package org.pdf4j.saxon.s9api;
import org.pdf4j.saxon.Configuration;
import org.pdf4j.saxon.Controller;
import org.pdf4j.saxon.event.Receiver;
import org.pdf4j.saxon.event.TransformerReceiver;
import org.pdf4j.saxon.om.NodeInfo;
import org.pdf4j.saxon.om.ValueRepresentation;
import org.pdf4j.saxon.trans.XPathException;
import javax.xml.transform.TransformerException;
import javax.xml.transform.Source;
/**
* An <code>XsltTransformer</code> represents a compiled and loaded stylesheet ready for execution.
* The <code>XsltTransformer</code> holds details of the dynamic evaluation context for the stylesheet.
*
* <p>An <code>XsltTransformer</code> must not be used concurrently in multiple threads.
* It is safe, however, to reuse the object within a single thread to run the same
* stylesheet several times. Running the stylesheet does not change the context
* that has been established.</p>
*
* <p>An <code>XsltTransformer</code> is always constructed by running the <code>Load</code>
* method of an {@link XsltExecutable}.</p>
*
* <p>An <code>XsltTransformer</code> is itself a <code>Destination</code>. This means it is possible to use
* one <code>XsltTransformer</code> as the destination to receive the results of another transformation,
* this providing a simple way for transformations to be chained into a pipeline.</p>
* @since 9.0
*/
public class XsltTransformer implements Destination {
private Processor processor;
private Controller controller;
private NodeInfo initialContextNode;
private Destination destination;
/**
* Protected constructor
* @param processor the S9API processor
* @param controller the Saxon controller object
*/
protected XsltTransformer(Processor processor, Controller controller) {
this.processor = processor;
this.controller = controller;
}
/**
* Set the initial named template for the transformation
* @param templateName the name of the initial template, or null to indicate
* that there should be no initial named template
* @throws SaxonApiException if there is no named template with this name
*/
public void setInitialTemplate(QName templateName) throws SaxonApiException {
try {
controller.setInitialTemplate(
templateName == null ? null : templateName.getClarkName());
} catch (XPathException e) {
throw new SaxonApiException(e);
}
}
/**
* Get the initial named template for the transformation, if one has been set
* @return the name of the initial template, or null if none has been set
*/
public QName getInitialTemplate() {
String template = controller.getInitialTemplate();
return (template == null ? null : QName.fromClarkName(template));
}
/**
* Set the initial mode for the transformation
* @param modeName the name of the initial mode, or null to indicate the default
* (unnamed) mode
*/
public void setInitialMode(QName modeName) {
controller.setInitialMode(modeName == null ? null : modeName.getClarkName());
}
/**
* Get the initial mode for the transformation, if one has been set.
* @return the initial mode for the transformation. Returns null if no mode has been set,
* or if the mode was set to null to represent the default (unnamed) mode
*/
public QName getInitialMode() {
String mode = controller.getInitialMode();
if (mode == null) {
return null;
} else {
return QName.fromClarkName(mode);
}
}
/**
* Set the source document for the transformation. This method is equivalent to building
* a document from the supplied source object, and then supplying the document node of
* the resulting document as the initial context node.
* @param source the principal source document for the transformation
*/
public void setSource(Source source) throws SaxonApiException {
setInitialContextNode(processor.newDocumentBuilder().build(source));
}
/**
* Set the initial context node for the transformation.
* <p>This is ignored in the case where the {@link XsltTransformer} is used as the
* {@link Destination} of another process. In that case the initial context node will always
* be the document node of the document that is being streamed to this destination.</p>
* @param node the initial context node, or null if there is to be no initial context node
*/
public void setInitialContextNode(XdmNode node) {
initialContextNode = (node == null ? null : node.getUnderlyingNode());
}
/**
* Get the initial context node for the transformation, if one has been set
* @return the initial context node, or null if none has been set. This will not necessarily
* be the same {@link XdmNode} instance as was supplied, but it will be an XdmNode object that represents
* the same underlying node.
*/
public XdmNode getInitialContextNode() {
return (XdmNode)XdmValue.wrap(initialContextNode);
}
/**
* Set the value of a stylesheet parameter
* @param name the name of the stylesheet parameter, as a QName
* @param value the value of the stylesheet parameter, or null to clear a previously set value
*/
public void setParameter(QName name, XdmValue value) {
controller.setParameter(name.getStructuredQName(),
(value == null ? null : value.getUnderlyingValue()));
}
/**
* Get the value that has been set for a stylesheet parameter
* @param name the parameter whose name is required
* @return the value that has been set for the parameter, or null if no value has been set
*/
public XdmValue getParameter(QName name) {
Object oval = controller.getParameter(name.getClarkName());
if (oval == null) {
return null;
}
if (oval instanceof ValueRepresentation) {
return XdmValue.wrap((ValueRepresentation)oval);
}
throw new IllegalStateException(oval.getClass().getName());
}
/**
* Set the destination to be used for the transformation.
