net.sf.saxon.s9api.XsltTransformer Maven / Gradle / Ivy
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////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// Copyright (c) 2013 Saxonica Limited.
// This Source Code Form is subject to the terms of the Mozilla Public License, v. 2.0.
// If a copy of the MPL was not distributed with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
// This Source Code Form is "Incompatible With Secondary Licenses", as defined by the Mozilla Public License, v. 2.0.
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
package net.sf.saxon.s9api;
import net.sf.saxon.Configuration;
import net.sf.saxon.Controller;
import net.sf.saxon.event.Builder;
import net.sf.saxon.event.Receiver;
import net.sf.saxon.lib.TraceListener;
import net.sf.saxon.om.NodeInfo;
import net.sf.saxon.om.Sequence;
import net.sf.saxon.trans.XPathException;
import javax.xml.transform.*;
import javax.xml.transform.dom.DOMSource;
import java.io.File;
import java.net.URI;
import java.net.URISyntaxException;
import java.util.Properties;
/**
* An XsltTransformer represents a compiled and loaded stylesheet ready for execution.
* The XsltTransformer holds details of the dynamic evaluation context for the stylesheet.
*
* An XsltTransformer 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.
*
* An XsltTransformer is always constructed by running the Load
* method of an {@link XsltExecutable}.
*
* An XsltTransformer is itself a Destination. This means it is possible to use
* one XsltTransformer as the destination to receive the results of another transformation,
* this providing a simple way for transformations to be chained into a pipeline. Note however that a
* when the input to a transformation is supplied in this way, it will always be built as a tree in
* memory, rather than the transformation being streamed.
*
* @since 9.0
*/
public class XsltTransformer implements Destination {
// TODO: when input is piped into an XsltTransformer, do a streamed transformation where appropriate.
private Processor processor;
private Controller controller;
/*@Nullable*/ private Source initialSource;
private Destination destination;
private Builder sourceTreeBuilder;
boolean baseOutputUriWasSet = false;
/**
* 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 name of 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.getInitialModeName();
if (mode == null) {
return null;
} else {
return QName.fromClarkName(mode);
}
}
/**
* Set the schema validation mode for the transformation. This indicates how source documents
* loaded specifically for this transformation will be handled. This applies to the
* principal source document if supplied as a SAXSource or StreamSource, and to all
* documents loaded during the transformation using the doc(), document(),
* or collection() functions.
*
* @param mode the validation mode. Passing null causes no change to the existing value.
* Passing {@link ValidationMode#DEFAULT} resets to the initial value, which determines
* the validation requirements from the Saxon Configuration.
*/
public void setSchemaValidationMode(ValidationMode mode) {
if (mode != null) {
controller.setSchemaValidationMode(mode.getNumber());
}
}
/**
* Get the schema validation mode for the transformation. This indicates how source documents
* loaded specifically for this transformation will be handled. This applies to the
* principal source document if supplied as a SAXSource or StreamSource, and to all
* documents loaded during the transformation using the doc(), document(),
* or collection() functions.
*
* @return the validation mode.
*/
public ValidationMode getSchemaValidationMode() {
return ValidationMode.get(controller.getSchemaValidationMode());
}
/**
* Set the source document for the transformation.
*
* If the source is an instance of {@link net.sf.saxon.om.NodeInfo}, the supplied node is used
* directly as the initial context item of the transformation.
*
* If the source is an instance of {@link javax.xml.transform.dom.DOMSource}, the DOM node identified
* by the DOMSource is wrapped as a Saxon node, and this is then used as the context item
*
* In other cases a new Saxon tree will be built by the transformation engine when the
* transformation starts, unless it is a Saxon-EE streaming transformation, in which case the
* document is processed in streaming fashion as it is being parsed.
*
* To run a transformation in streaming mode, the source should be supplied as an instance
* of {@link javax.xml.transform.stream.StreamSource}, {@link javax.xml.transform.sax.SAXSource},
* or {@link net.sf.saxon.event.Transmitter}.
*
* @param source the principal source document for the transformation
* @throws SaxonApiException if for example the Source is an unrecognized type of source
*/
public void setSource(Source source) throws SaxonApiException {
if (source instanceof NodeInfo) {
setInitialContextNode(new XdmNode((NodeInfo) source));
} else if (source instanceof DOMSource) {
setInitialContextNode(processor.newDocumentBuilder().wrap(source));
} else {
initialSource = source;
}
}
/**
* Set the initial context node for the transformation.
* 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.
* Calling this method has the side-effect of setting the initial source to null.
*
* @param node the initial context node, or null if there is to be no initial context node
*/
public void setInitialContextNode(XdmNode node) {
initialSource = (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() {
if (initialSource instanceof NodeInfo) {
return (XdmNode) XdmValue.wrap(((NodeInfo) initialSource));
} else {
return null;
}
}
/**
* 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 Sequence) {
return XdmValue.wrap((Sequence) oval);
}
throw new IllegalStateException(oval.getClass().getName());
}
/**
* Set the destination to be used for the result of the transformation.
* This method can be used to chain transformations into a pipeline, by using one
* {@link XsltTransformer} as the destination of another
* If the destination is a {@link Serializer}, then a side-effect of this method is to set
* the base output URI for the transformation. This acts as the base URI for resolving
* the href attribute of any xsl:result-document instruction.
* The serialiation parameters defined in the Serializer override any
* serialization parameters defined using xsl:output for the principal
* output of the transformation. However, they have no effect on any output produced
* using xsl:result-document.
*
* @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 base output URI.
*
* This defaults to the system ID of the Destination for the principal output
* of the transformation if this is known; if it is not known, it defaults
* to the current directory.
*
* If no base output URI is supplied, but the Destination of the transformation
* is a Serializer that writes to a file, then the URI of this file is used as
* the base output URI.
