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 {
  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
  52         static {
  53                 Properties props = new Properties();
  54                 try {
  55                         InputStream in = Server.class.getResourceAsStream("properties.txt");
  56                         props.load(in);
  57                         in.close();
  58                 } catch (IOException ioe) {
  59                         System.err.println("Could not load the version information.");
  60                 }
  61
  62                 PACKAGE = props.getProperty("PACKAGE");
  63                 VERSION = props.getProperty("VERSION");
  64                 DATE = props.getProperty("DATE");
  65                 TIME = props.getProperty("TIME");
  66         }
  67
  68         private final HashMap hashMap = new HashMap();
  69         private static int logCounter = 0;
  70
  71         private final Templates compileStylesheet(String xsl_file) throws TransformerConfigurationException, SAXException, IOException {
  72                 StreamSource streamsource =
  73                         new StreamSource(new URL(xsl_file).openStream());
  74                 streamsource.setSystemId(xsl_file);
  75                 return ((SAXTransformerFactory)TransformerFactory.newInstance())
  76                         .newTemplates(streamsource);
  77         }
  78
  79         private String getContentType(Templates templates) {
  80                 final Properties oprops = templates.getOutputProperties();
  81                 final String encoding = oprops.getProperty(OutputKeys.ENCODING);
  82                 final String media = oprops.getProperty(OutputKeys.MEDIA_TYPE);
  83
  84                 if (media != null) {
  85                         if (encoding != null)
  86                                 return media + "; charset=" + encoding;
  87                         return media;
  88                 } else {
  89                         final String method = oprops.getProperty(OutputKeys.METHOD);
  90                         if (method.equals("html"))
  91                                 return "text/html";
  92                         else if (method.equals("text"))
  93                                 return "text/plain";
  94                         else
  95                                 return "text/xml";
  96                 }
  97         }
  98
  99         private final ContentHandler applyStylesheet(Templates stylesheet, HashMap params, ContentHandler saxOutput)
 100         throws TransformerConfigurationException, SAXException
 101         {
 102                 TransformerHandler th = ((SAXTransformerFactory)TransformerFactory.newInstance()).newTransformerHandler(stylesheet);
 103
 104                 th.setResult(new SAXResult(saxOutput));
 105
 106                 if (params != null) {
 107                         final Transformer transformer = th.getTransformer();
 108                         Iterator i = params.keySet().iterator();
 109                         while (i.hasNext()) {
 110                                 final String name = (String) i.next();
 111                                 final String value = (String) params.get(name);
 112                                 transformer.setParameter(name, value);
 113                         }
 114                 }
 115
 116                 return th;
 117         }
 118
 119         private final void parseFile(String datasheet, ContentHandler saxOutput) throws SAXException, IOException, Exception {
 120                 final XMLReader reader = XMLReaderFactory.createXMLReader("org.apache.xerces.parsers.SAXParser");
 121                 reader.setFeature("http://xml.org/sax/features/namespaces", true);
 122                 reader.setFeature("http://xml.org/sax/features/namespace-prefixes", true);
 123                 reader.setContentHandler(saxOutput);
 124                 if (saxOutput instanceof LexicalHandler)
 125                         reader.setProperty("http://xml.org/sax/properties/lexical-handler", (LexicalHandler)saxOutput);
 126                 reader.parse(datasheet);
 127         }
 128
 129         private final ContentHandler saveFile(OutputStream outputStream, Properties props) throws IOException {
 130                 final Serializer ser = SerializerFactory.getSerializer(props);
 131                 ser.setOutputStream(outputStream);
 132                 return ser.asContentHandler();
 133         }
 134
 135         public static void log(String msg) {
 136                 System.err.println(SERVERNAME + "[" + logCounter++ + "]: " + msg);
 137         }
 138
 139         public void add(String filename, String key) throws TransformerConfigurationException, SAXException, IOException {
 140                 if (hashMap.containsKey(key)) {
 141                         log("there is already a stylesheet with keyword \"" + key + "\" (aborted)");
 142                         return;
 143                 }
 144
 145                 Style style = new Style();
 146                 style.fileName = filename;
 147                 style.lastModified = new File(filename).lastModified();
 148                 log("processing stylesheet \"" + filename + "\"... ");
 149                 style.stylesheet = compileStylesheet(filename);
 150                 log("done!");
 151
 152                 hashMap.put(key, style);
 153         }
 154
 155         public void removeAll() throws TransformerConfigurationException, SAXException, IOException {
 156                 String key;
 157                 Style style;
 158                 Iterator i = hashMap.keySet().iterator();
 159                 while (i.hasNext()) {
 160                         key = (String)i.next();
 161                         style = (Style)hashMap.get(key);
 162                         log("removing \"" + key + " (" + style.fileName + ")");
 163                 }
 164                 hashMap.clear();
 165         }
 166
 167         public void remove(String key) {
 168                 Style style = (Style)hashMap.get(key);
 169                 if (style != null) {
 170                         log("removing \"" + key + " (" + style.fileName + ")");
 171                         hashMap.remove(key);
 172                 } else {
 173                         log("error, stylesheet \"" + key + "\" not loaded");
 174                 }
 175         }
 176
 177         public String getContentType(String key) {
 178                 Style style = (Style)hashMap.get(key);
 179                 if (style != null) {
 180                         return getContentType(style.stylesheet);
 181                 } else {
