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1
19 package org.apache.cayenne.cache;
20
21 import java.util.Collection  ;
22 import java.util.Collections ;
23 import java.util.HashMap ;
24 import java.util.Iterator ;
25 import java.util.List ;
26 import java.util.Map ;
27 import java.util.Properties ;
28
29 import org.apache.cayenne.CayenneRuntimeException;
30 import org.apache.cayenne.query.QueryMetadata;
31
32 import com.opensymphony.oscache.base.CacheEntry;
33 import com.opensymphony.oscache.base.NeedsRefreshException;
34 import com.opensymphony.oscache.general.GeneralCacheAdministrator;
35
36
78 public class OSQueryCache implements QueryCache {
79
80 public static final int DEFAULT_REFRESH_PERIOD = CacheEntry.INDEFINITE_EXPIRY;
81
82 static String DEFAULT_REFRESH_KEY = "cayenne.default.refresh";
83 static String DEFAULT_CRON_KEY = "cayenne.default.cron";
84
85 static String GROUP_PREFIX = "cayenne.group.";
86 static String REFRESH_SUFFIX = ".refresh";
87 static String CRON_SUFFIX = ".cron";
88
89 protected GeneralCacheAdministrator osCache;
90
91 RefreshSpecification defaultRefreshSpecification;
92 Map refreshSpecifications;
93 Properties properties;
94
95 public OSQueryCache() {
96 OSCacheAdministrator admin = new OSCacheAdministrator();
97 init(admin, admin.getProperties());
98 }
99
100 public OSQueryCache(GeneralCacheAdministrator cache, Properties properties) {
101 init(cache, properties);
102 }
103
104
108 public Collection getGroupNames() {
109 return refreshSpecifications != null
110 ? Collections.unmodifiableCollection(refreshSpecifications.keySet())
111 : Collections.EMPTY_SET;
112 }
113
114 public String getCronExpression(String groupName) {
115
116 RefreshSpecification spec = null;
117
118 if (refreshSpecifications != null) {
119 spec = (RefreshSpecification) refreshSpecifications.get(groupName);
120 }
121
122 if (spec == null) {
123 spec = defaultRefreshSpecification;
124 }
125
126 return spec.cronExpression;
127 }
128
129 public int getRrefreshPeriod(String groupName) {
130
131 RefreshSpecification spec = null;
132
133 if (refreshSpecifications != null) {
134 spec = (RefreshSpecification) refreshSpecifications.get(groupName);
135 }
136
137 if (spec == null) {
138 spec = defaultRefreshSpecification;
139 }
140
141 return spec.refreshPeriod;
142 }
143
144
147 public GeneralCacheAdministrator getOsCache() {
148 return osCache;
149 }
150
151
155 public Properties getProperties() {
156 return properties;
157 }
158
159 void init(GeneralCacheAdministrator cache, Properties properties) {
160 this.properties = properties;
161 this.osCache = cache;
162 this.defaultRefreshSpecification = new RefreshSpecification();
163
164 if (properties != null) {
166
167 String defaultRefresh = properties.getProperty(DEFAULT_REFRESH_KEY);
169 if (defaultRefresh != null) {
170 defaultRefreshSpecification.setRefreshPeriod(defaultRefresh);
171 }
172
173 String defaultCron = properties.getProperty(DEFAULT_CRON_KEY);
174 if (defaultCron != null) {
175 defaultRefreshSpecification.cronExpression = defaultCron;
176 }
177
178 Iterator it = properties.entrySet().iterator();
180 while (it.hasNext()) {
181
182 Map.Entry entry = (Map.Entry ) it.next();
183
184 if (entry.getKey() == null || entry.getValue() == null) {
185 continue;
186 }
187
188 String key = entry.getKey().toString();
189 if (key.startsWith(GROUP_PREFIX)) {
190
191 if (key.endsWith(REFRESH_SUFFIX)) {
192 String name = key.substring(GROUP_PREFIX.length(), key.length()
193 - REFRESH_SUFFIX.length());
194
195 initRefreshPolicy(name, entry.getValue());
196 }
197 else if (key.endsWith(CRON_SUFFIX)) {
198 String name = key.substring(GROUP_PREFIX.length(), key.length()
199 - CRON_SUFFIX.length());
200
201 initCronPolicy(name, entry.getValue());
202 }
203 }
204 }
205 }
206 }
207
208
213 protected void initCronPolicy(String groupName, Object value) {
214 nonNullSpec(groupName).cronExpression = value != null ? value.toString() : null;
215 }
216
217
222 protected void initRefreshPolicy(String groupName, Object value) {
