/*
* 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.
*/
package org.apache.servicemix.components.xslt;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.StringWriter;
import java.net.URL;
import java.util.Iterator;
import java.util.Map;
import javax.jbi.messaging.MessageExchange;
import javax.jbi.messaging.MessagingException;
import javax.jbi.messaging.NormalizedMessage;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.transform.Result;
import javax.xml.transform.Source;
import javax.xml.transform.Templates;
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 org.apache.servicemix.MessageExchangeListener;
import org.apache.servicemix.components.util.TransformComponentSupport;
import org.apache.servicemix.jbi.jaxp.BytesSource;
import org.apache.servicemix.jbi.jaxp.SourceTransformer;
import org.apache.servicemix.jbi.jaxp.StringSource;
import org.springframework.core.io.Resource;
import org.w3c.dom.Document;
import org.w3c.dom.Node;
/**
* An <a href="http://www.w3.org/TR/xslt">XSLT</a> based JBI component using <a
* href="http://java.sun.com/xml/jaxp/">JAXP</a> to perform the XSLT
* transformation.
*
* @version $Revision: 464270 $
*/
public class XsltComponent extends TransformComponentSupport implements MessageExchangeListener {
private TransformerFactory transformerFactory;
private Source xsltSource;
private Resource xsltResource;
private Templates templates;
private boolean disableOutput;
private boolean useStringBuffer = true;
private boolean forceDocIfDom = true;
private Map xsltParameters;
/**
* @return the forceDocIfDom
*/
public boolean isForceDocIfDom() {
return forceDocIfDom;
}
/**
* @param forceDocIfDom the forceDocIfDom to set
*/
public void setForceDocIfDom(boolean forceDocIfDom) {
this.forceDocIfDom = forceDocIfDom;
}
// Properties
// -------------------------------------------------------------------------
public TransformerFactory getTransformerFactory() {
if (transformerFactory == null) {
transformerFactory = TransformerFactory.newInstance();
}
return transformerFactory;
}
public void setTransformerFactory(TransformerFactory transformerFactory) {
this.transformerFactory = transformerFactory;
}
public Source getXsltSource() throws Exception {
if (xsltSource == null) {
// lets create a new one each time
// as we can only read a stream once
xsltSource = createXsltSource();
}
return xsltSource;
}
public void setXsltSource(Source xsltSource) {
this.xsltSource = xsltSource;
}
public Resource getXsltResource() {
return xsltResource;
}
public void setXsltResource(Resource xsltResource) {
this.xsltResource = xsltResource;
}
public boolean isDisableOutput() {
return disableOutput;
}
public void setDisableOutput(boolean disableOutput) {
this.disableOutput = disableOutput;
}
public boolean isUseStringBuffer() {
return useStringBuffer;
}
public void setUseStringBuffer(boolean useStringBuffer) {
this.useStringBuffer = useStringBuffer;
}
/**
* @return the xsltParameters
*/
public Map getXsltParameters() {
return xsltParameters;
}
/**
* @param xsltParameters the xsltParameters to set
*/
public void setXsltParameters(Map xsltParameters) {
this.xsltParameters = xsltParameters;
}
// Implementation methods
// -------------------------------------------------------------------------
protected boolean transform(MessageExchange exchange, NormalizedMessage in, NormalizedMessage out)
throws MessagingException {
try {
Transformer transformer = createTransformer(exchange, in);
configureTransformer(transformer, exchange, in);
copyPropertiesAndAttachments(exchange, in, out);
transformContent(transformer, exchange, in, out);
return shouldOutputResult(transformer);
}
catch (Exception e) {
throw new MessagingException("Failed to transform: " + e, e);
}
}
protected void transformContent(Transformer transformer, MessageExchange exchange, NormalizedMessage in, NormalizedMessage out) throws TransformerException, MessagingException, ParserConfigurationException {
Source src = in.getContent();
if (forceDocIfDom && src instanceof DOMSource) {
Node n = ((DOMSource) src).getNode();
if (n instanceof Document == false) {
Document doc = DocumentBuilderFactory.newInstance().newDocumentBuilder().newDocument();
doc.appendChild(doc.importNode(n, true));
src = new DOMSource(doc);
}
}
if (isUseStringBuffer()) {
StringWriter buffer = new StringWriter();
Result result = new StreamResult(buffer);
transformer.transform(src, result);
out.setContent(new StringSource(buffer.toString()));
}
else {
ByteArrayOutputStream buffer = new ByteArrayOutputStream();
Result result = new StreamResult(buffer);
transformer.transform(src, result);
out.setContent(new BytesSource(buffer.toByteArray()));
}
}
/**
* Should we disable output of the result of the XSLT?
*/
protected boolean shouldOutputResult(Transformer transformer) {
if (disableOutput) {
return false;
}
return true;
/**
* String value = transformer.getOutputProperty("disableOutput"); return
* value == null || !value.equals("true");
*/
}
protected Source createXsltSource() throws Exception {
if (xsltResource != null) {
return new DOMSource(parse(xsltResource));
}
return null;
}
protected Document parse(Resource res) throws Exception {
URL url = null;
try {
res.getURL();
} catch (IOException e) {
// Ignore
}
DocumentBuilder builder = new SourceTransformer().createDocumentBuilder();
return builder.parse(res.getInputStream(), url != null ? url.toExternalForm() : null);
}
public Templates getTemplates() throws Exception {
if (templates == null) {
templates = createTemplates();
}
return templates;
}
/**
* Factory method to create a new transformer instance
*/
protected Templates createTemplates() throws Exception {
Source source = getXsltSource();
return getTransformerFactory().newTemplates(source);
}
/**
* Factory method to create a new transformer instance
*/
protected Transformer createTransformer(MessageExchange exchange, NormalizedMessage in)
throws Exception {
Source source = getXsltSource();
if (source == null) {
return getTransformerFactory().newTransformer();
}
else {
return getTemplates().newTransformer();
}
}
/**
* A hook to allow the transformer to be configured from the current
* exchange and inbound message
*/
protected void configureTransformer(Transformer transformer, MessageExchange exchange, NormalizedMessage in) {
for (Iterator iter = exchange.getPropertyNames().iterator(); iter.hasNext();) {
String name = (String) iter.next();
Object value = exchange.getProperty(name);
transformer.setParameter(name, value);
}
for (Iterator iter = in.getPropertyNames().iterator(); iter.hasNext();) {
String name = (String) iter.next();
Object value = in.getProperty(name);
transformer.setParameter(name, value);
}
if (xsltParameters != null) {
for (Iterator iter = xsltParameters.keySet().iterator(); iter.hasNext();) {
String name = (String) iter.next();
Object value = xsltParameters.get(name);
transformer.setParameter(name, value);
}
}
transformer.setParameter("exchange", exchange);
transformer.setParameter("in", in);
transformer.setParameter("component", this);
}
}