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////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// Copyright (c) 2018-2023 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.jaxp;
import net.sf.saxon.Configuration;
import net.sf.saxon.event.Receiver;
import net.sf.saxon.event.Sender;
import net.sf.saxon.lib.ErrorReporterToListener;
import net.sf.saxon.lib.ParseOptions;
import net.sf.saxon.lib.SerializerFactory;
import net.sf.saxon.serialize.SerializationProperties;
import net.sf.saxon.trans.XPathException;
import net.sf.saxon.trans.XmlProcessingException;
import org.xml.sax.SAXParseException;
import javax.xml.transform.*;
import java.util.Objects;
import java.util.Properties;
/**
* Saxon implementation of the JAXP IdentityTransformer.
* This is used mainly for serializing various kinds of source under
* the control of serialization parameters.
*/
public class IdentityTransformer extends Transformer {
private final Configuration configuration;
private Properties localOutputProperties;
private URIResolver uriResolver;
private ErrorListener errorListener;
protected IdentityTransformer(Configuration config) {
this.configuration = config;
}
/**
* Reset this Transformer to its original configuration.
* Transformer is reset to the same state as when it was created with
* {@link javax.xml.transform.TransformerFactory#newTransformer()},
* {@link javax.xml.transform.TransformerFactory#newTransformer(javax.xml.transform.Source source)} or
* {@link javax.xml.transform.Templates#newTransformer()}.
* reset() is designed to allow the reuse of existing Transformers
* thus saving resources associated with the creation of new Transformers.
* The reset Transformer is not guaranteed to have the same {@link javax.xml.transform.URIResolver}
* or {@link javax.xml.transform.ErrorListener} Objects, e.g. {@link Object#equals(Object obj)}.
* It is guaranteed to have a functionally equal URIResolver
* and ErrorListener.
*
* @throws UnsupportedOperationException When implementation does not
* override this method.
* @since 1.5
*/
@Override
public void reset() {
localOutputProperties = null;
uriResolver = null;
errorListener = null;
}
/**
* Set an object that will be used to resolve URIs used in
* document().
* If the resolver argument is null, the URIResolver value will
* be cleared and the transformer will no longer have a resolver.
*
* @param resolver An object that implements the URIResolver interface,
* or null.
*/
@Override
public void setURIResolver(URIResolver resolver) {
this.uriResolver = resolver;
}
/**
* Get an object that will be used to resolve URIs used in
* document().
*
* @return An object that implements the URIResolver interface,
* or null.
*/
@Override
public URIResolver getURIResolver() {
return uriResolver;
}
/**
* Set the error event listener in effect for the transformation.
*
* @param listener The new error listener.
* @throws IllegalArgumentException if listener is null.
*/
@Override
public void setErrorListener(ErrorListener listener) throws IllegalArgumentException {
this.errorListener = Objects.requireNonNull(listener);
}
/**
* Get the error event handler in effect for the transformation.
* Implementations must provide a default error listener.
*
* @return The current error handler, which should never be null.
*/
@Override
public ErrorListener getErrorListener() {
return errorListener;
}
/**
* Set the output properties for the transformation. These
* properties will override properties set in the Templates
* with xsl:output.
* If argument to this function is null, any properties
* previously set are removed, and the value will revert to the value
* defined in the templates object.
* Pass a qualified property key name as a two-part string, the namespace
* URI enclosed in curly braces ({}), followed by the local name. If the
* name has a null URL, the String only contain the local name. An
* application can safely check for a non-null URI by testing to see if the
* first character of the name is a '{' character.
* For example, if a URI and local name were obtained from an element
* defined with <xyz:foo
* xmlns:xyz="http://xyz.foo.com/yada/baz.html"/>,
* then the qualified name would be "{http://xyz.foo.com/yada/baz.html}foo".
* Note that no prefix is used.
* An IllegalArgumentException is thrown if any of the
* argument keys are not recognized and are not namespace qualified.
* As well as the properties defined in the JAXP OutputKeys class,
* Saxon defines an additional set of properties in {@link net.sf.saxon.lib.SaxonOutputKeys}.
