DistributedCachePeer


1   /*
2     Copyright (C) 2003  Know Gate S.L. All rights reserved.
3                         C/O�a, 107 1�2 28050 Madrid (Spain)
4   
5     Redistribution and use in source and binary forms, with or without
6     modification, are permitted provided that the following conditions
7     are met:
8   
9     1. Redistributions of source code must retain the above copyright
10       notice, this list of conditions and the following disclaimer.
11  
12    2. The end-user documentation included with the redistribution,
13       if any, must include the following acknowledgment:
14       "This product includes software parts from hipergate
15       (http://www.hipergate.org/)."
16       Alternately, this acknowledgment may appear in the software itself,
17       if and wherever such third-party acknowledgments normally appear.
18  
19    3. The name hipergate must not be used to endorse or promote products
20       derived from this software without prior written permission.
21       Products derived from this software may not be called hipergate,
22       nor may hipergate appear in their name, without prior written
23       permission.
24  
25    This library is distributed in the hope that it will be useful,
26    but WITHOUT ANY WARRANTY; without even the implied warranty of
27    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
28  
29    You should have received a copy of hipergate License with this code;
30    if not, visit http://www.hipergate.org or mail to info@hipergate.org
31  */
32  
33  package com.knowgate.cache;
34  
35  import java.rmi.RemoteException  ;
36  
37  import java.io.ByteArrayOutputStream  ;
38  import java.io.IOException  ;
39  
40  import java.util.Date  ;
41  import java.util.Properties  ;
42  import java.util.Iterator  ;
43  
44  
45  import java.net.URL  ;
46  import java.net.MalformedURLException  ;
47  
48  import com.knowgate.debug.DebugFile;
49  import com.knowgate.misc.Environment;
50  import com.knowgate.dataobjs.DBSubset;
51  
52  /**
53   * <p>Distributed Cache Local Peer</p>
54   * <p>Each distributed cache peer holds its own local copy of cached data.</p>
55   * <p>On the simplest scenenario there is only one client cache peer witch
56   * stores data localy for faster access and reduce network bandwitch consumption.</p>
57   * <p>As data is kept localy at each peer, when more than one client peer concurrently
58   * access the same data, a cache coordinator becomes necessary.</p>
59   * <p>The cache coordinator is an EJB that must be installed at an application server
60   * such as JBoss or BEA Weblogic. See cache.DistributedCacheCoordinatorBean for more
61   * information about the cache coordinator.</p>
62   * <br>
63   * <p><b>Distributed Cache Tokens and Policies</b></p>
64   * <p>A cache peer is essentially a named set of objects. Each object name is called
65   * a "cache token". Cache Token associate a String (the object name) with the actual cached object.</p>
66   * <p>Token have an usage count and a last usage date, each time a token is requested its usage count
67   * and last usage dates are updated at the cache peer.</p>
68   * <p>The cache peer the applies a customizable Policy for discarding objects as cache becomes full.</p>
69   * <p>Currently only a Least Recently Used Cache Policy is provided.</p>
70   * <p>By default the cache has a maximum of 400 objects slots.</p>
71   * <p>There is no checking of memory consumption for the cache peer, it is the programmer's responsability
72   * not to cache objects that are too large.</p>
73   * <p>It is also the programmer's task to remove tokens from the cache peer when the cached data has been changed.</p>
74   * <p><b>Comunnication between client cache peers and the cache coordinator</b></p>
75   * <p>The cache coordinator is a single object instance that coordinates data cached by multiple cache peers,
