helm/uwobo/src/it/unibo/cs/helm/uwobo/Server.java

   1 /* Copyright (C) 2001, HELM Team
   2  *
   3  * This file is part of UWOBO, developed at the Computer Science
   4  * Department, University of Bologna, Italy.
   5  *
   6  * UWOBO is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License
   8  * as published by the Free Software Foundation; either version 2
   9  * of the License, or (at your option) any later version.
  10  *
  11  * UWOBO is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with UWOBO; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place - Suite 330, Boston,
  19  * MA  02111-1307, USA.
  20  *
  21  * For details, see the UWOBO World-Wide-Web page,
  22  * http://cs.unibo.it/helm/uwobo
  23  */
  24
  25 package it.unibo.cs.helm.uwobo;
  26
  27 import java.io.*;
  28 import java.net.URL;
  29 import java.util.*;
  30 import javax.xml.transform.*;
  31 import javax.xml.transform.sax.*;
  32 import javax.xml.transform.stream.*;
  33 import org.apache.xalan.serialize.*;
  34 import org.apache.xalan.xslt.*;
  35 import org.apache.xalan.templates.*;
  36 import org.apache.xalan.transformer.*;
  37 import org.apache.xerces.parsers.*;
  38 import org.xml.sax.*;
  39 import org.xml.sax.ext.*;
  40 import org.xml.sax.helpers.*;
  41
  42 /**
  43 // This file is part of UWOBO, a small and simple XSLT server.
  44 //
  45 // UWOBO is free software; you can redistribute it and/or
  46 // modify it under the terms of the GNU General Public License
  47 // as published by the Free Software Foundation; either version 2
  48 // of the License, or (at your option) any later version.
  49 //
  50 // UWOBO is distributed in the hope that it will be useful,
  51 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  52 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  53 // GNU General Public License for more details.
  54 //
  55 // You should have received a copy of the GNU General Public License
  56 // along with UWOBO; if not, write to the Free Software
  57 // Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  58 //
  59 // For details, send a mail to <luca.padovani@cs.unibo.it>
  60 * @author Luca Padovani, Riccardo Solmi
  61 */
  62
  63 public class Server {
  64         private static class Style implements Serializable {
  65                 public String fileName;
  66                 public Templates stylesheet;
  67         };
  68
  69         public static final String SERVERNAME = "uwobo-XSLT-server";
  70         public static final String PACKAGE;
  71         public static final String VERSION;
  72         public static final String DATE;
  73         public static final String TIME;
  74         public static final String SERIALIZATION_DIR;
  75
  76         static {
  77                 Properties props = new Properties();
  78                 try {
  79                         InputStream in = Server.class.getResourceAsStream("properties.txt");
  80                         props.load(in);
  81                         in.close();
  82                 } catch (IOException ioe) {
  83                         System.err.println("Could not load the version information.");
  84                 }
  85
  86                 PACKAGE = props.getProperty("PACKAGE");
  87                 VERSION = props.getProperty("VERSION");
  88                 DATE = props.getProperty("DATE");
  89                 TIME = props.getProperty("TIME");
  90                 SERIALIZATION_DIR = props.getProperty("SERIALIZATION_DIR");
  91         }
  92
  93         Server() {
  94            if(!SERIALIZATION_DIR.equals("")) {
  95               log("Looking for serialized stylesheets");
  96               File [] serialized = new File(SERIALIZATION_DIR).listFiles();
  97               if (serialized == null) {
  98                  log("Serialized stylesheets directory \"" + SERIALIZATION_DIR +
  99                   "\" not found");
 100               } else {
 101                  for (int i = 0; i < serialized.length ; i++) {
 102                     File filename = serialized[i];
 103                     String key = filename.getName();
 104                     log("Found serialized stylesheet " + key);
 105                     log("Reloading serialized stylesheet \"" + filename + "\"... ");
 106                     FileInputStream istream;
 107                     try {
 108                        istream = new FileInputStream(filename);
 109                        ObjectInputStream p = new ObjectInputStream(istream);
 110                        Style style = (Style)p.readObject();
 111                        istream.close();
 112                        hashMap.put(key, style);
 113                     } catch (Exception e) {log(e.toString());};
 114                  }
 115                  log("Serialized stylesheets loaded!");
 116               }
 117            } else
 118               log("Stylesheet serialization is off. Set the property SERIALIZATION_DIR to a non-empty value to turn it on.");
 119
 120         }
 121
 122         private final HashMap hashMap = new HashMap();
 123         private static int logCounter = 0;
 124
