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16 package org.outerj.daisy.frontend.components.skinsource;
17
18 import org.apache.excalibur.source.*;
19 import org.apache.avalon.framework.context.Contextualizable;
20 import org.apache.avalon.framework.context.Context;
21 import org.apache.avalon.framework.context.ContextException;
22 import org.apache.avalon.framework.service.ServiceManager;
23 import org.apache.avalon.framework.service.ServiceException;
24 import org.apache.avalon.framework.service.Serviceable;
25 import org.apache.avalon.framework.activity.Disposable;
26 import org.apache.avalon.framework.activity.Initializable;
27 import org.apache.avalon.framework.logger.AbstractLogEnabled;
28 import org.apache.avalon.framework.thread.ThreadSafe;
29 import org.apache.avalon.excalibur.monitor.ActiveMonitor;
30 import org.apache.avalon.excalibur.monitor.Resource;
31 import org.apache.cocoon.components.ContextHelper;
32 import org.apache.cocoon.environment.Request;
33 import org.outerj.daisy.frontend.util.AltFileResource;
34 import org.outerj.daisy.frontend.util.WikiDataDirHelper;
35 import org.outerj.daisy.frontend.WikiHelper;
36
37 import java.util.Map  ;
38 import java.util.HashSet ;
39 import java.io.*;
40 import java.net.MalformedURLException ;
41 import java.net.URL ;
42 import java.beans.PropertyChangeListener ;
43 import java.beans.PropertyChangeEvent ;
44
45 import EDU.oswego.cs.dl.util.concurrent.ConcurrentReaderHashMap;
46 import EDU.oswego.cs.dl.util.concurrent.Mutex;
47
48
54 public class SkinSourceFactory extends AbstractLogEnabled implements SourceFactory, Contextualizable, Serviceable,
55 Disposable, ThreadSafe, Initializable {
56 private Context context;
57
60 private Map baseSkinCache = new ConcurrentReaderHashMap();
61
64 private Mutex updateMutex = new Mutex();
65 private ActiveMonitor monitor;
66 private ServiceManager serviceManager;
67 private static final String BASE_SKIN_FILENAME = "baseskin.txt";
68 private File skinsDir;
69 private File skinsFallbackDir;
70
71 public void contextualize(Context context) throws ContextException {
72 this.context = context;
73 }
74
75 public void service(ServiceManager serviceManager) throws ServiceException {
76 this.serviceManager = serviceManager;
77 monitor = (ActiveMonitor)serviceManager.lookup(ActiveMonitor.ROLE);
78 }
79
80 public void initialize() throws Exception {
81 this.skinsDir = new File(new File(WikiDataDirHelper.getWikiDataDir(context)), "resources" + File.separator + "skins").getAbsoluteFile();
82 }
83
84 public void dispose() {
85 serviceManager.release(monitor);
86 }
87
88 public Source getSource(String location, Map parameters) throws IOException, MalformedURLException {
89 Request request = ContextHelper.getRequest(context);
90 initFallbackDir();
91
92 String [] parsedLocation = parseLocation(location);
93
94 String skin;
95 if (parsedLocation[0] != null) {
96 skin = parsedLocation[0];
97 } else {
98 skin = (String )request.getAttribute("skin");
99 if (skin == null)
100 throw new IOException("Missing \"skin\" attribute in the Cocoon Request object.");
101 }
102
103 boolean forceFallback = parsedLocation[1] != null;
104
105 String path = parsedLocation[2];
106
107 File skinFallbackDir = new File(skinsFallbackDir, skin);
108 File skinFallbackResource = new File(skinFallbackDir, path);
109 File skinDir = new File(skinsDir, skin);
110 File skinResource = forceFallback ? skinFallbackResource : new File(skinDir, path);
111 File skinOriginalResource = skinResource;
112 File skinSelectedSource;
113
114 HashSet searchedParentSkins = null;
