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

   1 package it.unibo.cs.helm.uwobo;
   2
   3 import java.io.*;
   4 import java.net.URL;
   5 import java.util.*;
   6 import javax.xml.transform.*;
   7 import javax.xml.transform.sax.*;
   8 import javax.xml.transform.stream.*;
   9 import org.apache.xalan.serialize.*;
  10 import org.apache.xalan.xslt.*;
  11 import org.apache.xalan.templates.*;
  12 import org.apache.xalan.transformer.*;
  13 import org.apache.xerces.parsers.*;
  14 import org.xml.sax.*;
  15 import org.xml.sax.ext.*;
  16 import org.xml.sax.helpers.*;
  17
  18 /**
  19 // This file is part of UWOBO, a small and simple XSLT server.
  20 //
  21 // UWOBO is free software; you can redistribute it and/or
  22 // modify it under the terms of the GNU General Public License
  23 // as published by the Free Software Foundation; either version 2
  24 // of the License, or (at your option) any later version.
  25 //
  26 // UWOBO is distributed in the hope that it will be useful,
  27 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  28 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  29 // GNU General Public License for more details.
  30 //
  31 // You should have received a copy of the GNU General Public License
  32 // along with UWOBO; if not, write to the Free Software
  33 // Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  34 //
  35 // For details, send a mail to <luca.padovani@cs.unibo.it>
  36 * @author Luca Padovani, Riccardo Solmi
  37 */
  38
  39 public class Server {
  40         private static class Style implements Serializable {
  41                 public String fileName;
  42                 public long lastModified;
  43                 public Templates stylesheet;
  44         };
  45
  46         public static final String SERVERNAME = "uwobo-XSLT-server";
  47         public static final String PACKAGE;
  48         public static final String VERSION;
  49         public static final String DATE;
  50         public static final String TIME;
  51         public static final String SERIALIZATION_DIR;
  52
  53         static {
  54                 Properties props = new Properties();
  55                 try {
  56                         InputStream in = Server.class.getResourceAsStream("properties.txt");
  57                         props.load(in);
  58                         in.close();
  59                 } catch (IOException ioe) {
  60                         System.err.println("Could not load the version information.");
  61                 }
  62
  63                 PACKAGE = props.getProperty("PACKAGE");
  64                 VERSION = props.getProperty("VERSION");
  65                 DATE = props.getProperty("DATE");
  66                 TIME = props.getProperty("TIME");
  67                 SERIALIZATION_DIR = props.getProperty("SERIALIZATION_DIR");
  68         }
  69
  70         Server() {
  71            if(!SERIALIZATION_DIR.equals("")) {
  72               log("Looking for serialized stylesheets");
  73               File [] serialized = new File(SERIALIZATION_DIR).listFiles();
  74               if (serialized == null) {
  75                  log("Serialized stylesheets directory \"" + SERIALIZATION_DIR +
  76                   "\" not found");
  77               } else {
  78                  for (int i = 0; i < serialized.length ; i++) {
  79                     File filename = serialized[i];
  80                     String key = filename.getName();
  81                     log("Found serialized stylesheet " + key);
  82                     log("Reloading serialized stylesheet \"" + filename + "\"... ");
  83                     FileInputStream istream;
  84                     try {
  85                        istream = new FileInputStream(filename);
  86                        ObjectInputStream p = new ObjectInputStream(istream);
  87                        Style style = (Style)p.readObject();
  88                        istream.close();
  89                        hashMap.put(key, style);
  90                     } catch (Exception e) {log(e.toString());};
  91                  }
  92                  log("Serialized stylesheets loaded!");
  93               }
  94            } else
  95               log("Stylesheet serialization is off. Set the property SERIALIZATION_DIR to a non-empty value to turn it on.");
  96
  97         }
  98
  99         private final HashMap hashMap = new HashMap();
 100         private static int logCounter = 0;
 101
 102         private final String compileStylesheet(Style style, String key) throws TransformerConfigurationException, SAXException, IOException {
 103                 StreamSource streamsource =
 104                         new StreamSource(new URL(style.fileName).openStream());
 105                 streamsource.setSystemId(style.fileName);
 106                 Templates templates =
 107                    ((SAXTransformerFactory)TransformerFactory.newInstance())
 108                       .newTemplates(streamsource);
 109                 style.stylesheet = templates;
