//------------------------------------------------------------------------------
// Copyright (c) 2005, 2006 IBM Corporation and others.
// All rights reserved. This program and the accompanying materials
// are made available under the terms of the Eclipse Public License v1.0
// which accompanies this distribution, and is available at
// http://www.eclipse.org/legal/epl-v10.html
//
// Contributors:
// IBM Corporation - initial implementation
//------------------------------------------------------------------------------
package org.eclipse.epf.common.xml;
import java.io.ByteArrayInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileWriter;
import java.io.InputStream;
import java.io.Writer;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Properties;
import javax.xml.transform.Source;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.stream.StreamResult;
import javax.xml.transform.stream.StreamSource;
import org.eclipse.epf.common.CommonPlugin;
/**
* A wrapper over the XSLT processor bundled with the JRE.
*
* @author Kelvin Low
* @since 1.0
*/
public class XSLTProcessor {
// If true, cache the compiled the XSL transformer with the compiled XSL
// templates.
private static boolean cacheXSL;
// Caches the XSL transformers.
private static Map<String, CachedTransformer> transformerCache;
static {
String cacheXSLProperty = CommonPlugin.getDefault().getString(
"cacheXSL"); //$NON-NLS-1$
if (cacheXSLProperty != null && !cacheXSLProperty.startsWith("[")) { //$NON-NLS-1$
cacheXSL = Boolean.getBoolean(cacheXSLProperty);
} else {
cacheXSL = true;
}
if (cacheXSL) {
transformerCache = new HashMap<String, CachedTransformer>();
}
// Increase the entity expansion line limit to handle a larger number of
// XML entities.
System.setProperty("entityExpansionLimit", "1000000"); //$NON-NLS-1$ //$NON-NLS-2$
}
/**
* Default private constructor to prevent this class from being
* instantiated.
*/
private XSLTProcessor() {
}
/**
* Executes the XSL transformation given the XSL source, XML source, target
* output and encoding.
*
* @param xslSource
* The XSL source.
* @param xmlSource
* The XML source.
* @param output
* The output target.
* @param params
* The parameters for the XSL transformation.
* @param encoding
* The target encoding.
*/
public static void transform(Source xslSource, Source xmlSource,
Writer output, Properties params, String encoding) throws Exception {
if (xslSource != null && xmlSource != null) {
Transformer transformer = null;
String xslFile = xslSource.getSystemId();
if (cacheXSL && xslFile != null) {
CachedTransformer cachedTransformer = null;
synchronized (transformerCache) {
cachedTransformer = transformerCache.get(xslFile);
if (cachedTransformer == null) {
TransformerFactory factory = TransformerFactory
.newInstance();
transformer = factory.newTransformer(xslSource);
transformerCache.put(xslFile, new CachedTransformer(
transformer, params));
} else {
cachedTransformer.setParams(params);
transformer = cachedTransformer.getTransformer();
}
}
} else {
TransformerFactory factory = TransformerFactory.newInstance();
transformer = factory.newTransformer(xslSource);
if (params != null && params.size() > 0) {
for (Iterator<Object> i = params.keySet().iterator(); i
.hasNext();) {
String paramName = (String) i.next();
String paramValue = params.getProperty(paramName);
transformer.setParameter(paramName, paramValue);
}
}
}
if (encoding != null && encoding.length() > 0) {
transformer.setOutputProperty("encoding", encoding); //$NON-NLS-1$
} else {
transformer.setOutputProperty("encoding", "utf-8"); //$NON-NLS-1$ //$NON-NLS-2$
}
transformer.transform(xmlSource, new StreamResult(output));
}
}
/**
* Executes the XSL transformation given the XSL source, XML source, target
* output and encoding.
*
* @param xslSource
* The XSL source.
* @param xmlSource
* The XML source.
* @param output
* The output target.
* @param encoding
* The target encoding.
*/
public static void transform(Source xslSource, Source xmlSource,
Writer output, String encoding) throws Exception {
transform(xslSource, xmlSource, output, null, encoding);
}
/**
* Executes the XSL transformation given the XSL stylesheet URI, XML source,
* target output and encoding.
*
* @param xslURI
* The XSL stylesheet URI.
* @param xmlStr
* The XML source.
* @param output
* The output target.
* @param params
* The parameters for the XSL transformation.
* @param encoding
* The target encoding.
*/
public static void transform(String xslUri, Source xmlSource,
Writer output, Properties params, String encoding) throws Exception {
InputStream xslInput = getXslInputStream(xslUri);
if (xslInput != null) {
StreamSource xslSource = new StreamSource(xslInput);
xslSource.setSystemId(new File(xslUri));
transform(xslSource, xmlSource, output, params, encoding);
try {
xslInput.close();
} catch (Exception e) {
}
}
}
/**
* Executes the XSL transformation given the XSL stylesheet URI, XML source,
* target output and encoding.
*
* @param xslURI
* The XSL stylesheet URI.
* @param xmlStr
* The XML source.
* @param output
* The output target.
* @param encoding
* The target encoding.
*/
public static void transform(String xslUri, Source xmlSource,
Writer output, String encoding) throws Exception {
transform(xslUri, xmlSource, output, null, encoding);
}
/**
* Executes the XSL transformation given the XSL stylesheet URI, XML string,
* target output and encoding.
*
* @param xslURI
* The XSL stylesheet URI.
* @param xmlStr
* The XML string.
* @param output
* The output target.
* @param params
* The parameters for the XSL transformation.
* @param encoding
* The target encoding.
