code: /*
   * 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.
   */
  /*
   * $Id$
   */
  
  
  package org.apache.xalan.xsltc.trax;
  
  import java.io.IOException;
  
  import javax.xml.XMLConstants;
  import javax.xml.parsers.FactoryConfigurationError;
  import javax.xml.parsers.ParserConfigurationException;
  import javax.xml.parsers.SAXParser;
  import javax.xml.parsers.SAXParserFactory;
  import javax.xml.transform.ErrorListener;
  import javax.xml.transform.Templates;
  import javax.xml.transform.Transformer;
  import javax.xml.transform.TransformerConfigurationException;
  import javax.xml.transform.sax.SAXResult;
  
  import org.apache.xml.utils.XMLReaderManager;
  
  import org.xml.sax.ContentHandler;
  import org.xml.sax.InputSource;
  import org.xml.sax.SAXException;
  import org.xml.sax.XMLReader;
  import org.xml.sax.helpers.XMLFilterImpl;
  import org.xml.sax.helpers.XMLReaderFactory;
  
  /**
   * skeleton extension of XMLFilterImpl for now.  
   * @author Santiago Pericas-Geertsen
   * @author G. Todd Miller 
   */
  public class TrAXFilter extends XMLFilterImpl {
      private Templates              _templates;
      private TransformerImpl	   _transformer;
      private TransformerHandlerImpl _transformerHandler;
  
      public TrAXFilter(Templates templates)  throws 
  	TransformerConfigurationException
      {
  	_templates = templates;
  	_transformer = (TransformerImpl) templates.newTransformer();
          _transformerHandler = new TransformerHandlerImpl(_transformer);
      }
      
      public Transformer getTransformer() {
          return _transformer;
      }
  
      private void createParent() throws SAXException {
  	XMLReader parent = null;
          try {
              SAXParserFactory pfactory = SAXParserFactory.newInstance();
              pfactory.setNamespaceAware(true);
              
              if (_transformer.isSecureProcessing()) {
                  try {
                      pfactory.setFeature(XMLConstants.FEATURE_SECURE_PROCESSING, true);
                  }
                  catch (SAXException e) {}
              }
              
              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
      {
          XMLReader managedReader = null;
  
          try {
              if (getParent() == null) {
                  try {
                      managedReader = XMLReaderManager.getInstance()
                                                      .getXMLReader();
                      setParent(managedReader);
                  } catch (SAXException  e) {
                      throw new SAXException(e.toString());
                  }
              }
  
              // call parse on the parent
              getParent().parse(input);
          } finally {
              if (managedReader != null) {
                  XMLReaderManager.getInstance().releaseXMLReader(managedReader);
              }
          }
      }
  
      public void parse (String systemId) throws SAXException, IOException 
      {
          parse(new InputSource(systemId));
      }
  
      public void setContentHandler (ContentHandler handler) 
      {
  	_transformerHandler.setResult(new SAXResult(handler));
  	if (getParent() == null) {
                  try {
                      createParent();
                  }
                  catch (SAXException  e) {
                     return; 
                  }
  	}
  	getParent().setContentHandler(_transformerHandler);
      }
  
      public void setErrorListener (ErrorListener handler) { }
  }
  