gomp-20050608-branch/libjava/classpath/gnu/xml/libxmlj/transform/GnomeTransformerFactory.java

   1 /* GnomeTransformerFactory.java -
   2    Copyright (C) 2004 Free Software Foundation, Inc.
   3
   4 This file is part of GNU Classpath.
   5
   6 GNU Classpath is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU Classpath is distributed in the hope that it will be useful, but
  12 WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Classpath; see the file COPYING.  If not, write to the
  18 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  19 02110-1301 USA.
  20
  21 Linking this library statically or dynamically with other modules is
  22 making a combined work based on this library.  Thus, the terms and
  23 conditions of the GNU General Public License cover the whole
  24 combination.
  25
  26 As a special exception, the copyright holders of this library give you
  27 permission to link this library with independent modules to produce an
  28 executable, regardless of the license terms of these independent
  29 modules, and to copy and distribute the resulting executable under
  30 terms of your choice, provided that you also meet, for each linked
  31 independent module, the terms and conditions of the license of that
  32 module.  An independent module is a module which is not derived from
  33 or based on this library.  If you modify this library, you may extend
  34 this exception to your version of the library, but you are not
  35 obligated to do so.  If you do not wish to do so, delete this
  36 exception statement from your version. */
  37
  38 package gnu.xml.libxmlj.transform;
  39
  40 import java.io.InputStream;
  41 import java.io.IOException;
  42 import java.util.HashMap;
  43 import java.util.Map;
  44
  45 import javax.xml.parsers.FactoryConfigurationError;
  46 import javax.xml.parsers.ParserConfigurationException;
  47 import javax.xml.parsers.SAXParser;
  48 import javax.xml.parsers.SAXParserFactory;
  49
  50 import javax.xml.transform.ErrorListener;
  51 import javax.xml.transform.Source;
  52 import javax.xml.transform.Templates;
  53 import javax.xml.transform.Transformer;
  54 import javax.xml.transform.TransformerFactory;
  55 import javax.xml.transform.TransformerConfigurationException;
  56 import javax.xml.transform.URIResolver;
  57
  58 import javax.xml.transform.dom.DOMResult;
  59 import javax.xml.transform.dom.DOMSource;
  60 import javax.xml.transform.sax.SAXSource;
  61 import javax.xml.transform.stream.StreamResult;
  62 import javax.xml.transform.stream.StreamSource;
  63
  64 import org.w3c.dom.Document;
  65 import org.w3c.dom.Node;
  66 import org.xml.sax.InputSource;
  67 import org.xml.sax.SAXException;
  68 import org.xml.sax.XMLReader;
  69 import org.xml.sax.helpers.DefaultHandler;
  70
  71 import gnu.xml.libxmlj.util.XMLJ;
  72
  73 /**
  74  *  An implementation of <code>TransformerFactory</code> producing
  75  *  <code>Transformer</code> objects which use <code>libxslt</code>
  76  *  for transformation.
  77  *
  78  *  @author Julian Scheid
  79  *  @author <a href='mailto:dog@gnu.org'>Chris Burdess</a>
  80  */
  81 public class GnomeTransformerFactory
  82   extends TransformerFactory
  83 {
  84
  85   static
  86   {
  87     XMLJ.init ();
  88   }
  89
  90   /**
  91    *  URIResolver set by user, or default implementation.
  92    */
  93   private URIResolver uriResolver;
  94
  95   /**
  96    *  ErrorListener set by user, or default implementation.
  97    */
  98   private ErrorListener errorListener;
  99
 100   /**
 101    *  Attributes set by user.
 102    */
 103   private Map attributes = new HashMap ();
 104
 105   //--- Implementation of javax.xml.transform.TransformerFactory
 106   //--- follows.
 107
 108   // -- begin getAssociatedStylesheet implementation --
 109
 110   /**
 111    * Returns the stylesheet associated with the specified XML source, or
 112    * <code>null</code> if no associated stylesheet could be found.
 113    */
 114   public Source getAssociatedStylesheet(Source source, String media,
 115                                         String title, String charset)
 116     throws TransformerConfigurationException
 117   {
 118     String href= null;
 119     String base = source.getSystemId();
 120     if (source instanceof DOMSource)