223 nonNullSpec(groupName).setRefreshPeriod(value);
224 }
225
226 private RefreshSpecification nonNullSpec(String name) {
227 if (refreshSpecifications == null) {
228 refreshSpecifications = new HashMap ();
229 }
230
231 RefreshSpecification spec = (RefreshSpecification) refreshSpecifications
232 .get(name);
233 if (spec == null) {
234 spec = new RefreshSpecification();
235 spec.cronExpression = defaultRefreshSpecification.cronExpression;
236 spec.refreshPeriod = defaultRefreshSpecification.refreshPeriod;
237 refreshSpecifications.put(name, spec);
238 }
239
240 return spec;
241 }
242
243 public List get(QueryMetadata metadata) {
244 String key = metadata.getCacheKey();
245 if (key == null) {
246 return null;
247 }
248
249 RefreshSpecification refresh = getRefreshSpecification(metadata);
250
251 try {
252 return (List ) osCache.getFromCache(
253 key,
254 refresh.refreshPeriod,
255 refresh.cronExpression);
256 }
257 catch (NeedsRefreshException e) {
258 osCache.cancelUpdate(key);
259 return null;
260 }
261 }
262
263
269 public List get(QueryMetadata metadata, QueryCacheEntryFactory factory) {
270 String key = metadata.getCacheKey();
271 if (key == null) {
272 return null;
273 }
274
275 RefreshSpecification refresh = getRefreshSpecification(metadata);
276
277 try {
278 return (List ) osCache.getFromCache(
279 key,
280 refresh.refreshPeriod,
281 refresh.cronExpression);
282 }
283 catch (NeedsRefreshException e) {
284 boolean updated = false;
285 try {
286 Object result = factory.createObject();
287
288 if (!(result instanceof List )) {
289 if (result == null) {
290 throw new CayenneRuntimeException("Null on cache rebuilding: "
291 + metadata.getCacheKey());
292 }
293 else {
294 throw new CayenneRuntimeException(
295 "Invalid query result, expected List, got "
296 + result.getClass().getName());
297 }
298 }
299
300 List list = (List ) result;
301
302 put(metadata, list);
303 updated = true;
304 return list;
305 }
306 finally {
307 if (!updated) {
308 osCache.cancelUpdate(key);
311 }
312 }
313 }
314 }
315
316
319 RefreshSpecification getRefreshSpecification(QueryMetadata metadata) {
320
321 RefreshSpecification refresh = null;
322
323 if (refreshSpecifications != null) {
324 String [] groups = metadata.getCacheGroups();
325 if (groups != null && groups.length > 0) {
326 refresh = (RefreshSpecification) refreshSpecifications.get(groups[0]);
327 }
328 }
329
330 return refresh != null ? refresh : defaultRefreshSpecification;
331 }
332
333 public void put(QueryMetadata metadata, List results) {
334 String key = metadata.getCacheKey();
335 if (key != null) {
336 osCache.putInCache(key, results, metadata.getCacheGroups());
337 }
338 }
339
340 public void remove(String key) {
341 if (key != null) {
342 osCache.removeEntry(key);
343 }
344 }
345
346 public void removeGroup(String groupKey) {
347 if (groupKey != null) {
348 osCache.flushGroup(groupKey);
349 }
350 }
351
352 public void clear() {
353 osCache.flushAll();
354 }
355
356 public int size() {
357 return osCache.getCache().getSize();
358 }
359
360 public int capacity() {
361 return osCache.getCache().getCapacity();
362 }
363
364 final static class RefreshSpecification {
365
366 int refreshPeriod;
367 String cronExpression;
368
369 RefreshSpecification() {
370 this.refreshPeriod = DEFAULT_REFRESH_PERIOD;
371 }
372
373 RefreshSpecification(int refrehsPeriod, String cronExpression) {
374 this.refreshPeriod = refrehsPeriod;
375 this.cronExpression = cronExpression;
376 }
377
378 void setRefreshPeriod(Object value) {
379 try {
380 refreshPeriod = Integer.parseInt(value.toString());
381 }
382 catch (NumberFormatException e) {
383 }
385 }
386 }
387
388 final class OSCacheAdministrator extends GeneralCacheAdministrator {
389
390 OSCacheAdministrator() {
391 }
392
393 OSCacheAdministrator(Properties properties) {
394 super(properties);
395 }
396
397 Properties getProperties() {
398 return super.config.getProperties();
399 }
400 }
401 }
402 |
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