115
116 while ((skinSelectedSource = getExistingFile(skinResource, skinFallbackResource)) == null) {
117 String parentSkin = getBaseSkin(skinDir);
118 parentSkin = parentSkin == null ? getBaseSkin(skinFallbackDir) : parentSkin;
119 if (parentSkin != null) {
120 if (searchedParentSkins != null && searchedParentSkins.contains(parentSkin))
121 throw new IOException("Recursive skin dependency found for skin \"" + skin + "\" and base skin \"" + parentSkin + "\".");
122
123 skinFallbackDir = new File(skinsFallbackDir, parentSkin);
124 skinFallbackResource = new File(skinFallbackDir, path);
125 skinDir = new File(skinsDir, parentSkin);
126 skinResource = forceFallback ? skinFallbackResource : new File(skinDir, path);
127
128 if (searchedParentSkins == null)
129 searchedParentSkins = new HashSet ();
130 searchedParentSkins.add(parentSkin);
131 } else {
132 skinSelectedSource = skinOriginalResource;
134 break;
135 }
136 }
137
138 StringBuffer absoluteURL = new StringBuffer (150);
140 absoluteURL.append("daisyskin:/(").append(skin).append(')');
141 if (forceFallback)
142 absoluteURL.append("(webapp)");
143 absoluteURL.append(path);
144
145 return new SkinSource(skinSelectedSource, absoluteURL.toString());
146 }
147
148 private File getExistingFile(File firstChoice, File secondChoice) {
149 if (firstChoice.exists())
150 return firstChoice;
151 else if (secondChoice.exists())
152 return secondChoice;
153 else
154 return null;
155 }
156
157 private String [] parseLocation(String location) throws MalformedURLException {
158 if (!location.startsWith("daisyskin:"))
159 throw new MalformedURLException ("The URL does not use the daisyskin sheme, it cannot be handled by this source implementation.");
160
161 String schemeSpecificPart = location.substring("daisyskin:".length());
162
163 String skinName;
164 String locationName; String path;
166
167 if (schemeSpecificPart.startsWith("/(")) {
168 int closeSkinNameParenPos = schemeSpecificPart.indexOf(')');
169 if (closeSkinNameParenPos == -1)
170 throw new MalformedURLException ("Missing closing parenthesis in: " + location);
171 skinName = schemeSpecificPart.substring(2, closeSkinNameParenPos);
172 if (skinName.trim().equals("")) {
173 skinName = null;
176 }
177 int pathStartPos = closeSkinNameParenPos + 1;
178 if (schemeSpecificPart.length() > closeSkinNameParenPos && schemeSpecificPart.charAt(closeSkinNameParenPos + 1) == '(') {
179 int locationNameParenPos = schemeSpecificPart.indexOf(')', closeSkinNameParenPos + 1);
180 if (locationNameParenPos == -1)
181 throw new MalformedURLException ("Missing closing parenthesis in: " + location);
182 locationName = schemeSpecificPart.substring(closeSkinNameParenPos + 2, locationNameParenPos);
183 if (locationName.trim().equals("")) {
184 locationName = null;
185 } else if (!locationName.equals("webapp")) {
186 throw new MalformedURLException ("The location name in the URL, when specified, should be 'webapp'.");
187 }
188 pathStartPos = locationNameParenPos + 1;
189 } else {
190 locationName = null;
191 }
192 path = schemeSpecificPart.substring(pathStartPos);
193 } else {
194 skinName = null;
195 locationName = null;
196 path = schemeSpecificPart;
197 }
198
199 return new String [] {skinName, locationName, path};
200 }
201
202 private String getBaseSkin(File skinDir) throws IOException {
203 CachedEntry cachedEntry = (CachedEntry)baseSkinCache.get(skinDir);
204 if (cachedEntry != null)
205 return cachedEntry.baseSkin;
206
207 if (!skinDir.exists())
208 return null;
209
210 try {
211 updateMutex.acquire();