76   * at a given time a cache peer may change data that is already cache at another peer. When doing so the last usage date
77   * for the token of cached data will be updated and the cache coordinator will be notified of this last usage change.</p>
78   * <p>Each cache peer holds its own copy of data, and the cache coordinator keeps a record of all
79   * last usage timestamp for every object at every cache peer. In this way, cached data is not be shared among peers,
80   * but it is kept synchronized by discarding all tokens witch timestamp at the peer is older than the one at the cache coordinator.</p>
81   * <p><b>UML</b></p>
82   * <img SRC="doc-files/DistributedCache-1.gif">
83   * @author Sergio Montoro Ten
84   * @version 1.1
85   * <br>
86   */
87  
88  public final class DistributedCachePeer {
89  
90    private Object   oCtx;  // javax.naming.Context
91    private Object   oDCC;  // cache.DistributedCacheCoordinator
92    private Object   oHome; // cache.DistributedCacheCoordinatorHome
93  
94    private LRUCachePolicy oCacheStore;
95    private Properties   oEnvProps;
96    private int iProviderProtocol;
97  
98    final private int PROTOCOL_NONE = -1;
99    final private int PROTOCOL_UNKNOWN = 0;
100   final private int PROTOCOL_HTTP = 1;
101   final private int PROTOCOL_HTTPS = 2;
102   final private int PROTOCOL_JNP = 3;
103 
104   /**
105    * <p>Create a local cache peer.</p>
106    * <p>The cache peer may be initialized to work in single-peer mode or in
107    * multi-peer mode with a cache coordinator.</p>
108    * <p>Initializacion properties for connecting with the cache coordinator
109    * when working in multi-peer mode are passed in appserver.cnf properties file.
110    * The appserver.cnf file is read using the singleton Environment object at
111    * com.knowgate.misc package.</p>
112    * <p>An example of a configuration file for JBoss may be as follows:</p>
113    * #DistributedCachePeer JBoss configuration file<br><br>
114    * #set this entry to "disabled" is working in single-peer mode<br>
115    * threetiers=enabled<br><br>
116    * java.naming.factory.initial=org.jnp.interfaces.NamingContextFactory<br>
117    * java.naming.provider.url=jnp://127.1.0.0:1099/<br>
118    * java.naming.factory.url.pkgs=org.jboss.naming:org.jnp.interfaces<br>
119    * jnp.socketFactory=org.jnp.interfaces.TimedSocketFactory<br>
120    * <p>An example of a configuration file for Tomcat may be as follows:</p>
121    * #DistributedCachePeer Tomcat configuration file<br><br>
122    * #set this entry to "disabled" is working in single-peer mode<br>
123    * threetiers=enabled<br><br>
124    * java.naming.factory.initial=<br>
125    * java.naming.provider.url=http://www.remotehost.com:1099/cache/server.jsp<br>
126    * java.naming.factory.url.pkgs=<br>
127    * jnp.socketFactory=<br>
128    * @throws InstantiationException
129    * @throws RemoteException
130    * @see Environment
131    */
132 
133   public DistributedCachePeer()
134     throws InstantiationException  ,RemoteException   {
135 
136     long lServerTime, lClientTime;
137     String   s3Tiers;
138 
139     if (DebugFile.trace) {
140       DebugFile.writeln("Begin DistributedCachePeer()");
141       DebugFile.incIdent();
142     }
143 
144     oCacheStore = new LRUCachePolicy(200, 400);
145 
146     oEnvProps = Environment.getProfile("appserver");
147     s3Tiers = oEnvProps.getProperty("threetiers", "disabled");
148 
149     /* Only test and debugging purposes ****************************************
150 
151     oEnvProps = new Properties();
152     oEnvProps.put("java.naming.factory.initial", "org.jnp.interfaces.NamingContextFactory");
153     oEnvProps.put("java.naming.provider.url", "jnp://server:1099/");
154     oEnvProps.put("java.naming.factory.url.pkgs", "org.jboss.naming:org.jnp.interfaces");
