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 long lastModified;
  67                 public Templates stylesheet;
  68         };
  69
  70         public static final String SERVERNAME = "uwobo-XSLT-server";
  71         public static final String PACKAGE;
  72         public static final String VERSION;
  73         public static final String DATE;
  74         public static final String TIME;
  75         public static final String SERIALIZATION_DIR;
  76
  77         static {
  78                 Properties props = new Properties();
  79                 try {
  80                         InputStream in = Server.class.getResourceAsStream("properties.txt");
  81                         props.load(in);
  82                         in.close();
  83                 } catch (IOException ioe) {
  84                         System.err.println("Could not load the version information.");
  85                 }
  86
  87                 PACKAGE = props.getProperty("PACKAGE");
  88                 VERSION = props.getProperty("VERSION");
  89                 DATE = props.getProperty("DATE");
  90                 TIME = props.getProperty("TIME");
  91                 SERIALIZATION_DIR = props.getProperty("SERIALIZATION_DIR");
  92         }
  93
  94         Server() {
  95            if(!SERIALIZATION_DIR.equals("")) {
  96               log("Looking for serialized stylesheets");
  97               File [] serialized = new File(SERIALIZATION_DIR).listFiles();
  98               if (serialized == null) {
  99                  log("Serialized stylesheets directory \"" + SERIALIZATION_DIR +
 100                   "\" not found");
 101               } else {
 102                  for (int i = 0; i < serialized.length ; i++) {
 103                     File filename = serialized[i];
 104                     String key = filename.getName();
 105                     log("Found serialized stylesheet " + key);
 106                     log("Reloading serialized stylesheet \"" + filename + "\"... ");
 107                     FileInputStream istream;
 108                     try {
 109                        istream = new FileInputStream(filename);
 110                        ObjectInputStream p = new ObjectInputStream(istream);
 111                        Style style = (Style)p.readObject();
 112                        istream.close();
 113                        hashMap.put(key, style);
 114                     } catch (Exception e) {log(e.toString());};
 115                  }
 116                  log("Serialized stylesheets loaded!");
 117               }
 118            } else
 119               log("Stylesheet serialization is off. Set the property SERIALIZATION_DIR to a non-empty value to turn it on.");
 120
 121         }
 122
 123         private final HashMap hashMap = new HashMap();
 124         private static int logCounter = 0;
 125
 126         private final String compileStylesheet(Style style, String key) throws TransformerConfigurationException, SAXException, IOException {
 127                 StreamSource streamsource =
 128                         new StreamSource(new URL(style.fileName).openStream());
 129                 streamsource.setSystemId(style.fileName);
 130                 Templates templates =
 131                    ((SAXTransformerFactory)TransformerFactory.newInstance())
 132                       .newTemplates(streamsource);
 133                 style.stylesheet = templates;
 134                 File serializationFile = new File(SERIALIZATION_DIR,key);
 135                 String res = "";
 136                 if(!SERIALIZATION_DIR.equals("")) {
 137                    try {
 138                       FileOutputStream ostream =
 139                          new FileOutputStream(serializationFile);
 140                       ObjectOutputStream p = new ObjectOutputStream(ostream);
 141                       p.writeObject(style);
 142                       p.flush();
 143                       ostream.close();
 144                       res =
 145                        "Stylesheet serialized in \"" + serializationFile + "\"";
 146                       log(res);
 147                    } catch (FileNotFoundException e) {
 148                       res = "Warning: Stylesheet not " +
 149                          "serialized. Error opening " + "file \"" +
 150                          serializationFile + "\"";
 151                       log(res);
 152                       res = htmlOfWarning(res);
 153                    }
 154                 }
 155                 return res;
 156         }
 157
 158         private String getContentType(Templates templates) {
 159                 final Properties oprops = templates.getOutputProperties();
 160                 final String encoding = oprops.getProperty(OutputKeys.ENCODING);
 161                 final String media = oprops.getProperty(OutputKeys.MEDIA_TYPE);
 162
 163                 if (media != null) {
 164                         if (encoding != null)
 165                                 return media + "; charset=" + encoding;
 166                         return media;
 167                 } else {
 168                         final String method = oprops.getProperty(OutputKeys.METHOD);
 169                         if (method.equals("html"))
 170                                 return "text/html";
 171                         else if (method.equals("text"))
 172                                 return "text/plain";
 173                         else
 174                                 return "text/xml";
 175                 }
 176         }
 177
 178         private final ContentHandler applyStylesheet(Templates stylesheet, HashMap params, ContentHandler saxOutput)
 179         throws TransformerConfigurationException, SAXException
 180         {
 181                 TransformerHandler th = ((SAXTransformerFactory)TransformerFactory.newInstance()).newTransformerHandler(stylesheet);
 182
 183                 th.setResult(new SAXResult(saxOutput));
 184
 185                 if (params != null) {
 186                         final Transformer transformer = th.getTransformer();
 187                         Iterator i = params.keySet().iterator();