*/
public static void transform(String xslUri, String xmlStr, Writer output,
Properties params, String encoding) throws Exception {
InputStream xslInput = getXslInputStream(xslUri);
if (xslInput != null) {
StreamSource xslSource = new StreamSource(xslInput);
xslSource.setSystemId(new File(xslUri));
byte[] xml = xmlStr.getBytes("utf-8"); //$NON-NLS-1$
ByteArrayInputStream xmlInput = new ByteArrayInputStream(xml);
StreamSource xmlSource = new StreamSource(xmlInput);
transform(xslSource, xmlSource, output, params, encoding);
try {
xslInput.close();
xmlInput.close();
} catch (Exception e) {
}
}
}
/**
* Executes the XSL transformation given the XSL stylesheet URI, XML string,
* target output and encoding.
*
* @param xslURI
* The XSL stylesheet URI.
* @param xmlStr
* The XML string.
* @param output
* The output target.
* @param encoding
* The target encoding.
*/
public static void transform(String xslUri, String xmlStr, Writer output,
String encoding) throws Exception {
transform(xslUri, xmlStr, output, null, encoding);
}
/**
* Executes the XSL transformation given the XSL stylesheet URI, XML string,
* target output and encoding.
*
* @param xslURI
* The XSL stylesheet URI.
* @param xmlStr
* The XML string.
* @param file
* The output file.
* @param params
* The parameters for the XSL transformation.
* @param encoding
* The target encoding.
*/
public static void transform(String xslUri, String xmlStr, File file,
Properties params, String encoding) throws Exception {
FileWriter output = new FileWriter(file);
if (output != null) {
transform(xslUri, xmlStr, output, params, encoding);
try {
output.close();
} catch (Exception e) {
}
}
}
/**
* Executes the XSL transformation given the XSL stylesheet URI, XML string,
* target output and encoding.
*
* @param xslURI
* The XSL stylesheet URI.
* @param xmlStr
* The XML string.
* @param file
* The output file.
* @param encoding
* The target encoding.
*/
public static void transform(String xslUri, String xmlStr, File file,
String encoding) throws Exception {
transform(xslUri, xmlStr, file, null, encoding);
}
/**
* Executes the XSL transformation given the XSL stylesheet URI, XML source
* and target output.
*
* @param xslURI
* The XSL stylesheet URI.
* @param xmlStr
* The XML source.
* @param params
* The parameters for the XSL transformation.
* @param output
* The output target.
*/
public static void transform(String xslUri, Source xmlSource,
Properties params, Writer output) throws Exception {
transform(xslUri, xmlSource, output, params, null);
}
/**
* Executes the XSL transformation given the XSL stylesheet URI, XML source
* and target output.
*
* @param xslURI
* The XSL stylesheet URI.
* @param xmlStr
* The XML source.
* @param output
* The output target.
*/
public static void transform(String xslUri, Source xmlSource, Writer output)
throws Exception {
transform(xslUri, xmlSource, output, null, null);
}
/**
* Executes the XSL transformation given the XSL stylesheet URI, XML string
* and target output.
*
* @param xslURI
* The XSL stylesheet URI.
* @param xmlStr
* The XML string.
* @param params
* The parameters for the XSL transformation.
* @param output
* The output target.
*/
public static void transform(String xslUri, String xmlStr,
Properties params, Writer output) throws Exception {
transform(xslUri, xmlStr, output, params, null);
}
/**
* Executes the XSL transformation given the XSL stylesheet URI, XML string
* and target output.
*
* @param xslURI
* The XSL stylesheet URI.
* @param xmlStr
* The XML string.
* @param output
* The output target.
*/
public static void transform(String xslUri, String xmlStr, Writer output)
throws Exception {
transform(xslUri, xmlStr, output, null, null);
}
/**
* Executes the XSL transformation given the XSL stylesheet URI, XML string
* and target output file.
*
* @param xslURI
* The XSL stylesheet URI.
* @param xmlStr
* The XML string.
* @param params
* The parameters for the XSL transformation.
* @param output
* The output target.
*/
public static void transform(String xslUri, String xmlStr,
Properties params, File file) throws Exception {
transform(xslUri, xmlStr, file, params, null);
}
/**
* Executes the XSL transformation given the XSL stylesheet URI, XML string
* and target output file.
*
* @param xslURI
* The XSL stylesheet URI.
* @param xmlStr
* The XML string.
* @param output
* The output target.
*/
public static void transform(String xslUri, String xmlStr, File file)
throws Exception {
transform(xslUri, xmlStr, file, null, null);
}
/**
* Returns the XSL input stream given the XSL stylesheet URI.
*
* @param xslURI
* The XSL stylesheet URI.
*/
private static InputStream getXslInputStream(String xslUri) {
InputStream xslInput = null;
try {
xslInput = new FileInputStream(xslUri);
} catch (Exception e) {
if (xslInput == null) {
xslInput = XSLTProcessor.class.getClassLoader()
.getResourceAsStream(xslUri);
}
}
return xslInput;
}
}
/**
* A cached XSL Transformer object.
*/
class CachedTransformer {
private Transformer transformer;
private Properties params;
public CachedTransformer(Transformer transformer, Properties params) {
this.transformer = transformer;
setParams(params);
}
public Transformer getTransformer() {
return transformer;
}
public Properties getParams() {
return params;
}
public void setParams(Properties params) {
if (params != this.params) {
transformer.clearParameters();
for (Iterator<Object> i = params.keySet().iterator(); i.hasNext();) {
String paramName = (String) i.next();
String paramValue = params.getProperty(paramName);
transformer.setParameter(paramName, paramValue);
}
this.params = params;
}
}
}