 182                         log("error, stylesheet \"" + key + "\" not loaded");
 183                         return null;
 184                 }
 185         }
 186
 187         public List list() {
 188                 log("listing stylesheets...");
 189                 ArrayList l = new ArrayList();
 190                 Iterator i = hashMap.keySet().iterator();
 191                 while (i.hasNext()) {
 192                         String key  = (String)i.next();
 193                         Style style = (Style)hashMap.get(key);
 194                         l.add("  " + key + " (" + style.fileName + "; " + getContentType(style.stylesheet) + ")");
 195                         System.out.println("  " + key + " (" + style.fileName + ")");
 196                 }
 197                 log("done!");
 198                 return l;
 199         }
 200
 201         private ContentHandler applyRec(final Key[] keys, int idx, final ContentHandler saxOutput)
 202         throws TransformerConfigurationException, SAXException, IOException
 203         {
 204                 if (idx < 0)
 205                         return saxOutput;
 206                 else {
 207                         final Style style = (Style) hashMap.get(keys[idx].name);
 208                         if (style == null) {
 209                                 log("cannot apply unknwon stylesheet \"" + keys[idx].name + "\" (aborted)");
 210                                 return null;
 211                         }
 212                         return applyStylesheet(style.stylesheet, keys[idx].params, applyRec(keys, idx - 1, saxOutput));
 213                 }
 214         }
 215
 216         public void apply(String inFile, OutputStream outputStream, Key[] keys, Properties userProperties)
 217         throws FileNotFoundException, IOException, TransformerConfigurationException, SAXException, Exception
 218         {
 219 /*              File outFile = new File(outFilename);
 220                 if (outFile.exists())
 221                         System.out.println("Using cached version\n");
 222                 else {
 223 */
 224                         final Key[] rkeys = new Key[keys.length];
 225                         for (int i = 0; i < keys.length; i++)
 226                                 rkeys[i] = keys[keys.length - i - 1];
 227
 228                         Properties outputProperties;
 229                         Properties defaultProperties;
 230                         String method;
 231
 232                         if (keys.length > 0) {
 233                                 Style style = (Style) hashMap.get(rkeys[0].name);
 234                                 if (style == null) {
 235                                         log("error, stylesheet \"" + rkeys[0].name + "\" not loaded");
 236                                         return;
 237                                 }
 238                                 outputProperties = style.stylesheet.getOutputProperties();
 239                                 method = userProperties.getProperty("method");
 240                                 if (method == null) method = outputProperties.getProperty("method");
 241                                 if (method == null) method = "xml";
 242                                 defaultProperties = org.apache.xalan.templates.OutputProperties.getDefaultMethodProperties(method);
 243                         } else {
 244                                 method = userProperties.getProperty("method");
 245                                 if (method == null) method = "xml";
 246                                 outputProperties = org.apache.xalan.templates.OutputProperties.getDefaultMethodProperties(method);
 247                                 defaultProperties = outputProperties;
 248                         }
 249
 250                         for (Enumeration e = userProperties.propertyNames(); e.hasMoreElements(); ) {
 251                                 String prop = (String) e.nextElement();
 252                                 String value = userProperties.getProperty(prop);
 253                                 if (value.equals("")) {
 254                                         String defaultValue = defaultProperties.getProperty(prop);
 255                                         if (defaultValue != null)
 256                                                 outputProperties.setProperty(prop, defaultProperties.getProperty(prop));
 257                                         else
 258                                                 outputProperties.remove(prop);
 259                                 } else {
 260                                         outputProperties.setProperty(prop, value);
 261                                 }
 262                         }
 263
 264                         parseFile(inFile, applyRec(rkeys, rkeys.length - 1, saveFile(outputStream, outputProperties)));
 265 //              }
 266         }
 267
 268         public void reloadAll() throws TransformerConfigurationException, SAXException, IOException {
 269                 Iterator i = hashMap.keySet().iterator();
 270                 while (i.hasNext())
 271                         reload((String)i.next());
 272         }
 273
 274         public void reload(String key) throws TransformerConfigurationException, SAXException, IOException {
 275                 Style style = (Style)hashMap.get(key);
 276
 277                 log("reloading \"" + key + "\"... ");
 278                 style.stylesheet = compileStylesheet(style.fileName);
 279                 style.lastModified = new File(style.fileName).lastModified();
 280                 log("done!");
 281         }
 282
 283         public void updateAll() throws TransformerConfigurationException, SAXException, IOException {
 284                 Iterator i = hashMap.keySet().iterator();
 285                 while (i.hasNext())
 286                         update((String)i.next());
 287         }
 288
 289         public void update(String key) throws TransformerConfigurationException, SAXException, IOException {
 290                 Style style = (Style)hashMap.get(key);
 291
 292                 log("updating \"" + key + "\"... ");
 293                 File styleFile = new File(style.fileName);
 294                 if (styleFile.lastModified() > style.lastModified) {
 295                         style.stylesheet = compileStylesheet(style.fileName);
 296                         style.lastModified = styleFile.lastModified();
 297                         log("done!");
 298                 } else
 299                         log("\"" + key + "\" is up to date");
 300         }
 301 }