Working XML: Link management and preparing the future

package org.ananas.xm;
import java.io.*;
import java.util.*;
import org.xml.sax.*;
import javax.xml.transform.*;
import javax.xml.transform.sax.*;
import javax.xml.transform.stream.*;
import org.apache.xalan.serialize.*;
import org.xml.sax.ext.LexicalHandler;
import org.ananas.util.NotImplementedException;
import org.apache.xalan.templates.OutputProperties;
public class StylingMover
   extends DefaultMoverImpl
{
   protected Templates templates;
   protected long lastModified;
   protected String extension;
   protected LinkFilter linkFilter;
   protected Serializer serializer;
   public StylingMover(Messenger messenger,MoversSupervisor supervisor,File stylesheetFile)
      throws XMException
   {
      super(messenger);
      try
      {
         linkFilter = new LinkFilter(messenger,supervisor);
         lastModified = stylesheetFile.lastModified();
         templates = TransformerFactory.newInstance().newTemplates(new StreamSource(stylesheetFile));
         // right now limited to HTML formatting
         Properties properties = templates.getOutputProperties();
         extension = '.' + properties.getProperty(OutputKeys.METHOD);
         serializer = SerializerFactory.getSerializer(properties);
      }
      catch(TransformerConfigurationException e)
      {
         messenger.fatal(new XMException(e));
      }
   }
   public String getTargetName(File file)
   {
      return getDisplayName(file) + extension;
   }
   public File move(File sourceFile,File targetDir,int depth)
      throws XMException
   {
      try
      {
         File targetFile = new File(targetDir,getTargetName(sourceFile));
         if(targetFile.exists())
         {
            if(targetFile.lastModified() >= sourceFile.lastModified() &
               targetFile.lastModified() >= lastModified)
               return null;
         }
         serializer.setOutputStream(new FileOutputStream(targetFile));
         linkFilter.setDirectory(sourceFile.getParentFile(),depth);
         linkFilter.setContentHandler(serializer.asContentHandler());
         // the lexical handler is required for CDATA sections
         if(serializer instanceof LexicalHandler)
            linkFilter.setProperty("http://xml.org/sax/properties/lexical-handler",serializer);
         else
            throw new NotImplementedException("The serializer has to implements the LexicalHandler interface");
         SAXResult result = new SAXResult(linkFilter);
         Transformer transformer = templates.newTransformer();
         transformer.transform(new StreamSource(sourceFile),result);
         return targetFile;
      }
      catch(SAXException e)
      {
         messenger.error(new XMException(e));
      }
      catch(IOException e)
      {
         messenger.error(new XMException(e));
      }
      catch(TransformerException e)
      {
         messenger.error(new XMException(e));
      }
      return null;
   }
}