;
import javax.xml.xpath.XPathFactory;
import org.w3c.dom.CDATASection;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
/**
*
* @author Markus Strauch
*/
public class DocUtil {
private static DocumentBuilder documentBuilder;
private static Transformer transformer;
private static XPathFactory xPathFactory = XPathFactory.newInstance();
private DocUtil() {
/* empty */
}
static {
DocumentBuilderFactory factory = null;
try {
factory = DocumentBuilderFactory.newInstance();
documentBuilder = factory.newDocumentBuilder();
transformer = TransformerFactory.newInstance().newTransformer();
factory.setIgnoringElementContentWhitespace(true);
transformer.setOutputProperty(OutputKeys.METHOD, "xml");
transformer.setOutputProperty(OutputKeys.INDENT, "yes");
} catch (Exception e) {
e.printStackTrace();
}
}
public static String evalXPathAsString(Document document, String expression)
throws XMLException {
XPath xpath = xPathFactory.newXPath();
try {
return xpath.evaluate("/extension/description", document);
} catch (XPathExpressionException xee) {
throw new XMLException("Could not evaluate XPath: " + expression,
xee);
}
}
public static String evaluateCDATA(Document document, String xPath)
throws XMLException {
StringBuffer buffer = new StringBuffer();
Element elem = (Element) evalXPathAsNode(document, xPath);
if (elem != null) {
NodeList children = elem.getChildNodes();
for (int i = 0; i < children.getLength(); i++) {
if (children.item(i) instanceof CDATASection) {
buffer.append(((CDATASection) children.item(i))
.getTextContent());
}
}
}
return buffer.toString();
}
public static Node evalXPathAsNode(Document document, String expression)
throws XMLException {
XPath xpath = xPathFactory.newXPath();
try {
Node result = (Node) xpath.evaluate(expression, document,
XPathConstants.NODE);
return result;
} catch (XPathExpressionException xee) {
throw new XMLException("Could not evaluate XPath: " + expression,
xee);
}
}
public static NodeList evalXPathAsNodeList(Document document,
String expression) throws XMLException {
XPath xpath = xPathFactory.newXPath();
try {
return (NodeList) xpath.evaluate(expression, document,
XPathConstants.NODESET);
} catch (XPathExpressionException xee) {
throw new XMLException("Could not evaluate XPath: " + expression,
xee);
}
}
/**
* Returns an empty Document.
*
* @return an empty Document
*/
public static Document newDocument() {
return documentBuilder.newDocument();
}
/**
* Writes the XML representation of a Document object.
*
* @param document
* the Document instance
* @param encoding
* the encoding to be used
* @param out
* the output stream to be used
* @throws XMLException
* @throws IOException
*/
public static void writeDocument(Document document, String encoding,
OutputStream out) throws IOException, XMLException {
OutputStreamWriter writer = new OutputStreamWriter(out, encoding);
transformer.setOutputProperty(OutputKeys.ENCODING, encoding);
Source source = new DOMSource(document);
Result result = new StreamResult(writer);
try {
transformer.transform(source, result);
} catch (TransformerException e) {
throw new XMLException("writeDocument failed", e);
}
}
/**
* Creates a Document instance from a Reader reading an XML input stream.
*
* @param in
* an XML input stream
* @return the Document object created from the XML code
* @throws IOException
* if the Reader cannot read
* @throws XMLException
*/
public static Document readDocument(InputStream in, String encoding)
throws IOException, XMLException {
InputStreamReader reader = new InputStreamReader(in, encoding);
InputSource source = new InputSource(new BufferedReader(reader));
Document document;
try {
document = documentBuilder.parse(source);
} catch (SAXException e) {
throw new XMLException("readDocument failed", e);
}
return document;
}
/**
* An <tt>XMLException</tt> is thrown when an XML document is not
* well-formed or not valid.
*/
public static class XMLException extends Exception {
/**
* Constructor.
*
* @param msg
* a descriptive message
*/
// constructors are declared private because XMLExceptions are only
// instantiated in DocUtil
private XMLException(String msg) {
super(msg);
}
/**
* Constructor.
*
* @param msg
* a descriptive message
* @param cause
* the exception causing the XMLException
*/
private XMLException(String msg, Throwable cause) {
super(msg, cause);
}
}
}