/*
============================================================================
The Apache Software License, Version 1.1
============================================================================
Copyright (C) 1999-2003 The Apache Software Foundation. All rights reserved.
Redistribution and use in source and binary forms, with or without modifica-
tion, are permitted provided that the following conditions are met:
1. Redistributions of source code must retain the above copyright notice,
this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright notice,
this list of conditions and the following disclaimer in the documentation
and/or other materials provided with the distribution.
3. The end-user documentation included with the redistribution, if any, must
include the following acknowledgment: "This product includes software
developed by the Apache Software Foundation (http://www.apache.org/)."
Alternately, this acknowledgment may appear in the software itself, if
and wherever such third-party acknowledgments normally appear.
4. The names "Apache Cocoon" and "Apache Software Foundation" must not be
used to endorse or promote products derived from this software without
prior written permission. For written permission, please contact
apache@apache.org.
5. Products derived from this software may not be called "Apache", nor may
"Apache" appear in their name, without prior written permission of the
Apache Software Foundation.
THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
APACHE SOFTWARE FOUNDATION OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLU-
DING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
This software consists of voluntary contributions made by many individuals
on behalf of the Apache Software Foundation and was originally created by
Stefano Mazzocchi <stefano@apache.org>. For more information on the Apache
Software Foundation, please see <http://www.apache.org/>.
*/
package org.apache.cocoon.transformation;
import java.io.IOException;
import java.io.Serializable;
import java.util.Map;
import net.sourceforge.chaperon.adapter.avalon.GrammarFactory;
import net.sourceforge.chaperon.adapter.sax.ParserHandlerAdapter;
import net.sourceforge.chaperon.adapter.sax.ParserProcessorAdapter;
import net.sourceforge.chaperon.build.ParserAutomatonBuilder;
import net.sourceforge.chaperon.model.grammar.Grammar;
import net.sourceforge.chaperon.process.ParserAutomaton;
import net.sourceforge.chaperon.process.ParserProcessor;
import org.apache.avalon.excalibur.pool.Recyclable;
import org.apache.avalon.framework.activity.Disposable;
import org.apache.avalon.framework.configuration.Configuration;
import org.apache.avalon.framework.configuration.ConfigurationException;
import org.apache.avalon.framework.configuration.SAXConfigurationHandler;
import org.apache.avalon.framework.logger.LogEnabled;
import org.apache.avalon.framework.logger.Logger;
import org.apache.avalon.framework.parameters.ParameterException;
import org.apache.avalon.framework.parameters.Parameterizable;
import org.apache.avalon.framework.parameters.Parameters;
import org.apache.avalon.framework.service.ServiceException;
import org.apache.avalon.framework.service.ServiceManager;
import org.apache.avalon.framework.service.Serviceable;
import org.apache.cocoon.ProcessingException;
import org.apache.cocoon.caching.CacheableProcessingComponent;
import org.apache.cocoon.components.source.SourceUtil;
import org.apache.cocoon.environment.SourceResolver;
import org.apache.cocoon.xml.XMLConsumer;
import org.apache.excalibur.source.Source;
import org.apache.excalibur.source.SourceException;
import org.apache.excalibur.source.SourceValidity;
import org.apache.excalibur.store.Store;
import org.xml.sax.SAXException;
/**
* This transfomer transforms lexical tokens in a XML
* file into a XML hirachy by using a grammar file.
*
* <p>Input:</p>
* <pre>
* <lexemes xmlns="http://chaperon.sourceforge.net/schema/lexemes/1.0">
* <lexeme symbol="word" text="Text"/>
* <lexeme symbol="number" text="123"/>
* <lexeme symbol="word" text="bla"/>
* </lexemes>
* </pre>
*
* <p>were transform into the following output:</p>
* <pre>
* <sentence xmlns="http://chaperon.sourceforge.net/schema/syntaxtree/1.0">
* <word>Text</word>
* <number>123</number>
* <word>bla</word>
* </sentence>
* </pre>
*
* @author <a href="mailto:stephan@apache.org">Stephan Michels </a>
* @version CVS $Id: ParserTransformer.java,v 1.8 2003/10/25 17:55:55 cziegeler Exp $
*/
public class ParserTransformer extends ParserProcessorAdapter
implements Transformer, LogEnabled, Serviceable, Parameterizable,
Recyclable, Disposable, CacheableProcessingComponent {
private String grammar;
private Source grammarSource;
private Logger logger;
private ServiceManager manager;
private SourceResolver resolver;
private ParserAutomaton automaton;
private ParserHandlerAdapter adapter = new ParserHandlerAdapter(true);
private boolean recovery = false;
/**
* Provide component with a logger.
*
* @param logger the logger
*/
public void enableLogging(Logger logger) {
this.logger = logger;
}
/**
* Pass the ServiceManager to the Serviceable. The Serviceable
* implementation should use the specified ServiceManager
* to acquire the services it needs for execution.
*
* @param manager The ServiceManager which this Serviceable uses.
*/
public void service(ServiceManager manager) {
this.manager = manager;
}
/**
* Provide component with parameters.
