/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (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.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.jetspeed.rewriter.html.neko;
import java.io.Reader;
import java.io.IOException;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.xerces.xni.parser.XMLDocumentFilter;
import org.apache.xerces.xni.parser.XMLInputSource;
import org.apache.jetspeed.rewriter.ParserAdaptor;
import org.apache.jetspeed.rewriter.Rewriter;
import org.apache.jetspeed.rewriter.RewriterException;
import org.xml.sax.SAXException ;
import org.cyberneko.html.parsers.SAXParser;
import org.cyberneko.html.filters.DefaultFilter;
import org.cyberneko.html.filters.Purifier;
/**
* <p>
* NekoParserAdapter
* </p>
* <p>
*
* </p>
* @author <a href="mailto:dyoung@phase2systems.com">David L Young</a>
* @version $Id: $
*
*/
public class NekoParserAdaptor implements ParserAdaptor
{
protected final static Log log = LogFactory.getLog(NekoParserAdaptor.class);
/*
* Construct a cyberneko HTML parser adaptor
*/
public NekoParserAdaptor()
{
super();
}
/**
* <p>
* parse
* </p>
*
* @see org.apache.jetspeed.rewriter.ParserAdaptor#parse(org.apache.jetspeed.rewriter.Rewriter, java.io.Reader)
* @param rewriter
* @param reader
* @throws RewriterException
*/
public void parse(Rewriter rewriter, Reader reader)
throws RewriterException
{
// not sure what this means to parse without rewriting
rewrite(rewriter,reader,null);
}
/**
* <p>
* rewrite
* </p>
*
* @see org.apache.jetspeed.rewriter.ParserAdaptor#rewrite(org.apache.jetspeed.rewriter.Rewriter, java.io.Reader, java.io.Writer)
* @param rewriter
* @param reader
* @param writer
* @throws RewriterException
*/
public void rewrite(Rewriter rewriter, java.io.Reader reader, java.io.Writer writer)
throws RewriterException
{
// use a cyberneko SAXParser
SAXParser parser = new SAXParser() ;
// setup filter chain
XMLDocumentFilter[] filters = {
new Purifier(), // [1] standard neko purifications (tag balancing, etc)
new CallbackElementRemover( rewriter ), // [2] accept / reject tags based on advice from rewriter
writer != null ? new org.cyberneko.html.filters.Writer( writer, null ) : new DefaultFilter() // [3] propagate results to specified writer (or do nothing -- Default -- when writer is null)
};
String filtersPropName = "http://cyberneko.org/html/properties/filters";
try
{
parser.setProperty(filtersPropName, filters);
}
catch (SAXException e)
{
// either no longer supported (SAXNotSupportedException), or no logner recognized (SAXNotRecognizedException)
log.error(filtersPropName + " is, unexpectedly, no longer defined for the cyberneko HTML parser",e);
throw new RewriterException("cyberneko parser version not supported",e);
}
try
{
// parse from reader
parser.parse(new XMLInputSource( null, null, null, reader, null )) ;
}
catch (IOException e)
{
String msg = "cyberneko HTML parsing failure";
log.error(msg,e);
throw new RewriterException(msg,e);
}
}
}