 125         private final String compileStylesheet(Style style, String key) throws TransformerConfigurationException, SAXException, IOException {
 126                 StreamSource streamsource =
 127                         new StreamSource(new URL(style.fileName).openStream());
 128                 streamsource.setSystemId(style.fileName);
 129                 Templates templates =
 130                    ((SAXTransformerFactory)TransformerFactory.newInstance())
 131                       .newTemplates(streamsource);
 132                 style.stylesheet = templates;
 133                 File serializationFile = new File(SERIALIZATION_DIR,key);
 134                 String res = "";
 135                 if(!SERIALIZATION_DIR.equals("")) {
 136                    try {
 137                       FileOutputStream ostream =
 138                          new FileOutputStream(serializationFile);
 139                       ObjectOutputStream p = new ObjectOutputStream(ostream);
 140                       p.writeObject(style);
 141                       p.flush();
 142                       ostream.close();
 143                       res =
 144                        "Stylesheet serialized in \"" + serializationFile + "\"";
 145                       log(res);
 146                    } catch (FileNotFoundException e) {
 147                       res = "Warning: Stylesheet not " +
 148                          "serialized. Error opening " + "file \"" +
 149                          serializationFile + "\"";
 150                       log(res);
 151                       res = htmlOfWarning(res);
 152                    }
 153                 }
 154                 return res;
 155         }
 156
 157         private String getContentType(Templates templates) {
 158                 final Properties oprops = templates.getOutputProperties();
 159                 final String encoding = oprops.getProperty(OutputKeys.ENCODING);
 160                 final String media = oprops.getProperty(OutputKeys.MEDIA_TYPE);
 161
 162                 if (media != null) {
 163                         if (encoding != null)
 164                                 return media + "; charset=" + encoding;
 165                         return media;
 166                 } else {
 167                         final String method = oprops.getProperty(OutputKeys.METHOD);
 168                         if (method.equals("html"))
 169                                 return "text/html";
 170                         else if (method.equals("text"))
 171                                 return "text/plain";
 172                         else
 173                                 return "text/xml";
 174                 }
 175         }
 176
 177         private final ContentHandler applyStylesheet(Templates stylesheet, HashMap params, ContentHandler saxOutput)
 178         throws TransformerConfigurationException, SAXException
 179         {
 180                 TransformerHandler th = ((SAXTransformerFactory)TransformerFactory.newInstance()).newTransformerHandler(stylesheet);
 181
 182                 th.setResult(new SAXResult(saxOutput));
 183
 184                 if (params != null) {
 185                         final Transformer transformer = th.getTransformer();
 186                         Iterator i = params.keySet().iterator();
 187                         while (i.hasNext()) {
 188                                 final String name = (String) i.next();
 189                                 final String value = (String) params.get(name);
 190                                 transformer.setParameter(name, value);
 191                         }
 192                 }
 193
 194                 return th;
 195         }
 196
 197         private final void parseFile(String datasheet, ContentHandler saxOutput) throws SAXException, IOException, Exception {
 198                 final XMLReader reader = XMLReaderFactory.createXMLReader("org.apache.xerces.parsers.SAXParser");
 199                 reader.setFeature("http://xml.org/sax/features/namespaces", true);
 200                 reader.setFeature("http://xml.org/sax/features/namespace-prefixes", true);
 201                 reader.setContentHandler(saxOutput);
 202                 if (saxOutput instanceof LexicalHandler)
 203                         reader.setProperty("http://xml.org/sax/properties/lexical-handler", (LexicalHandler)saxOutput);
 204                 reader.parse(datasheet);
 205         }
 206
 207         private final ContentHandler saveFile(OutputStream outputStream, Properties props) throws IOException {
 208                 final Serializer ser = SerializerFactory.getSerializer(props);
 209                 ser.setOutputStream(outputStream);
 210                 return ser.asContentHandler();
 211         }
 212
 213         public static void log(String msg) {
 214                 System.err.println(SERVERNAME + "[" + logCounter++ + "]: " + msg);
 215         }
 216
 217         public String add(String filename, String key) throws TransformerConfigurationException, SAXException, IOException {
 218                 log("processing stylesheet \"" + filename + "\" using key " + key + "... ");