* <p>This method can be used to chain transformations into a pipeline, by using one
* {@link XsltTransformer} as the destination of another</p>
* @param destination the destination to be used
*/
public void setDestination(Destination destination) {
this.destination = destination;
}
/**
* Get the destination that was specified in a previous call of {@link #setDestination}
* @return the destination, or null if none has been supplied
*/
public Destination getDestination() {
return destination;
}
/**
* Set the MessageListener to be notified whenever the stylesheet evaluates an
* <code>xsl:message</code> instruction. If no MessageListener is nominated,
* the output of <code>xsl:message</code> instructions will be serialized and sent
* to the standard error stream.
* @param listener the MessageListener to be used
* @since 9.1
*/
public void setMessageListener(MessageListener listener) {
controller.setMessageEmitter(new MessageListenerProxy(listener));
}
/**
* Get the MessageListener to be notified whenever the stylesheet evaluates an
* <code>xsl:message</code> instruction. If no MessageListener has been nominated,
* return null
* @return the user-supplied MessageListener, or null if none has been supplied
* @since 9.1
*/
public MessageListener getMessageListener() {
Receiver r = controller.getMessageEmitter();
if (r instanceof MessageListenerProxy) {
return ((MessageListenerProxy)r).getMessageListener();
} else {
return null;
}
}
/**
* Perform the transformation. If this method is used, a destination must have been supplied
* previously
* @throws SaxonApiException if any dynamic error occurs during the transformation
* @throws IllegalStateException if no destination has been supplied
*/
public void transform() throws SaxonApiException {
if (destination == null) {
throw new IllegalStateException("No destination has been supplied");
}
try {
Receiver receiver;
if (destination instanceof Serializer) {
receiver = ((Serializer)destination).getReceiver(
controller.getConfiguration(), controller, controller.getOutputProperties());
} else {
receiver = destination.getReceiver(controller.getConfiguration());
}
controller.transform(initialContextNode, receiver);
} catch (TransformerException e) {
throw new SaxonApiException(e);
}
}
/**
* Return a Receiver which can be used to supply the principal source document for the transformation.
* This method is intended primarily for internal use, though it can also
* be called by a user application that wishes to feed events into the transformation engine.
*
* <p>Saxon calls this method to obtain a Receiver, to which it then sends
* a sequence of events representing the content of an XML document. This method is provided so that
* <code>XsltTransformer</code> implements <code>Destination</code>, allowing one transformation
* to receive the results of another in a pipeline.</p>
*
* <p>Before calling this method, the {@link #setDestination} method must be called to supply a destination
* for the transformation.</p>
*
* <p>Note that when an <code>XsltTransformer</code> is used as a <code>Destination</code>, the initial
* context node set on that <code>XsltTransformer</code> is ignored.</p>
*
* @param config The Saxon configuration. This is supplied so that the destination can
* use information from the configuration (for example, a reference to the name pool)
* to construct or configure the returned Receiver.
* @return the Receiver to which events are to be sent.
* @throws SaxonApiException if the Receiver cannot be created
* @throws IllegalStateException if no Destination has been supplied
*/
public Receiver getReceiver(Configuration config) throws SaxonApiException {
if (destination == null) {
throw new IllegalStateException("No destination has been supplied");
}
TransformerReceiver tr = new TransformerReceiver(controller);
tr.setResult(destination.getReceiver(config));
tr.setPipelineConfiguration(controller.makePipelineConfiguration());
return tr;
}
/**
* Get the underlying Controller used to implement this XsltTransformer. This provides access
* to lower-level methods not otherwise available in the s9api interface. Note that classes
* and methods obtained by this route cannot be guaranteed stable from release to release.
* @since 9.0.0.4
*/
public Controller getUnderlyingController() {
return controller;
}
}
//
// The contents of this file are subject to the Mozilla Public License Version 1.0 (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.mozilla.org/MPL/
//
// Software distributed under the License is distributed on an "AS IS" basis,
// WITHOUT WARRANTY OF ANY KIND, either express or implied.
// See the License for the specific language governing rights and limitations under the License.
//
// The Original Code is: all this file
//
// The Initial Developer of the Original Code is Michael H. Kay.
//
// Contributor(s):
//