src/org/apache/xalan/xsltc/trax/TrAXFilter.java

/*
 * @(#)$Id$
 *
 * The Apache Software License, Version 1.1
 *
 *
 * Copyright (c) 2001-2003 The Apache Software Foundation.  All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, 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 "Xalan" 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 (INCLUDING, 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 based on software copyright (c) 2001, Sun
 * Microsystems., http://www.sun.com.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 *
 * @author Santiago Pericas-Geertsen
 * @author G. Todd Miller 
 *
 */


package org.apache.xalan.xsltc.trax;

import org.xml.sax.XMLFilter;
import org.xml.sax.SAXException;
import org.xml.sax.XMLReader;
import org.xml.sax.InputSource;
import org.xml.sax.helpers.XMLFilterImpl;
import org.xml.sax.helpers.XMLReaderFactory;
import org.xml.sax.ContentHandler;
import javax.xml.transform.Templates;
import javax.xml.transform.TransformerConfigurationException;
import javax.xml.transform.ErrorListener;
import javax.xml.transform.Transformer;
import javax.xml.transform.sax.TransformerHandler;
import javax.xml.transform.sax.SAXResult;
import javax.xml.parsers.SAXParserFactory;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.FactoryConfigurationError;
import java.io.IOException;

/**
 * skeleton extension of XMLFilterImpl for now.  
 */
public class TrAXFilter extends XMLFilterImpl {
    private Templates              _templates;
    private TransformerHandlerImpl _transformer;

    public TrAXFilter(Templates templates)  throws 
	TransformerConfigurationException
    {
	_templates = templates;
        _transformer = new TransformerHandlerImpl( 
		(TransformerImpl) templates.newTransformer());
    }

    private void createParent() throws SAXException {
	XMLReader parent = null;
        try {
            SAXParserFactory pfactory = SAXParserFactory.newInstance();
            pfactory.setNamespaceAware(true);
            SAXParser saxparser = pfactory.newSAXParser();
            parent = saxparser.getXMLReader();
        }
        catch (ParserConfigurationException e) {
            throw new SAXException(e);
        }
        catch (FactoryConfigurationError e) {
            throw new SAXException(e.toString());
        }

        if (parent == null) {
            parent = XMLReaderFactory.createXMLReader();
        }

        // make this XMLReader the parent of this filter
        setParent(parent);
    }

    public void parse (InputSource input) throws SAXException, IOException
    {
	if (getParent() == null) {
		try {
		    createParent();
		}
                catch (SAXException  e) {
                    throw new SAXException(e.toString());
                }
	}

	// call parse on the parent	
	getParent().parse(input);
    }

    public void parse (String systemId) throws SAXException, IOException 
    {
        parse(new InputSource(systemId));
    }

    public void setContentHandler (ContentHandler handler) 
    {
	_transformer.setResult(new SAXResult(handler));
	if (getParent() == null) {
                try {
                    createParent();
                }
                catch (SAXException  e) {
                   return; 
                }
	}
	getParent().setContentHandler(_transformer);
    }

    public void setErrorListener (ErrorListener handler) { }
}