/*
============================================================================
The Apache Software License, Version 1.1
============================================================================
Copyright (C) 1999-2002 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.LexiconFactory;
import net.sourceforge.chaperon.build.LexicalAutomatonBuilder;
import net.sourceforge.chaperon.common.Decoder;
import net.sourceforge.chaperon.model.lexicon.Lexicon;
import net.sourceforge.chaperon.process.LexicalAutomaton;
import net.sourceforge.chaperon.process.PatternProcessor;
import org.apache.avalon.excalibur.pool.Recyclable;
import org.apache.avalon.framework.activity.Disposable;
import org.apache.avalon.framework.component.ComponentException;
import org.apache.avalon.framework.component.ComponentManager;
import org.apache.avalon.framework.component.Composable;
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.cocoon.ProcessingException;
import org.apache.cocoon.caching.CacheableProcessingComponent;
import org.apache.cocoon.components.source.SourceUtil;
import org.apache.cocoon.environment.SourceResolver;
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.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.AttributesImpl;
/**
* This transfomer transforms text pattern of a XML
* file into lexemes by using a lexicon file.
*
* <p>Input:</p>
* <pre>
* <section>
* Text 123 bla
* </section>
* </pre>
*
* <p>can be transformed into the following output:</p>
* <pre>
* <section>
* Text
* <lexeme symbol="number" text="123"/>
* bla
* </section>
* </pre>
*
* @author <a href="mailto:stephan@apache.org">Stephan Michels</a>
* @version CVS $Id: PatternTransformer.java,v 1.4 2003/09/05 07:10:53 cziegeler Exp $
*/
public class PatternTransformer extends AbstractTransformer
implements LogEnabled, Composable, Recyclable, Disposable, Parameterizable,
CacheableProcessingComponent {
/** Namespace for the SAX events. */
public final static String NS = "http://chaperon.sourceforge.net/schema/lexemes/1.0";
private String lexicon = null;
private Source lexiconSource = null;
private Logger logger = null;
private ComponentManager manager = null;
private SourceResolver resolver = null;
private LexicalAutomaton automaton = null;
private PatternProcessor processor = new PatternProcessor();
private boolean groups = false;
private StringBuffer buffer = new StringBuffer();
private StringBuffer output = new StringBuffer();
/**
* Provide component with a logger.
*
* @param logger the logger
*/
public void enableLogging(Logger logger) {
this.logger = logger;
}
/**
* Pass the ComponentManager to the composer. The Composable
* implementation should use the specified ComponentManager
* to acquire the components it needs for execution.
*
* @param manager The ComponentManager which this Composable uses.
*/
public void compose(ComponentManager 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 {
groups = parameters.getParameterAsBoolean("groups", false);
}
/**
* 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.lexicon = src;
this.lexiconSource = resolver.resolveURI(this.lexicon);
// Retrieve the lexical automaton from the transient store
store = (Store) this.manager.lookup(Store.TRANSIENT_STORE);
LexicalAutomatonEntry entry = (LexicalAutomatonEntry) store.get(this.lexiconSource.getURI());
// If the lexicon has changed, rebuild the lexical automaton
if ((entry==null) || (entry.getValidity()==null) ||
(entry.getValidity().isValid(this.lexiconSource.getValidity())<=
0)) {
this.logger.info("(Re)building the automaton from '"+
this.lexiconSource.getURI()+"'");
SAXConfigurationHandler confighandler = new SAXConfigurationHandler();
if (this.lexiconSource.getInputStream()==null) {
throw new ProcessingException("Source '"+
this.lexiconSource.getURI()+
"' not found");
}
SourceUtil.toSAX(this.manager, this.lexiconSource, null, confighandler);
Configuration config = confighandler.getConfiguration();
Lexicon lexicon = LexiconFactory.createLexicon(config);
LexicalAutomatonBuilder builder = new LexicalAutomatonBuilder(lexicon,
this.logger);
this.automaton = builder.getLexicalAutomaton();
this.logger.info("Store automaton into store for '"+
this.lexiconSource.getURI()+"'");
store.store(this.lexiconSource.getURI(),
new LexicalAutomatonEntry(this.automaton,
this.lexiconSource.getValidity()));
} else {
this.logger.info("Getting automaton from store for '"+
this.lexiconSource.getURI()+"'");
this.automaton = entry.getLexicalAutomaton();
}
} catch (ConfigurationException confige) {
throw new ProcessingException("Error during retrieving the lexicon",
confige);
} catch (SourceException se) {
throw new ProcessingException("Error during resolving of '"+src+
"'.", se);
} catch (ComponentException ce) {
throw new ProcessingException("Could not lookup for component",
ce);
} 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.lexiconSource.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.lexiconSource.getValidity();
}
/**
* Recycle this component.
* All instance variables are set to <code>null</code>.
*/
public void recycle() {
if ((this.resolver!=null) && (this.lexiconSource!=null)) {
this.resolver.release(this.lexiconSource);
this.lexiconSource = null;
}
this.automaton = null;
super.recycle();
}
/**
* The dispose operation is called at the end of a
* components lifecycle.
*/
public void dispose() {
if ((this.resolver!=null) && (this.lexiconSource!=null)) {
this.resolver.release(this.lexiconSource);
this.lexiconSource = null;
}
this.manager = null;
}
/**
* Receive notification of the beginning of an element.
*
* @param uri The Namespace URI, or the empty string if the element has no
* Namespace URI or if Namespace
* processing is not being performed.
* @param loc The local name (without prefix), or the empty string if
* Namespace processing is not being performed.