 188                         while (i.hasNext()) {
 189                                 final String name = (String) i.next();
 190                                 final String value = (String) params.get(name);
 191                                 transformer.setParameter(name, value);
 192                         }
 193                 }
 194
 195                 return th;
 196         }
 197
 198         private final void parseFile(String datasheet, ContentHandler saxOutput) throws SAXException, IOException, Exception {
 199                 final XMLReader reader = XMLReaderFactory.createXMLReader("org.apache.xerces.parsers.SAXParser");
 200                 reader.setFeature("http://xml.org/sax/features/namespaces", true);
 201                 reader.setFeature("http://xml.org/sax/features/namespace-prefixes", true);
 202                 reader.setContentHandler(saxOutput);
 203                 if (saxOutput instanceof LexicalHandler)
 204                         reader.setProperty("http://xml.org/sax/properties/lexical-handler", (LexicalHandler)saxOutput);
 205                 reader.parse(datasheet);
 206         }
 207
 208         private final ContentHandler saveFile(OutputStream outputStream, Properties props) throws IOException {
 209                 final Serializer ser = SerializerFactory.getSerializer(props);
 210                 ser.setOutputStream(outputStream);
 211                 return ser.asContentHandler();
 212         }
 213
 214         public static void log(String msg) {
 215                 System.err.println(SERVERNAME + "[" + logCounter++ + "]: " + msg);
 216         }
 217
 218         public String add(String filename, String key) throws TransformerConfigurationException, SAXException, IOException {
 219                 log("processing stylesheet \"" + filename + "\" using key " + key + "... ");
 220                 if (hashMap.containsKey(key)) {
 221                    Style style = (Style)hashMap.get(key);
 222                    if (style.fileName.equals(filename)) {
 223                       String msg =
 224                          "Warning: Stylesheet already loaded. Reloading...";
 225                       log(msg);
 226                       String msg2 = reload(key);
 227                       return htmlOfWarning(msg) +
 228                          (msg2.equals("") ? "" : "<br />" + msg2);
 229                    } else {
 230                       String res =
 231                          "Error: There is already a stylesheet with keyword \""+
 232                           key + "\" (aborted)";
 233                       log(res);
 234                       return htmlOfError(res);
 235                    }
 236                 }
 237
 238                 Style style = new Style();
 239                 style.fileName = filename;
 240                 style.lastModified = new File(filename).lastModified();
 241                 String res = compileStylesheet(style,key);
 242                 log("done!");
 243
 244                 hashMap.put(key, style);
 245                 return res;
 246         }
 247
 248         public ArrayList removeAll() throws TransformerConfigurationException, SAXException, IOException {
 249                 ArrayList res = new ArrayList();
 250                 String log = "";
 251                 Iterator i = hashMap.keySet().iterator();
 252                 while (i.hasNext()) {
 253                         String key = (String)i.next();
 254                         Style style = (Style)hashMap.get(key);
 255                         String msg =
 256                          "removing \"" + key + " (" + style.fileName + ")";
 257                         res.add(msg);
 258                         log(msg);
 259                         msg = partialRemove(key,false);
 260                         if(!msg.equals(""))
 261                            res.add(msg);
 262                 }
 263                 hashMap.clear();
 264                 return res;
 265         }
 266
 267         private String partialRemove(String key, boolean removeFromHashTable) {
 268                 String res = "";
 269                 Style style = (Style)hashMap.get(key);
 270                 if (style != null) {
 271                         log("removing \"" + key + " (" + style.fileName + ")");
 272                         if (removeFromHashTable)
 273                            hashMap.remove(key);
 274                         if(!SERIALIZATION_DIR.equals("")) {
 275                            File to_delete = new File(SERIALIZATION_DIR,key);
 276                            if (!to_delete.delete()) {
 277                               res = "Warning: Serialized stylesheet \"" +
 278                                  to_delete + "\" to remove not found";
 279                               log(res);
 280                               res = htmlOfWarning(res);
 281                            }
 282                         }
 283                 } else {
 284                         res = "Error: stylesheet \"" + key + "\" not loaded";
 285                         log(res);
 286                         res = htmlOfError(res);
 287                 }
 288                 return res;
 289         }
 290
 291         public String remove(String key) {
 292            return partialRemove(key,true);
 293         }
 294
 295         public String getContentType(String key) {
 296                 Style style = (Style)hashMap.get(key);
 297                 if (style != null) {
 298                         return getContentType(style.stylesheet);
 299                 } else {
 300                         log("Error, stylesheet \"" + key + "\" not loaded");
 301                         return null;
 302                 }
 303         }
 304
 305         public List list() {
 306                 log("listing stylesheets...");
 307                 ArrayList l = new ArrayList();
 308                 Iterator i = hashMap.keySet().iterator();
 309                 while (i.hasNext()) {
 310                         String key  = (String)i.next();
 311                         Style style = (Style)hashMap.get(key);
 312                         l.add("  " + key + " (" + style.fileName + "; " + getContentType(style.stylesheet) + ")");