 110                 File serializationFile = new File(SERIALIZATION_DIR,key);
 111                 String res = "";
 112                 if(!SERIALIZATION_DIR.equals("")) {
 113                    try {
 114                       FileOutputStream ostream =
 115                          new FileOutputStream(serializationFile);
 116                       ObjectOutputStream p = new ObjectOutputStream(ostream);
 117                       p.writeObject(style);
 118                       p.flush();
 119                       ostream.close();
 120                       res =
 121                        "Stylesheet serialized in \"" + serializationFile + "\"";
 122                       log(res);
 123                    } catch (FileNotFoundException e) {
 124                       res = "Warning: Stylesheet not " +
 125                          "serialized. Error opening " + "file \"" +
 126                          serializationFile + "\"";
 127                       log(res);
 128                       res = htmlOfWarning(res);
 129                    }
 130                 }
 131                 return res;
 132         }
 133
 134         private String getContentType(Templates templates) {
 135                 final Properties oprops = templates.getOutputProperties();
 136                 final String encoding = oprops.getProperty(OutputKeys.ENCODING);
 137                 final String media = oprops.getProperty(OutputKeys.MEDIA_TYPE);
 138
 139                 if (media != null) {
 140                         if (encoding != null)
 141                                 return media + "; charset=" + encoding;
 142                         return media;
 143                 } else {
 144                         final String method = oprops.getProperty(OutputKeys.METHOD);
 145                         if (method.equals("html"))
 146                                 return "text/html";
 147                         else if (method.equals("text"))
 148                                 return "text/plain";
 149                         else
 150                                 return "text/xml";
 151                 }
 152         }
 153
 154         private final ContentHandler applyStylesheet(Templates stylesheet, HashMap params, ContentHandler saxOutput)
 155         throws TransformerConfigurationException, SAXException
 156         {
 157                 TransformerHandler th = ((SAXTransformerFactory)TransformerFactory.newInstance()).newTransformerHandler(stylesheet);
 158
 159                 th.setResult(new SAXResult(saxOutput));
 160
 161                 if (params != null) {
 162                         final Transformer transformer = th.getTransformer();
 163                         Iterator i = params.keySet().iterator();
 164                         while (i.hasNext()) {
 165                                 final String name = (String) i.next();
 166                                 final String value = (String) params.get(name);
 167                                 transformer.setParameter(name, value);
 168                         }
 169                 }
 170
 171                 return th;
 172         }
 173
 174         private final void parseFile(String datasheet, ContentHandler saxOutput) throws SAXException, IOException, Exception {
 175                 final XMLReader reader = XMLReaderFactory.createXMLReader("org.apache.xerces.parsers.SAXParser");
 176                 reader.setFeature("http://xml.org/sax/features/namespaces", true);
 177                 reader.setFeature("http://xml.org/sax/features/namespace-prefixes", true);
 178                 reader.setContentHandler(saxOutput);
 179                 if (saxOutput instanceof LexicalHandler)
 180                         reader.setProperty("http://xml.org/sax/properties/lexical-handler", (LexicalHandler)saxOutput);
 181                 reader.parse(datasheet);
 182         }
 183
 184         private final ContentHandler saveFile(OutputStream outputStream, Properties props) throws IOException {
 185                 final Serializer ser = SerializerFactory.getSerializer(props);
 186                 ser.setOutputStream(outputStream);
 187                 return ser.asContentHandler();
 188         }
 189
 190         public static void log(String msg) {
 191                 System.err.println(SERVERNAME + "[" + logCounter++ + "]: " + msg);
 192         }
 193
 194         public String add(String filename, String key) throws TransformerConfigurationException, SAXException, IOException {
 195                 log("processing stylesheet \"" + filename + "\" using key " + key + "... ");
 196                 if (hashMap.containsKey(key)) {
 197                    Style style = (Style)hashMap.get(key);
 198                    if (style.fileName.equals(filename)) {
 199                       String msg =
 200                          "Warning: Stylesheet already loaded. Reloading...";
 201                       log(msg);
 202                       String msg2 = reload(key);
 203                       return htmlOfWarning(msg) +