 219                 if (hashMap.containsKey(key)) {
 220                    Style style = (Style)hashMap.get(key);
 221                    if (style.fileName.equals(filename)) {
 222                       String msg =
 223                          "Warning: Stylesheet already loaded. Request ignored.";
 224                       log(msg);
 225                       return htmlOfWarning(msg);
 226                    } else {
 227                       String res =
 228                          "Error: There is already a stylesheet with keyword \""+
 229                           key + "\" (aborted)";
 230                       log(res);
 231                       return htmlOfError(res);
 232                    }
 233                 }
 234
 235                 Style style = new Style();
 236                 style.fileName = filename;
 237                 String res = compileStylesheet(style,key);
 238                 log("done!");
 239
 240                 hashMap.put(key, style);
 241                 return res;
 242         }
 243
 244         public ArrayList removeAll() throws TransformerConfigurationException, SAXException, IOException {
 245                 ArrayList res = new ArrayList();
 246                 String log = "";
 247                 Iterator i = hashMap.keySet().iterator();
 248                 while (i.hasNext()) {
 249                         String key = (String)i.next();
 250                         Style style = (Style)hashMap.get(key);
 251                         String msg =
 252                          "removing \"" + key + " (" + style.fileName + ")";
 253                         res.add(msg);
 254                         log(msg);
 255                         msg = partialRemove(key,false);
 256                         if(!msg.equals(""))
 257                            res.add(msg);
 258                 }
 259                 hashMap.clear();
 260                 return res;
 261         }
 262
 263         private String partialRemove(String key, boolean removeFromHashTable) {
 264                 String res = "";
 265                 Style style = (Style)hashMap.get(key);
 266                 if (style != null) {
 267                         log("removing \"" + key + " (" + style.fileName + ")");
 268                         if (removeFromHashTable)
 269                            hashMap.remove(key);
 270                         if(!SERIALIZATION_DIR.equals("")) {
 271                            File to_delete = new File(SERIALIZATION_DIR,key);
 272                            if (!to_delete.delete()) {
 273                               res = "Warning: Serialized stylesheet \"" +
 274                                  to_delete + "\" to remove not found";
 275                               log(res);
 276                               res = htmlOfWarning(res);
 277                            }
 278                         }
 279                 } else {
 280                         res = "Error: stylesheet \"" + key + "\" not loaded";
 281                         log(res);
 282                         res = htmlOfError(res);
 283                 }
 284                 return res;
 285         }
 286
 287         public String remove(String key) {
 288            return partialRemove(key,true);
 289         }
 290
 291         public String getContentType(String key) {
 292                 Style style = (Style)hashMap.get(key);
 293                 if (style != null) {
 294                         return getContentType(style.stylesheet);
 295                 } else {
 296                         log("Error, stylesheet \"" + key + "\" not loaded");
 297                         return null;
 298                 }
 299         }
 300
 301         public List list() {
 302                 log("listing stylesheets...");
 303                 ArrayList l = new ArrayList();
 304                 Iterator i = hashMap.keySet().iterator();
 305                 while (i.hasNext()) {
 306                         String key  = (String)i.next();
 307                         Style style = (Style)hashMap.get(key);
 308                         l.add("  " + key + " (" + style.fileName + "; " + getContentType(style.stylesheet) + ")");
 309                         System.out.println("  " + key + " (" + style.fileName + ")");
 310                 }
 311                 log("done!");
 312                 return l;
 313         }
 314
 315         private ContentHandler applyRec(final Key[] keys, int idx, final ContentHandler saxOutput)
 316         throws TransformerConfigurationException, SAXException, IOException
 317         {
 318                 if (idx < 0)
 319                         return saxOutput;
 320                 else {
 321                         final Style style = (Style) hashMap.get(keys[idx].name);
 322                         if (style == null) {
 323                                 log("cannot apply unknwon stylesheet \"" + keys[idx].name + "\" (aborted)");
 324                                 return null;
 325                         }
 326                         return applyStylesheet(style.stylesheet, keys[idx].params, applyRec(keys, idx - 1, saxOutput));