155     oEnvProps.put("jnp.socketFactory", "org.jnp.interfaces.TimedSocketFactory");
156 
157     ***************************************************************************/
158 
159     if (DebugFile.trace) {
160       DebugFile.writeln ("java.naming.factory.initial=" + oEnvProps.getProperty("java.naming.factory.initial",""));
161       DebugFile.writeln ("java.naming.provider.url=" + oEnvProps.getProperty("java.naming.provider.url",""));
162       DebugFile.writeln ("java.naming.factory.url.pkgs=" + oEnvProps.getProperty("java.naming.factory.url.pkgs",""));
163       DebugFile.writeln ("jnp.socketFactory=" + oEnvProps.getProperty("jnp.socketFactory",""));
164     }
165 
166     if (s3Tiers.equalsIgnoreCase("enabled") || s3Tiers.equalsIgnoreCase("yes") || s3Tiers.equalsIgnoreCase("true") || s3Tiers.equalsIgnoreCase("on") || s3Tiers.equals("1")) {
167 
168       String   sProviderURL = oEnvProps.getProperty("java.naming.provider.url","").toLowerCase();
169 
170       if (sProviderURL.startsWith("http://"))
171         iProviderProtocol = PROTOCOL_HTTP;
172       else if (sProviderURL.startsWith("https://"))
173         iProviderProtocol = PROTOCOL_HTTPS;
174       else if (sProviderURL.startsWith("jnp://"))
175         iProviderProtocol = PROTOCOL_JNP;
176       else
177         iProviderProtocol = PROTOCOL_UNKNOWN;
178 
179       if (PROTOCOL_HTTP!=iProviderProtocol && PROTOCOL_HTTPS!=iProviderProtocol) {
180 
181         try {
182 
183           if (DebugFile.trace) DebugFile.writeln ("Context oCtx = new InitialContext(Properties)");
184 
185           oCtx = new javax.naming.InitialContext  (oEnvProps);
186 
187           if (DebugFile.trace)
188             DebugFile.writeln("oHome = (DistributedCacheCoordinatorHome) oCtx.lookup(\"DistributedCacheCoordinator\")");
189 
190           oHome = ( (javax.naming.Context  ) oCtx).lookup("DistributedCacheCoordinator");
191 
192           if (DebugFile.trace)
193             DebugFile.writeln("DistributedCacheCoordinator = DistributedCacheCoordinatorHome.create()");
194 
195           oDCC = ( (com.knowgate.cache.server.DistributedCacheCoordinatorHome) oHome).create();
196 
197           // Sincronizar la fecha del cliente con la del servidor
198           lServerTime = ( (com.knowgate.cache.server.DistributedCacheCoordinator) oDCC).now();
199 
200           lClientTime = new Date  ().getTime();
201 
202           if (lClientTime < lServerTime) {
203             lServerTime = ( (com.knowgate.cache.server.DistributedCacheCoordinator) oDCC).now() + 1000;
204             Environment.updateSystemTime(lServerTime);
205           } // fi (lClientTime < lServerTime)
206         }
207         catch (javax.naming.NamingException   ne) {
208           throw new java.lang.InstantiationException  ("javax.naming.NamingException " + ne.getMessage() + " " + ne.getExplanation());
209         }
210         catch (javax.ejb.CreateException   ce) {
211           throw new java.lang.InstantiationException  ("javax.ejb.CreateException " + ce.getMessage());
212         }
213       } // fi (iProviderProtocol)
214       else
215         oDCC = null;
216     } // fi (threetiers)
217     else {
218       iProviderProtocol = PROTOCOL_NONE;
219     }
220 
221     if (DebugFile.trace) {
222       DebugFile.decIdent();
223       DebugFile.writeln("End new DistributedCachePeer()");
224     }
225 
226   } // DistributedCachePeer
227 
228   // ----------------------------------------------------------
229 
230   private static String   trim(String   s) {
231     if (null==s)
232       return null;
233     else
234       return (s.replace('\n',' ').replace('\r',' ').replace('\t',' ')).trim();
235   }
236 
237   // ----------------------------------------------------------
238 
239   /**
240    * Get an object from the cache peer.