* These fall into two categories: Constants representing serialization
* properties defined in XSLT 2.0 (which are not yet supported by JAXP),
* and constants supporting Saxon extensions to the set of serialization
* properties.
*
* @param properties A set of output properties that will be
* used to override any of the same properties in affect
* for the transformation.
* @throws IllegalArgumentException When keys are not recognized and
* are not namespace qualified.
* @see javax.xml.transform.OutputKeys
* @see java.util.Properties
*/
@Override
public void setOutputProperties(Properties properties) {
if (properties == null) {
localOutputProperties = null;
} else {
for (String key : properties.stringPropertyNames()) {
setOutputProperty(key, properties.getProperty(key));
}
}
}
/**
* Get the output properties for the transformation.
* As well as the properties defined in the JAXP OutputKeys class,
* Saxon defines an additional set of properties in {@link net.sf.saxon.lib.SaxonOutputKeys}.
* These fall into two categories: Constants representing serialization
* properties defined in XSLT 2.0 (which are not yet supported by JAXP),
* and constants supporting Saxon extensions to the set of serialization
* properties.
*
* @return the output properties being used for the transformation,
* including properties defined in the stylesheet for the unnamed
* output format
* @see net.sf.saxon.lib.SaxonOutputKeys
*/
@Override
public Properties getOutputProperties() {
// Make a copy, so that modifications to the returned properties object have no effect (even on the
// local output properties)
Properties newProps = new Properties();
Properties sheetProperties = getStylesheetOutputProperties();
for (String key : sheetProperties.stringPropertyNames()) {
newProps.setProperty(key, sheetProperties.getProperty(key));
}
if (localOutputProperties != null) {
for (String key : localOutputProperties.stringPropertyNames()) {
newProps.setProperty(key, localOutputProperties.getProperty(key));
}
}
return newProps;
}
/**
* Get the output properties defined in the stylesheet. For an identity transformer this is an empty set,
* but the method is overridden in subclasses.
*
* @return the serialization properties defined in the stylesheet, if any.
*/
protected Properties getStylesheetOutputProperties() {
return new Properties();
}
/**
* Get the local output properties held in this Transformer object, that is the properties
* explicitly requested using setOutputProperty() or setOutputProperties()
*
* @return the local output properties
*/
protected Properties getLocalOutputProperties() {
if (localOutputProperties == null) {
makeLocalOutputProperties();
}
return localOutputProperties;
}
/**
* Make the localOutputProperties object. This is a Properties object containing
* the properties set by calls on setOutputProperty or setOutputProperties; it does not include
* properties set in the stylesheet or in the configuration.
*/
private void makeLocalOutputProperties() {
localOutputProperties = new Properties();
}
/**
* Get an output property that is in effect for the transformer.
* If a property has been set using {@link #setOutputProperty},
* that value will be returned. Otherwise, if a property is explicitly
* specified in the stylesheet, that value will be returned. If
* the value of the property has been defaulted, that is, if no
* value has been set explicitly either with {@link #setOutputProperty} or
* in the stylesheet, the result may vary depending on
* implementation and input stylesheet.
*
* @param name A non-null String that specifies an output
* property name, which may be namespace qualified.
* @return The string value of the output property, or null
* if no property was found.
* @throws IllegalArgumentException If the property is not supported.
* @see javax.xml.transform.OutputKeys
*/
@Override
public String getOutputProperty(String name) throws IllegalArgumentException {
try {
getConfiguration().getSerializerFactory().checkOutputProperty(name, null);
} catch (XPathException err) {
throw new IllegalArgumentException(err.getMessage());
}
String value = null;
if (localOutputProperties != null) {
value = localOutputProperties.getProperty(name);
}
if (value == null) {
value = getStylesheetOutputProperties().getProperty(name);
}
return value;
}
/**
* Set an output property that will be in effect for the
* transformation.
* Pass a qualified property name as a two-part string, the namespace URI
* enclosed in curly braces ({}), followed by the local name. If the
* name has a null URL, the String only contain the local name. An
* application can safely check for a non-null URI by testing to see if the
* first character of the name is a '{' character.