 204                          (msg2.equals("") ? "" : "<br />" + msg2);
 205                    } else {
 206                       String res =
 207                          "Error: There is already a stylesheet with keyword \""+
 208                           key + "\" (aborted)";
 209                       log(res);
 210                       return htmlOfError(res);
 211                    }
 212                 }
 213
 214                 Style style = new Style();
 215                 style.fileName = filename;
 216                 style.lastModified = new File(filename).lastModified();
 217                 String res = compileStylesheet(style,key);
 218                 log("done!");
 219
 220                 hashMap.put(key, style);
 221                 return res;
 222         }
 223
 224         public ArrayList removeAll() throws TransformerConfigurationException, SAXException, IOException {
 225                 ArrayList res = new ArrayList();
 226                 String log = "";
 227                 Iterator i = hashMap.keySet().iterator();
 228                 while (i.hasNext()) {
 229                         String key = (String)i.next();
 230                         Style style = (Style)hashMap.get(key);
 231                         String msg =
 232                          "removing \"" + key + " (" + style.fileName + ")";
 233                         res.add(msg);
 234                         log(msg);
 235                         msg = partialRemove(key,false);
 236                         if(!msg.equals(""))
 237                            res.add(msg);
 238                 }
 239                 hashMap.clear();
 240                 return res;
 241         }
 242
 243         private String partialRemove(String key, boolean removeFromHashTable) {
 244                 String res = "";
 245                 Style style = (Style)hashMap.get(key);
 246                 if (style != null) {
 247                         log("removing \"" + key + " (" + style.fileName + ")");
 248                         if (removeFromHashTable)
 249                            hashMap.remove(key);
 250                         if(!SERIALIZATION_DIR.equals("")) {
 251                            File to_delete = new File(SERIALIZATION_DIR,key);
 252                            if (!to_delete.delete()) {
 253                               res = "Warning: Serialized stylesheet \"" +
 254                                  to_delete + "\" to remove not found";
 255                               log(res);
 256                               res = htmlOfWarning(res);
 257                            }
 258                         }
 259                 } else {
 260                         res = "Error: stylesheet \"" + key + "\" not loaded";
 261                         log(res);
 262                         res = htmlOfError(res);
 263                 }
 264                 return res;
 265         }
 266
 267         public String remove(String key) {
 268            return partialRemove(key,true);
 269         }
 270
 271         public String getContentType(String key) {
 272                 Style style = (Style)hashMap.get(key);
 273                 if (style != null) {
 274                         return getContentType(style.stylesheet);
 275                 } else {
 276                         log("Error, stylesheet \"" + key + "\" not loaded");
 277                         return null;
 278                 }
 279         }
 280
 281         public List list() {
 282                 log("listing stylesheets...");
 283                 ArrayList l = new ArrayList();
 284                 Iterator i = hashMap.keySet().iterator();
 285                 while (i.hasNext()) {
 286                         String key  = (String)i.next();
 287                         Style style = (Style)hashMap.get(key);
 288                         l.add("  " + key + " (" + style.fileName + "; " + getContentType(style.stylesheet) + ")");
 289                         System.out.println("  " + key + " (" + style.fileName + ")");
 290                 }
 291                 log("done!");
 292                 return l;
 293         }
 294
 295         private ContentHandler applyRec(final Key[] keys, int idx, final ContentHandler saxOutput)
 296         throws TransformerConfigurationException, SAXException, IOException
 297         {
 298                 if (idx < 0)
 299                         return saxOutput;
 300                 else {
 301                         final Style style = (Style) hashMap.get(keys[idx].name);
 302                         if (style == null) {
 303                                 log("cannot apply unknwon stylesheet \"" + keys[idx].name + "\" (aborted)");
 304                                 return null;
 305                         }
 306                         return applyStylesheet(style.stylesheet, keys[idx].params, applyRec(keys, idx - 1, saxOutput));
 307                 }
 308         }
 309
 310         public void apply(String inFile, OutputStream outputStream, Key[] keys, Properties userProperties)