241    * @param sTokenKey Token of object to be retrieved
242    * @return Reference to the requested object or <b>null</b> if object is not present at the local cache or it was modified by another cache peer.
243    * @throws RemoteException
244    */
245 
246   public Object   get(String   sTokenKey)
247     throws RemoteException  ,NullPointerException   {
248 
249     long lLastMod;
250     long lLastLocal;
251     Object   oRetSet = null;
252 
253     if (DebugFile.trace) {
254       DebugFile.writeln("Begin DistributedCachePeer.get(" + sTokenKey + ")");
255       DebugFile.incIdent();
256     }
257 
258     if (PROTOCOL_NONE==iProviderProtocol)
259       // Si no existe ning�n coordinador de cache distribuido configurado,
260       // tener en cuenta s�lo el cache local.
261       oRetSet = oCacheStore.get(sTokenKey);
262     else
263     {
264       // Recuperar la entrada del cache local
265       oRetSet = oCacheStore.get(sTokenKey);
266 
267       if (null!=oRetSet ) {
268         // Obtener la fecha de �ltima modificaci�n del coordinador de caches
269         if (PROTOCOL_HTTP==iProviderProtocol || PROTOCOL_HTTPS==iProviderProtocol) {
270 
271           String   sProviderURL = oEnvProps.getProperty("java.naming.provider.url");
272 
273           if (null==sProviderURL)
274             throw new NullPointerException  ("Property java.naming.provider.url not set at appserver.cnf");
275 
276           else {
277             String   sLastMod = "";
278 
279             try {
280               if (DebugFile.trace) DebugFile.writeln("new javax.activation.DataHandler(new URL(" + sProviderURL + "?method=get&key=" + sTokenKey + "))");
281 
282               javax.activation.DataHandler   oDataHndlr = new javax.activation.DataHandler  (new URL  (sProviderURL+"?method=get&key=" + sTokenKey));
283 
284                ByteArrayOutputStream   oURLBytes = new ByteArrayOutputStream  (128);
285                oDataHndlr.writeTo(oURLBytes);
286                sLastMod = trim(oURLBytes.toString());
287                oURLBytes.close();
288                oURLBytes = null;
289 
290                if (DebugFile.trace) DebugFile.writeln("lLastMod=" + sLastMod);
291 
292                lLastMod = Long.parseLong(sLastMod);
293             }
294             catch (MalformedURLException   badurl) {
295               if (DebugFile.trace) DebugFile.writeln("MalformedURLException " + sProviderURL + "?method=get&key=" + sTokenKey);
296 
297               throw new RemoteException  ("MalformedURLException " + sProviderURL + "?method=get&key=" + sTokenKey);
298             }
299             catch (IOException   badurl) {
300               if (DebugFile.trace) DebugFile.writeln("IOException " + sProviderURL + "?method=get&key=" + sTokenKey);
301 
302               throw new RemoteException  ("IOException " + sProviderURL + "?method=get&key=" + sTokenKey);
303             }
304             catch (NumberFormatException   nume) {
305               if (DebugFile.trace) DebugFile.writeln("NumberFormatException " + sLastMod);
306 
307               throw new RemoteException  ("NumberFormatException " + sLastMod);
308             }
309           }
310         }
311         else {
312           if (DebugFile.trace) DebugFile.writeln("DistributedCacheCoordinator.lastModified(" + sTokenKey + ")");
313 
314           lLastMod = ((com.knowgate.cache.server.DistributedCacheCoordinator) oDCC).lastModified(sTokenKey);
315 
316           if (DebugFile.trace) DebugFile.writeln("lLastMod=" + String.valueOf(lLastMod));
317         }
318 
319         lLastLocal = oCacheStore.last(sTokenKey);
320 
321         if (DebugFile.trace) {
322           if (lLastMod==0)
323             DebugFile.writeln(sTokenKey + " not found at distributed cache");
324           else
325             DebugFile.writeln(sTokenKey + " has timestamp " + new Date  (lLastMod).toString() + " at distributed cache");