*
* @param parameters the parameters
* @throws ParameterException if parameters are invalid
*/
public void parameterize(Parameters parameters)
throws ParameterException {
adapter.setFlatten(parameters.getParameterAsBoolean("flatten",
false));
recovery = parameters.getParameterAsBoolean("recovery", false);
}
/**
* Set the <code>XMLConsumer</code> that will receive XML data.
*
* @param consumer
*/
public void setConsumer(XMLConsumer consumer) {
setContentHandler(consumer);
setLexicalHandler(consumer);
adapter.setContentHandler(consumer);
}
/**
* Set the SourceResolver, objectModel Map, the source and sitemap
* Parameters used to process the request.
*
* @param resolver Source resolver
* @param objectmodel Object model
* @param src Source
* @param parameters Parameters
*
* @throws IOException
* @throws ProcessingException
* @throws SAXException
*/
public void setup(SourceResolver resolver, Map objectmodel, String src,
Parameters parameters)
throws ProcessingException, SAXException,
IOException {
this.resolver = resolver;
Store store = null;
try {
this.grammar = src;
this.grammarSource = resolver.resolveURI(this.grammar);
// Retrieve the parser automaton from the transient store
store = (Store) this.manager.lookup(Store.TRANSIENT_STORE);
ParserAutomatonEntry entry = (ParserAutomatonEntry) store.get(this.grammarSource.getURI());
// If the parser automaton has changed, rebuild the parser automaton
if ((entry==null) || (entry.getValidity()==null) ||
(entry.getValidity().isValid(this.grammarSource.getValidity()))<=
0) {
this.logger.info("(Re)building the automaton from '"+
this.grammarSource.getURI()+"'");
SAXConfigurationHandler confighandler = new SAXConfigurationHandler();
if (this.grammarSource.getInputStream()==null) {
throw new ProcessingException("Source '"+
this.grammarSource.getURI()+
"' not found");
}
SourceUtil.toSAX(this.manager, this.grammarSource, null, confighandler);
Configuration config = confighandler.getConfiguration();
Grammar grammar = GrammarFactory.createGrammar(config);
ParserAutomatonBuilder builder = new ParserAutomatonBuilder(grammar,
this.logger);
this.automaton = builder.getParserAutomaton();
this.logger.info("Store automaton into store for '"+
this.grammarSource.getURI()+"'");
store.store(this.grammarSource.getURI(),
new ParserAutomatonEntry(this.automaton,
this.grammarSource.getValidity()));
} else {
this.logger.info("Getting automaton from store for '"+
this.grammarSource.getURI()+"'");
this.automaton = entry.getParserAutomaton();
}
if (getParserProcessor()==null) {
ParserProcessor processor = new ParserProcessor();
processor.setParserHandler(this.adapter);
processor.setLogger(this.logger);
processor.setRecovery(recovery);
setParserProcessor(processor);
}
getParserProcessor().setParserAutomaton(this.automaton);
} catch (ConfigurationException confige) {
throw new ProcessingException("Error during retrieving the grammar",
confige);
} catch (SourceException se) {
throw new ProcessingException("Error during resolving of '"+src+
"'.", se);
} catch (ServiceException se) {
throw new ProcessingException("Could not lookup for component", se);
} finally {
if (store!=null) {
this.manager.release(store);
}
}
}
/**
* Generate the unique key.
* This key must be unique inside the space of this component.
*
* @return The generated key hashes the src
*/
public Serializable getKey() {
return this.grammarSource.getURI();
}
/**
* Generate the validity object.
*
* @return The generated validity object or <code>null</code> if the
* component is currently not cacheable.
*/
public SourceValidity getValidity() {
return this.grammarSource.getValidity();
}
/**
* Recycle this component.
* All instance variables are set to <code>null</code>.
*/
public void recycle() {
if ((this.resolver!=null) && (this.grammarSource!=null)) {
this.resolver.release(this.grammarSource);
this.grammarSource = null;
}
this.automaton = null;
}
/**
* The dispose operation is called at the end of a
* components lifecycle.
*/
public void dispose() {
if ((this.resolver!=null) && (this.grammarSource!=null)) {
this.resolver.release(this.grammarSource);
this.grammarSource = null;
}
this.manager = null;
}
/**
* This class represent a entry in a store to cache
* the parser automaton.
*/
public class ParserAutomatonEntry implements Serializable {
private SourceValidity validity = null;
private ParserAutomaton automaton = null;
/**
* Create a new entry.
*
* @param automaton Parser automaton.
* @param validity Validity for the grammar file.
*/
public ParserAutomatonEntry(ParserAutomaton automaton,
SourceValidity validity) {
this.automaton = automaton;
this.validity = validity;
}
/**
* Return the validity of the grammar file.
*
* @return Validity of the grammar file.
*/
public SourceValidity getValidity() {
return this.validity;
}
/**
* Return the parser automaton.
*
* @return Parser automaton.
*/
public ParserAutomaton getParserAutomaton() {
return this.automaton;
}
private void writeObject(java.io.ObjectOutputStream out)
throws IOException {
out.writeObject(validity);
out.writeObject(automaton);
}
private void readObject(java.io.ObjectInputStream in)
throws IOException, ClassNotFoundException {
validity = (SourceValidity) in.readObject();
automaton = (ParserAutomaton) in.readObject();
}
}
}