 313                         System.out.println("  " + key + " (" + style.fileName + ")");
 314                 }
 315                 log("done!");
 316                 return l;
 317         }
 318
 319         private ContentHandler applyRec(final Key[] keys, int idx, final ContentHandler saxOutput)
 320         throws TransformerConfigurationException, SAXException, IOException
 321         {
 322                 if (idx < 0)
 323                         return saxOutput;
 324                 else {
 325                         final Style style = (Style) hashMap.get(keys[idx].name);
 326                         if (style == null) {
 327                                 log("cannot apply unknwon stylesheet \"" + keys[idx].name + "\" (aborted)");
 328                                 return null;
 329                         }
 330                         return applyStylesheet(style.stylesheet, keys[idx].params, applyRec(keys, idx - 1, saxOutput));
 331                 }
 332         }
 333
 334         public void apply(String inFile, OutputStream outputStream, Key[] keys, Properties userProperties)
 335         throws IOException, TransformerConfigurationException, SAXException, Exception
 336         {
 337 /*              File outFile = new File(outFilename);
 338                 if (outFile.exists())
 339                         System.out.println("Using cached version\n");
 340                 else {
 341 */
 342                         final Key[] rkeys = new Key[keys.length];
 343                         for (int i = 0; i < keys.length; i++)
 344                                 rkeys[i] = keys[keys.length - i - 1];
 345
 346                         Properties outputProperties;
 347                         Properties defaultProperties;
 348                         String method;
 349
 350                         if (keys.length > 0) {
 351                                 Style style = (Style) hashMap.get(rkeys[0].name);
 352                                 if (style == null) {
 353                                         log("Error, stylesheet \"" + rkeys[0].name + "\" not loaded");
 354                                         return;
 355                                 }
 356                                 outputProperties = style.stylesheet.getOutputProperties();
 357                                 method = userProperties.getProperty("method");
 358                                 if (method == null) method = outputProperties.getProperty("method");
 359                                 if (method == null) method = "xml";
 360                                 defaultProperties = org.apache.xalan.templates.OutputProperties.getDefaultMethodProperties(method);
 361                         } else {
 362                                 method = userProperties.getProperty("method");
 363                                 if (method == null) method = "xml";
 364                                 outputProperties = org.apache.xalan.templates.OutputProperties.getDefaultMethodProperties(method);
 365                                 defaultProperties = outputProperties;
 366                         }
 367
 368                         for (Enumeration e = userProperties.propertyNames(); e.hasMoreElements(); ) {
 369                                 String prop = (String) e.nextElement();
 370                                 String value = userProperties.getProperty(prop);
 371                                 if (value.equals("")) {
 372                                         String defaultValue = defaultProperties.getProperty(prop);
 373                                         if (defaultValue != null)
 374                                                 outputProperties.setProperty(prop, defaultProperties.getProperty(prop));
 375                                         else
 376                                                 outputProperties.remove(prop);
 377                                 } else {
 378                                         outputProperties.setProperty(prop, value);
 379                                 }
 380                         }
 381
 382                         parseFile(inFile, applyRec(rkeys, rkeys.length - 1, saveFile(outputStream, outputProperties)));
 383 //              }
 384         }
 385
 386         public ArrayList reloadAll() throws TransformerConfigurationException, SAXException, IOException {
 387                 ArrayList res = new ArrayList();
 388                 Iterator i = hashMap.keySet().iterator();
 389                 while (i.hasNext()) {
 390                         String key = (String)i.next();
 391                         Style style = (Style)hashMap.get(key);
 392                         String msg =
 393                          "reloading \"" + key + " (" + style.fileName + ")";
 394                         res.add(msg);
 395                         log(msg);
 396                         msg = reload(key);
 397                         if(!msg.equals(""))
 398                            res.add(msg);
 399                 }
 400                 return res;
 401         }
 402
 403         public String reload(String key) throws TransformerConfigurationException, SAXException, IOException {
 404                 String res = "";
 405                 Style style = (Style)hashMap.get(key);
 406                 if (style != null) {
 407                    log("reloading \"" + key + "\"... ");
 408                    style.lastModified = new File(style.fileName).lastModified();
 409                    res= compileStylesheet(style,key);
 410                    log("done!");
 411                 } else {
 412                         res = "Error: stylesheet \"" + key + "\" not loaded";
 413                         log(res);
 414                         res = htmlOfError(res);
 415                 }
 416                 return res;
 417         }
 418
 419         private String htmlOfWarning(String message)
 420         {
 421            return "<b style=\"color: maroon\">" + message+"</b>";
 422         }
 423
 424         private String htmlOfError(String message)
 425         {
 426            return "<b style=\"color: red\">" + message+"</b>";
 427         }
 428 }