* @param raw The raw XML 1.0 name (with prefix), or the empty string if
* raw names are not available.
* @param a The attributes attached to the element. If there are no
* attributes, it shall be an empty Attributes object.
*
* @throws SAXException
*/
public void startElement(String uri, String loc, String raw,
Attributes a) throws SAXException {
search();
if (contentHandler!=null) {
contentHandler.startElement(uri, loc, raw, a);
}
}
/**
* Receive notification of the end of an element.
*
* @param uri The Namespace URI, or the empty string if the element has no
* Namespace URI or if Namespace
* processing is not being performed.
* @param loc The local name (without prefix), or the empty string if
* Namespace processing is not being performed.
* @param raw The raw XML 1.0 name (with prefix), or the empty string if
* raw names are not available.
*
* @throws SAXException
*/
public void endElement(String uri, String loc,
String raw) throws SAXException {
search();
if (contentHandler!=null) {
contentHandler.endElement(uri, loc, raw);
}
}
/**
* Receive notification of character data.
*
* @param c The characters from the XML document.
* @param start The start position in the array.
* @param len The number of characters to read from the array.
*
* @throws SAXException
*/
public void characters(char c[], int start, int len) throws SAXException {
buffer.append(c, start, len);
}
/**
* Receive notification of ignorable whitespace in element content.
*
* @param c The characters from the XML document.
* @param start The start position in the array.
* @param len The number of characters to read from the array.
*
* @throws SAXException
*/
public void ignorableWhitespace(char c[], int start,
int len) throws SAXException {
buffer.append(c, start, len);
}
/**
* Receive notification of a processing instruction.
*
* @param target The processing instruction target.
* @param data The processing instruction data, or null if none was
* supplied.
*
* @throws SAXException
*/
public void processingInstruction(String target,
String data) throws SAXException {
search();
if (contentHandler!=null) {
contentHandler.processingInstruction(target, data);
}
}
/**
* Report an XML comment anywhere in the document.
*
* @param ch An array holding the characters in the comment.
* @param start The starting position in the array.
* @param len The number of characters to use from the array.
*
* @throws SAXException
*/
public void comment(char ch[], int start, int len) throws SAXException {
search();
if (lexicalHandler!=null) {
lexicalHandler.comment(ch, start, len);
}
}
/**
*
*
* @throws SAXException
*/
private void search() throws SAXException {
if (buffer.length()<=0) {
return;
}
char[] text = buffer.toString().toCharArray();
String lexemesymbol, lexemetext;
String[] groups = null;
int lexemeindex = 0;
int position = 0;
output.setLength(0);
do {
lexemesymbol = null;
lexemetext = null;
for (lexemeindex = automaton.getLexemeCount()-1; lexemeindex>=0;
lexemeindex--) {
processor.setPatternAutomaton(automaton.getLexemeDefinition(lexemeindex));
if ((processor.match(text, position)) &&
((lexemetext==null) ||
(processor.getGroup().length()>=lexemetext.length()))) {
lexemesymbol = automaton.getLexemeSymbol(lexemeindex);
lexemetext = processor.getGroup();
if (this.groups) {
groups = new String[processor.getGroupCount()];
for (int group=0; group<processor.getGroupCount(); group++)
groups[group] = processor.getGroup(group);
}
}
}
if ((lexemetext!=null) && (lexemetext.length()>0)) {
if (lexemesymbol!=null) {
if (logger!=null) {
logger.debug("Recognize token "+lexemesymbol+
" with '"+Decoder.decode(lexemetext)+
"'");
}
if (output.length()>0) {
contentHandler.characters(output.toString().toCharArray(),
0, output.length());
}
output.setLength(0);
contentHandler.startPrefixMapping("", NS);
AttributesImpl atts = new AttributesImpl();
atts.addAttribute("", "symbol", "symbol", "CDATA",
lexemesymbol);
atts.addAttribute("", "text", "text", "CDATA",
lexemetext);
contentHandler.startElement(NS, "lexeme", "lexeme", atts);
if (this.groups) {
for (int group=0; group<groups.length; group++) {
contentHandler.startElement(NS, "group", "group", new AttributesImpl());
contentHandler.characters(groups[group].toCharArray(), 0, groups[group].length());
contentHandler.endElement(NS, "group", "group");
}
}
contentHandler.endElement(NS, "lexeme", "lexeme");
contentHandler.endPrefixMapping("");
} else if (logger!=null) {
logger.debug("Ignore lexeme with '"+
Decoder.decode(lexemetext)+"'");
}
position += lexemetext.length();
} else {
output.append(text[position]);
position++;
}
} while (position<text.length);
if (output.length()>0) {
contentHandler.characters(output.toString().toCharArray(), 0,
output.length());
}
buffer.setLength(0);
}
/**
* This class represent a entry in a store to cache the lexical automaton.
*/
public class LexicalAutomatonEntry implements Serializable {
private SourceValidity validity = null;
private LexicalAutomaton automaton = null;
/**
* Create a new entry.
*
* @param automaton Lexical automaton.
* @param validity Validity of the lexicon file.
*/
public LexicalAutomatonEntry(LexicalAutomaton automaton,
SourceValidity validity) {
this.automaton = automaton;
this.validity = validity;
}
/**
* Return the validity of the lexicon file.
*
* @return Validity of the lexicon file.
*/
public SourceValidity getValidity() {
return this.validity;
}
/**
* Return the lexical automaton.
*
* @return Lexical automaton.
*/
public LexicalAutomaton getLexicalAutomaton() {
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 = (LexicalAutomaton)in.readObject();
}
}
}