* For example, if a URI and local name were obtained from an element
* defined with <xyz:foo
* xmlns:xyz="http://xyz.foo.com/yada/baz.html"/>,
* then the qualified name would be "{http://xyz.foo.com/yada/baz.html}foo".
* Note that no prefix is used.
* The Properties object that was passed to {@link #setOutputProperties}
* won't be effected by calling this method.
*
* @param name A non-null String that specifies an output
* property name, which may be namespace qualified.
* @param value The non-null string value of the output property.
* @throws IllegalArgumentException If the property is not supported, and is
* not qualified with a namespace.
* @see javax.xml.transform.OutputKeys
*/
@Override
public void setOutputProperty(String name, String value) throws IllegalArgumentException {
if (localOutputProperties == null) {
makeLocalOutputProperties();
}
try {
value = getConfiguration().getSerializerFactory().checkOutputProperty(name, value);
} catch (XPathException err) {
throw new IllegalArgumentException(err.getMessage());
}
localOutputProperties.setProperty(name, value);
}
/**
* Add a parameter for the transformation.
* Pass a qualified name as a two-part string, the namespace URI
* enclosed in curly braces ({}), followed by the local name. If the
* name has a null URL, the String only contain the local name. An
* application can safely check for a non-null URI by testing to see if the
* first character of the name is a '{' character.
* For example, if a URI and local name were obtained from an element
* defined with <xyz:foo
* xmlns:xyz="http://xyz.foo.com/yada/baz.html"/>,
* then the qualified name would be "{http://xyz.foo.com/yada/baz.html}foo".
* Note that no prefix is used.
*
* @param name The name of the parameter, which may begin with a
* namespace URI in curly braces ({}).
* @param value The value object. This can be any valid Java object. It is
* up to the processor to provide the proper object coersion or to simply
* pass the object on for use in an extension.
* @throws NullPointerException If value is null.
*/
@Override
public void setParameter(String name, Object value) {
// No action. Since parameters have no effect on the transformation, we ignore them
}
/**
* Get a parameter that was explicitly set with setParameter.
* This method does not return a default parameter value, which
* cannot be determined until the node context is evaluated during
* the transformation process.
*
The Saxon implementation for an IdentityTransformer always
* returns null, since parameters have no effect on an identity
* transformation.
*
* @param name of Object to get
* @return A parameter that has been set with setParameter.
*/
@Override
public Object getParameter(String name) {
return null;
}
/**
* Clear all parameters set with setParameter.
*/
@Override
public void clearParameters() {
// No action
}
/**
* Perform identify transformation from Source to Result
*/
@Override
public void transform(Source source, Result result)
throws TransformerException {
try {
SerializerFactory sf = getConfiguration().getSerializerFactory();
Receiver receiver = sf.getReceiver(result, new SerializationProperties(getOutputProperties()));
ParseOptions options = receiver.getPipelineConfiguration().getParseOptions();
if (errorListener != null) {
options = options.withErrorReporter(new ErrorReporterToListener(errorListener));
}
options = options.withContinueAfterValidationErrors(true);
Sender.send(source, receiver, options);
} catch (XPathException err) {
Throwable cause = err.getException();
if (cause instanceof SAXParseException) {
// This generally means the error was already reported.
// But if a RuntimeException occurs in Saxon during a callback from
// the Crimson parser, Crimson wraps this in a SAXParseException without
// reporting it further.
SAXParseException spe = (SAXParseException) cause;
cause = spe.getException();
if (cause instanceof RuntimeException) {
reportFatalError(err);
}
} else {
reportFatalError(err);
}
throw err;
}
}
public Configuration getConfiguration() {
return configuration;
}
protected void reportFatalError(XPathException err) {
try {
if (errorListener != null) {
errorListener.error(err);
} else {
getConfiguration().makeErrorReporter().report(new XmlProcessingException(err));
}
} catch (TransformerException e) {
// no action if error reporting fails
}
}
}