212 } catch (InterruptedException e) {
213 throw new IOException("Error doing updateMutex.acquire(): " + e.toString());
214 }
215 try {
216 cachedEntry = (CachedEntry)baseSkinCache.get(skinDir);
217 if (cachedEntry != null)
218 return cachedEntry.baseSkin;
219
220 File baseSkinFile = new File(skinDir, BASE_SKIN_FILENAME);
221 String baseSkin = loadBaseSkin(baseSkinFile);
222
223 Resource fileResource;
224 try {
225 fileResource = new AltFileResource(baseSkinFile);
226 } catch (Exception e) {
227 throw new IOException("Error constructing FileResource object for " + baseSkinFile.getAbsolutePath() + ": " + e.toString());
228 }
229 fileResource.addPropertyChangeListener(new BaseSkinListener(skinDir));
230 cachedEntry = new CachedEntry(baseSkin, fileResource);
231 baseSkinCache.put(skinDir, cachedEntry);
232 monitor.addResource(fileResource);
233
234 return baseSkin;
235 } finally {
236 updateMutex.release();
237 }
238 }
239
240 static class CachedEntry {
241 public String baseSkin;
242 public Resource fileResource;
243
244 public CachedEntry(String baseSkin, Resource fileResource) {
245 this.baseSkin = baseSkin;
246 this.fileResource = fileResource;
247 }
248 }
249
250 class BaseSkinListener implements PropertyChangeListener {
251 private File skinDir;
252
253 public BaseSkinListener(File skinDir) {
254 this.skinDir = skinDir;
255 }
256
257 public void propertyChange(PropertyChangeEvent evt) {
258 if (getLogger().isDebugEnabled()) {
259 getLogger().debug("Received change event for " + ((Resource)evt.getSource()).getResourceKey());
260 }
261
262 try {
263 updateMutex.acquire();
264 try {
265 Resource fileResource = (Resource)evt.getSource();
266
267 if (!skinDir.exists()) {
268 baseSkinCache.remove(skinDir);
269 monitor.removeResource(fileResource);
270 } else {
271 CachedEntry cachedEntry = (CachedEntry)baseSkinCache.get(skinDir);
272 if (cachedEntry != null) {
273 File baseSkinFile = new File(skinDir, BASE_SKIN_FILENAME);
274 cachedEntry.baseSkin = loadBaseSkin(baseSkinFile);
275 } else {
276 monitor.removeResource(fileResource);
278 }
279 }
280 } finally {
281 updateMutex.release();
282 }
283 } catch (Exception e) {
284 getLogger().error("Error processing baseskin.txt change event for " + skinDir.getAbsolutePath(), e);
285 }
286 }
287 }
288
289 private String loadBaseSkin(File baseSkinFile) throws IOException {
290 if (baseSkinFile.exists()) {
291 String baseskin = null;
292 FileReader fileReader = null;
293 try {
294 fileReader = new FileReader(baseSkinFile);
295 BufferedReader reader = new BufferedReader(fileReader);
296 baseskin = reader.readLine();
297 } catch (Exception e) {
298 throw new IOException("Error reading baseskin.txt file at " + baseSkinFile.getAbsolutePath());
299 } finally {
300 if (fileReader != null)
301 fileReader.close();
302 }
303
304 if (baseskin == null) {
305 return null;
306 } else {
307 baseskin = baseskin.trim();
308 if (baseskin.length() == 0)
309 return null;
310 else
311 return baseskin;
312 }
313 }
314 return null;
315 }
316
317 public void release(Source source) {
318 }
319
320 private void initFallbackDir() throws MalformedURLException {
321 if (skinsFallbackDir == null) {
322 synchronized(this) {
323 if (skinsFallbackDir == null) {
324 Request request = ContextHelper.getRequest(context);
325 File contextDir = new File(new URL (WikiHelper.getDaisyContextPath(request)).getPath());
326 skinsFallbackDir = new File(contextDir, "resources" + File.separator + "skins").getAbsoluteFile();
327 }
328 }
329 }
330 }
331 }
332 |
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