 327                 }
 328         }
 329
 330         public void apply(String inFile, OutputStream outputStream, Key[] keys, Properties userProperties)
 331         throws IOException, TransformerConfigurationException, SAXException, Exception
 332         {
 333 /*              File outFile = new File(outFilename);
 334                 if (outFile.exists())
 335                         System.out.println("Using cached version\n");
 336                 else {
 337 */
 338                         final Key[] rkeys = new Key[keys.length];
 339                         for (int i = 0; i < keys.length; i++)
 340                                 rkeys[i] = keys[keys.length - i - 1];
 341
 342                         Properties outputProperties;
 343                         Properties defaultProperties;
 344                         String method;
 345
 346                         if (keys.length > 0) {
 347                                 Style style = (Style) hashMap.get(rkeys[0].name);
 348                                 if (style == null) {
 349                                         log("Error, stylesheet \"" + rkeys[0].name + "\" not loaded");
 350                                         return;
 351                                 }
 352                                 outputProperties = style.stylesheet.getOutputProperties();
 353                                 method = userProperties.getProperty("method");
 354                                 if (method == null) method = outputProperties.getProperty("method");
 355                                 if (method == null) method = "xml";
 356                                 defaultProperties = org.apache.xalan.templates.OutputProperties.getDefaultMethodProperties(method);
 357                         } else {
 358                                 method = userProperties.getProperty("method");
 359                                 if (method == null) method = "xml";
 360                                 outputProperties = org.apache.xalan.templates.OutputProperties.getDefaultMethodProperties(method);
 361                                 defaultProperties = outputProperties;
 362                         }
 363
 364                         for (Enumeration e = userProperties.propertyNames(); e.hasMoreElements(); ) {
 365                                 String prop = (String) e.nextElement();
 366                                 String value = userProperties.getProperty(prop);
 367                                 if (value.equals("")) {
 368                                         String defaultValue = defaultProperties.getProperty(prop);
 369                                         if (defaultValue != null)
 370                                                 outputProperties.setProperty(prop, defaultProperties.getProperty(prop));
 371                                         else
 372                                                 outputProperties.remove(prop);
 373                                 } else {
 374                                         outputProperties.setProperty(prop, value);
 375                                 }
 376                         }
 377
 378                         parseFile(inFile, applyRec(rkeys, rkeys.length - 1, saveFile(outputStream, outputProperties)));
 379 //              }
 380         }
 381
 382         public ArrayList reloadAll() throws TransformerConfigurationException, SAXException, IOException {
 383                 ArrayList res = new ArrayList();
 384                 Iterator i = hashMap.keySet().iterator();
 385                 while (i.hasNext()) {
 386                         String key = (String)i.next();
 387                         Style style = (Style)hashMap.get(key);
 388                         String msg =
 389                          "reloading \"" + key + " (" + style.fileName + ")";
 390                         res.add(msg);
 391                         log(msg);
 392                         msg = reload(key);
 393                         if(!msg.equals(""))
 394                            res.add(msg);
 395                 }
 396                 return res;
 397         }
 398
 399         public String reload(String key) throws TransformerConfigurationException, SAXException, IOException {
 400                 String res = "";
 401                 Style style = (Style)hashMap.get(key);
 402                 if (style != null) {
 403                    log("reloading \"" + key + "\"... ");
 404                    res= compileStylesheet(style,key);
 405                    log("done!");
 406                 } else {
 407                         res = "Error: stylesheet \"" + key + "\" not loaded";
 408                         log(res);
 409                         res = htmlOfError(res);
 410                 }
 411                 return res;
 412         }
 413
 414         private String htmlOfWarning(String message)
 415         {
 416            return "<b style=\"color: maroon\">" + message+"</b>";
 417         }
 418
 419         private String htmlOfError(String message)
 420         {
 421            return "<b style=\"color: red\">" + message+"</b>";
 422         }
 423 }