 311         throws IOException, TransformerConfigurationException, SAXException, Exception
 312         {
 313 /*              File outFile = new File(outFilename);
 314                 if (outFile.exists())
 315                         System.out.println("Using cached version\n");
 316                 else {
 317 */
 318                         final Key[] rkeys = new Key[keys.length];
 319                         for (int i = 0; i < keys.length; i++)
 320                                 rkeys[i] = keys[keys.length - i - 1];
 321
 322                         Properties outputProperties;
 323                         Properties defaultProperties;
 324                         String method;
 325
 326                         if (keys.length > 0) {
 327                                 Style style = (Style) hashMap.get(rkeys[0].name);
 328                                 if (style == null) {
 329                                         log("Error, stylesheet \"" + rkeys[0].name + "\" not loaded");
 330                                         return;
 331                                 }
 332                                 outputProperties = style.stylesheet.getOutputProperties();
 333                                 method = userProperties.getProperty("method");
 334                                 if (method == null) method = outputProperties.getProperty("method");
 335                                 if (method == null) method = "xml";
 336                                 defaultProperties = org.apache.xalan.templates.OutputProperties.getDefaultMethodProperties(method);
 337                         } else {
 338                                 method = userProperties.getProperty("method");
 339                                 if (method == null) method = "xml";
 340                                 outputProperties = org.apache.xalan.templates.OutputProperties.getDefaultMethodProperties(method);
 341                                 defaultProperties = outputProperties;
 342                         }
 343
 344                         for (Enumeration e = userProperties.propertyNames(); e.hasMoreElements(); ) {
 345                                 String prop = (String) e.nextElement();
 346                                 String value = userProperties.getProperty(prop);
 347                                 if (value.equals("")) {
 348                                         String defaultValue = defaultProperties.getProperty(prop);
 349                                         if (defaultValue != null)
 350                                                 outputProperties.setProperty(prop, defaultProperties.getProperty(prop));
 351                                         else
 352                                                 outputProperties.remove(prop);
 353                                 } else {
 354                                         outputProperties.setProperty(prop, value);
 355                                 }
 356                         }
 357
 358                         parseFile(inFile, applyRec(rkeys, rkeys.length - 1, saveFile(outputStream, outputProperties)));
 359 //              }
 360         }
 361
 362         public ArrayList reloadAll() throws TransformerConfigurationException, SAXException, IOException {
 363                 ArrayList res = new ArrayList();
 364                 Iterator i = hashMap.keySet().iterator();
 365                 while (i.hasNext()) {
 366                         String key = (String)i.next();
 367                         Style style = (Style)hashMap.get(key);
 368                         String msg =
 369                          "reloading \"" + key + " (" + style.fileName + ")";
 370                         res.add(msg);
 371                         log(msg);
 372                         msg = reload(key);
 373                         if(!msg.equals(""))
 374                            res.add(msg);
 375                 }
 376                 return res;
 377         }
 378
 379         public String reload(String key) throws TransformerConfigurationException, SAXException, IOException {
 380                 String res = "";
 381                 Style style = (Style)hashMap.get(key);
 382                 if (style != null) {
 383                    log("reloading \"" + key + "\"... ");
 384                    style.lastModified = new File(style.fileName).lastModified();
 385                    res= compileStylesheet(style,key);
 386                    log("done!");
 387                 } else {
 388                         res = "Error: stylesheet \"" + key + "\" not loaded";
 389                         log(res);
 390                         res = htmlOfError(res);
 391                 }
 392                 return res;
 393         }
 394
 395         private String htmlOfWarning(String message)
 396         {
 397            return "<b style=\"color: maroon\">" + message+"</b>";
 398         }
 399
 400         private String htmlOfError(String message)
 401         {
 402            return "<b style=\"color: red\">" + message+"</b>";
 403         }
 404 }