/*
* JBoss, Home of Professional Open Source.
* Copyright 2008, Red Hat Middleware LLC, and individual contributors
* as indicated by the @author tags. See the copyright.txt file in the
* distribution for a full listing of individual contributors.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.jboss.varia.deployment.convertor;
import java.net.URL;
import java.util.Properties;
import java.util.Enumeration;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.IOException;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.Transformer;
import javax.xml.transform.Templates;
import javax.xml.transform.TransformerException;
import javax.xml.transform.stream.StreamSource;
import javax.xml.transform.stream.StreamResult;
/**
* XslTransformer is a utility class for XSL transformations.
*
* @author <a href="mailto:aloubyansky@hotmail.com">Alex Loubyansky</a>
*/
public class XslTransformer
{
// Attributes --------------------------------------------------------
/**
The system property that determines which Factory implementation
to create is named "javax.xml.transform.TransformerFactory".
If the property is not defined, a platform default is used.
An implementation of the TransformerFactory class is NOT guaranteed
to be thread safe.
*/
private static TransformerFactory transformerFactory =
TransformerFactory.newInstance();
// Public static methods ---------------------------------------------
/**
Applies transformation.
Pre-compiled stylesheet should be used in a thread-safe manner grabbing
a new transformer before completing the transformation.
*/
public static synchronized void applyTransformation(InputStream srcIs,
OutputStream destOs,
InputStream templateIs,
Properties outputProps)
throws TransformerException, IOException
{
StreamSource source = new StreamSource(srcIs);
StreamResult result = new StreamResult(destOs);
StreamSource template = new StreamSource(templateIs);
/*
Pre-compile the stylesheet. This Templates object may be used
concurrently across multiple threads. Creating a Templates object
allows the TransformerFactory to do detailed performance optimization
of transformation instructions, without penalizing runtime
transformation.
*/
Templates templates = transformerFactory.newTemplates( template );
Transformer transformer = templates.newTransformer();
if( outputProps != null )
{
transformer.setOutputProperties( outputProps );
}
transformer.transform( source, result );
}
/**
* Applies template <code>templateIs</code> to xml source
* <code>srcIs</code> with output properties <code>outputProps</code>
* and parameters <code>xslParams</code>.
* The resulting xml is written to <code>destOs</code>
*/
public static synchronized void applyTransformation(InputStream srcIs,
OutputStream destOs,
InputStream templateIs,
Properties outputProps,
Properties xslParams)
throws TransformerException, IOException
{
StreamSource source = new StreamSource( srcIs );
StreamResult result = new StreamResult( destOs );
StreamSource template = new StreamSource( templateIs );
Templates templates = transformerFactory.newTemplates( template );
// set output properties
Transformer transformer = templates.newTransformer();
if(outputProps != null)
{
transformer.setOutputProperties(outputProps);
}
// set xsl parameters
if(xslParams != null)
{
// note, xslParams.keys() will not work properly,
// because it will not return the keys for default properties.
Enumeration keys = xslParams.propertyNames();
while( keys.hasMoreElements() )
{
String key = (String)keys.nextElement();
transformer.setParameter(key, xslParams.getProperty(key));
}
}
transformer.transform( source, result );
}
}