 121       {
 122         Node node = ((DOMSource) source).getNode();
 123         Document doc = (node.getNodeType() == Node.DOCUMENT_NODE) ?
 124           (Document) node : node.getOwnerDocument();
 125         if (base == null)
 126           {
 127             base = doc.getDocumentURI();
 128           }
 129         for (node = doc.getFirstChild(); node != null;
 130              node = node.getNextSibling())
 131           {
 132             if (node.getNodeType() == Node.PROCESSING_INSTRUCTION_NODE &&
 133                 "xml-stylesheet".equals(node.getNodeName()))
 134               {
 135                 String data = node.getNodeValue();
 136                 if (media != null &&
 137                     !media.equals(parseParameter(data, "type")))
 138                   {
 139                     continue;
 140                   }
 141                 if (title != null &&
 142                     !title.equals(parseParameter(data, "title")))
 143                   {
 144                     continue;
 145                   }
 146                 href = parseParameter(data, "href");
 147               }
 148           }
 149       }
 150     else
 151       {
 152         InputSource input;
 153         XMLReader parser = null;
 154         try
 155           {
 156             if (source instanceof SAXSource)
 157               {
 158                 SAXSource sax = (SAXSource) source;
 159                 input = sax.getInputSource();
 160                 parser = sax.getXMLReader();
 161               }
 162             else
 163               {
 164                 StreamSource stream = (StreamSource) source;
 165                 InputStream in = stream.getInputStream();
 166                 input = new InputSource(in);
 167               }
 168             input.setSystemId(base);
 169             if (parser == null)
 170               {
 171                 parser = createXMLReader();
 172               }
 173             AssociatedStylesheetHandler ash =
 174               new AssociatedStylesheetHandler();
 175             ash.media = media;
 176             ash.title = title;
 177             parser.setContentHandler(ash);
 178             parser.parse(input);
 179             href = ash.href;
 180           }
 181         catch (SAXException e)
 182           {
 183             throw new TransformerConfigurationException(e);
 184           }
 185         catch (IOException e)
 186           {
 187             throw new TransformerConfigurationException(e);
 188           }
 189       }
 190     if (href == null)
 191       {
 192         return null;
 193       }
 194     if (base != null)
 195       {
 196         base = XMLJ.getBaseURI(base);
 197       }
 198     href = XMLJ.getAbsoluteURI(base, href);
 199     return new StreamSource(href);
 200   }
 201
 202   private XMLReader createXMLReader()
 203     throws TransformerConfigurationException
 204   {
 205     try
 206       {
 207         SAXParserFactory factory = SAXParserFactory.newInstance();
 208         SAXParser parser = factory.newSAXParser();
 209         return parser.getXMLReader();
 210       }
 211     catch (FactoryConfigurationError e)
 212       {
 213         throw new TransformerConfigurationException(e);
 214       }
 215     catch (ParserConfigurationException e)
 216       {
 217         throw new TransformerConfigurationException(e);
 218       }
 219     catch (SAXException e)
 220       {
 221         throw new TransformerConfigurationException(e);
 222       }
 223   }
 224
 225   class AssociatedStylesheetHandler
 226     extends DefaultHandler
 227   {
 228
 229     String media;
 230     String title;
 231     String href;
 232
 233     public void processingInstruction(String target, String data)
 234       throws SAXException
 235     {
 236       if ("xml-stylesheet".equals(target))
 237         {
 238           if (media != null && !media.equals(parseParameter(data, "type")))
 239             {
 240               return;
 241             }
 242           if (title != null && !title.equals(parseParameter(data, "title")))
 243             {
 244               return;
 245             }
 246           href = parseParameter(data, "href");
 247         }
 248     }
 249
 250   }
 251
 252   String parseParameter(String data, String name)
 253   {
 254     int start = data.indexOf(name + "=");
 255     if (start != -1)
 256       {
 257         start += name.length() + 2;
 258         char delim = data.charAt(start - 1);
 259         int end = data.indexOf(delim, start);
 260         if (end != -1)
 261           {
 262             return data.substring(start, end);
 263           }
 264       }
 265     return null;
 266   }
 267
 268   // -- end getAssociatedStylesheet implementation --
 269
 270   public synchronized void setAttribute (String name, Object value)
 271   {
 272     this.attributes.put (name, value);
 273   }
 274
 275   public synchronized Object getAttribute (String name)
 276   {
 277     return attributes.get (name);
 278   }
 279
 280   public void setErrorListener (ErrorListener errorListener)
 281   {
 282     this.errorListener = errorListener;
 283   }
 284
 285   public ErrorListener getErrorListener ()
 286   {
 287     return errorListener;
 288   }
 289
 290   public void setURIResolver (URIResolver uriResolver)
 291   {
 292     this.uriResolver = uriResolver;
 293   }
 294
 295   public URIResolver getURIResolver ()
 296   {
 297     return uriResolver;
 298   }
 299
 300   public boolean getFeature (String name)
 301   {
 302     return (StreamSource.FEATURE.equals (name) ||
 303             StreamResult.FEATURE.equals (name) ||
 304             DOMSource.FEATURE.equals (name) ||
 305             DOMResult.FEATURE.equals (name));
 306   }
 307
 308   public void setFeature(String name, boolean value)
 309     throws TransformerConfigurationException
 310   {
 311     throw new TransformerConfigurationException(name);
 312   }
 313
 314   /**
 315    *  Returns a new instance of class {@link Transformer} for a
 316    *  null souce.
 317    */
 318   public Transformer newTransformer ()
 319     throws TransformerConfigurationException
 320   {
 321     return newTransformer (null);
 322   }
 323
 324   /**
 325    *  Returns a new instance of class {@link Transformer} for
 326    *  the given souce.
 327    */
 328   public Transformer newTransformer (Source source)
 329     throws TransformerConfigurationException
 330   {
 331     return new GnomeTransformer (source, uriResolver, errorListener);
 332   }
 333
 334   /**
 335    *  Returns a new instance of class {@link Templates} for
 336    *  the given souce.
 337    */
 338   public Templates newTemplates (Source source)
 339     throws TransformerConfigurationException
 340   {
 341     return new GnomeTransformer (source, uriResolver, errorListener);
 342   }
 343
 344   /**
 345    *  Perform native cleanup.
 346    */
 347   public static native void freeLibxsltGlobal ();
 348
 349 }