*
* The base output URI is used for resolving relative URIs in the href attribute
* of the xsl:result-document instruction.
*
* @param uri the base output URI
* @since 9.2
*/
public void setBaseOutputURI(String uri) {
controller.setBaseOutputURI(uri);
baseOutputUriWasSet = (uri != null);
}
/**
* Get the base output URI.
*
* This returns the value set using the {@link #setBaseOutputURI} method. If no value has been set
* explicitly, then the method returns null if called before the transformation, or the computed
* default base output URI if called after the transformation.
*
* The base output URI is used for resolving relative URIs in the href attribute
* of the xsl:result-document instruction.
*
* @return the base output URI
* @since 9.2
*/
public String getBaseOutputURI() {
return controller.getBaseOutputURI();
}
/**
* Set an object that will be used to resolve URIs used in
* fn:doc() and related functions.
*
* @param resolver An object that implements the URIResolver interface, or
* null.
* @since 9.3
*/
public void setURIResolver(URIResolver resolver) {
controller.setURIResolver(resolver);
}
/**
* Get the URI resolver.
*
* @return the user-supplied URI resolver if there is one, or null otherwise
* @since 9.3
*/
public URIResolver getURIResolver() {
return controller.getURIResolver();
}
/**
* Set the ErrorListener to be used during this transformation
*
* @param listener The error listener to be used. This is notified of all dynamic errors detected during the
* transformation.
* @since 9.2
*/
public void setErrorListener(ErrorListener listener) {
controller.setErrorListener(listener);
}
/**
* Get the ErrorListener being used during this compilation episode
*
* @return listener The error listener in use. This is notified of all dynamic errors detected during the
* transformation. If no user-supplied ErrorListener has been set the method will return a system-supplied
* ErrorListener.
* @since 9.2
*/
public ErrorListener getErrorListener() {
return controller.getErrorListener();
}
/**
* Set the MessageListener to be notified whenever the stylesheet evaluates an
* xsl:message instruction. If no MessageListener is nominated,
* the output of xsl:message 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, controller.makePipelineConfiguration()));
}
/**
* Get the MessageListener to be notified whenever the stylesheet evaluates an
* xsl:message 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;
}
}
/**
* Set a TraceListener to be notified of all events occurring during the transformation.
* This will only be effective if the stylesheet was compiled with trace code enabled
* (see {@link XsltCompiler#setCompileWithTracing(boolean)})
*
* @param listener the TraceListener to be used. Note that the TraceListener has access to
* interal Saxon interfaces which may vary from one release to the next. It is also possible that
* the TraceListener interface itself may be changed in future releases.
* @since 9.2
*/
public void setTraceListener(TraceListener listener) {
controller.setTraceListener(listener);
}
/**
* Get the TraceListener to be notified of all events occurring during the transformation.
* If no TraceListener has been nominated, return null
*
* @return the user-supplied TraceListener, or null if none has been supplied
* @since 9.2
*/
public TraceListener getTraceListener() {
return controller.getTraceListener();
}
/**
* 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");
}
if (baseOutputUriWasSet &&
destination instanceof XdmDestination &&
((XdmDestination)destination).getBaseURI() == null &&
controller.getBaseOutputURI() != null
) {
try {
((XdmDestination)destination).setBaseURI(new URI(controller.getBaseOutputURI()));
} catch (URISyntaxException e) {
// no action
}
}
try {
controller.transform(initialSource, getDestinationResult());
destination.close();
} catch (TransformerException e) {
throw new SaxonApiException(e);
}
}
private Result getDestinationResult() throws SaxonApiException {
if (destination instanceof Serializer) {
Properties props = ((Serializer) destination).getOutputProperties();
controller.setOutputProperties(props);
if (!baseOutputUriWasSet) {
Object dest = ((Serializer) destination).getOutputDestination();
if (dest instanceof File) {
controller.setBaseOutputURI(((File) dest).toURI().toString());
}
}
return ((Serializer)destination).getResult();
} else {
return destination.getReceiver(controller.getConfiguration());
}
}
/**
* 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.
*
* 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
* XsltTransformer implements Destination, allowing one transformation
* to receive the results of another in a pipeline.
*
* Before calling this method, the {@link #setDestination} method must be called to supply a destination
* for the transformation.
*
* Note that when an XsltTransformer is used as a Destination, the initial
* context node set on that XsltTransformer using {@link #setInitialContextNode(XdmNode)} is ignored,
* as is the source set using {@link #setSource(javax.xml.transform.Source)}.
*
* @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");
}
if (controller.getInitialMode().isStreamable()) {
try {
return controller.getStreamingReceiver(controller.getInitialMode(), getDestinationResult());
} catch (TransformerException e) {
throw new SaxonApiException(e);
}
} else {
sourceTreeBuilder = controller.makeBuilder();
Receiver stripper = controller.makeStripper(sourceTreeBuilder);
if (controller.getExecutable().stripsInputTypeAnnotations()) {
stripper = controller.getConfiguration().getAnnotationStripper(stripper);
}
return stripper;
}
}
/**
* Close this destination, allowing resources to be released. Used when this XsltTransformer is acting
* as the destination of another transformation. Saxon calls this method when it has finished writing
* to the destination.
*/
public void close() throws SaxonApiException {
if (sourceTreeBuilder != null) {
NodeInfo doc = sourceTreeBuilder.getCurrentRoot();
//sourceTreeBuilder.reset();
sourceTreeBuilder = null;
if (doc == null) {
throw new SaxonApiException("No source document has been built by the previous pipeline stage");
}
Result result = getDestinationResult();
try {
controller.transformDocument(doc, result);
} catch (TransformerException e) {
throw new SaxonApiException(e);
}
destination.close();
}
}
/**
* 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;
}
}