326 
327           DebugFile.writeln(sTokenKey + " has timestamp " + new Date  (lLastLocal).toString() + " at local cache");
328         }
329 
330         if (lLastLocal>=lLastMod) {
331           // Si la fecha local es mayor o igual que la del coordinador, devolver la entrada local
332           if (DebugFile.trace) DebugFile.writeln("cache hit for " + sTokenKey);
333         }
334         else {
335           // Si la fecha local es anterior a la del coordinador, la entrada local ya no es v�lida
336           if (DebugFile.trace) DebugFile.writeln("cache outdated for " + sTokenKey);
337           oCacheStore.remove(sTokenKey);
338           oRetSet = null;
339         }
340       } // fi(oEntry)
341       else {
342         if (DebugFile.trace) DebugFile.writeln("cache miss for " + sTokenKey);
343       }
344     } // fi(oDCC)
345 
346     if (DebugFile.trace) {
347       DebugFile.decIdent();
348       DebugFile.writeln("End DistributedCachePeer.get()");
349     }
350 
351     return oRetSet;
352   } // getDBSubset
353 
354   // ----------------------------------------------------------
355 
356   /**
357    * @return Same as DistributedCachePeer.get() but cast returned object to a {@link DBSubset}.
358    * @throws ClassCastException
359    */
360   public DBSubset getDBSubset(String   sTokenKey) throws RemoteException  ,ClassCastException   {
361     Object   oObj = get (sTokenKey);
362 
363     if (null==oObj)
364       return null;
365     else
366       return (DBSubset) get(sTokenKey);
367   } // getDBSubset
368 
369   // ----------------------------------------------------------
370 
371   /**
372    * @param sTokenKey Token of object to be retrieved
373    * @return Same as DistributedCachePeer.get() but cast returned object to a String.
374    * @throws ClassCastException
375    */
376   public String   getString(String   sTokenKey) throws RemoteException  ,ClassCastException   {
377     Object   oObj = get (sTokenKey);
378     if (null==oObj)
379       return null;
380     else
381       return (String  ) oObj;
382   } // getString
383 
384   // ----------------------------------------------------------
385 
386   /**
387    * @param sTokenKey Token of object to be retrieved
388    * @throws ClassCastException
389    */
390   public Boolean   getBoolean(String   sTokenKey) throws RemoteException  , ClassCastException   {
391     Object   oObj = get (sTokenKey);
392     if (null==oObj)
393       return null;
394     else
395       return (Boolean  ) oObj;
396   } // getBoolean
397 
398   // ----------------------------------------------------------
399 
400   /**
401    * Return keys for entries in cache
402    * @return Set of keys (Strings)
403    */
404 
405   public java.util.Set   keySet() {
406 
407     return oCacheStore.keySet();
408   }
409 
410   // ----------------------------------------------------------
411 
412   /**
413    * <p>Puts an Object into local cache.</p>
414    * @param sTokenKey Token for object
415    * @param oObj Object to be stored.
416    * @throws RemoteException
417    * @throws IllegalArgumentException If either sTokenKey or oObj is <b>null</b>.
418    * @throws IllegalStateException If object with given token is already present at local cache.
419    */
420   public void put(String   sTokenKey, Object   oObj)
421     throws IllegalStateException  , IllegalArgumentException  , RemoteException   {
422     long lDtServerModified;
423 
424     if (DebugFile.trace) {
425       DebugFile.writeln("Begin DistributedCachePeer.put(" + sTokenKey + ", ...)");
426       DebugFile.incIdent();
427     }
428 
429     if (PROTOCOL_NONE==iProviderProtocol)
430 
431       lDtServerModified = System.currentTimeMillis();
432 
433     else if (PROTOCOL_HTTP==iProviderProtocol || PROTOCOL_HTTPS==iProviderProtocol) {
434 
435       String   sProviderURL = oEnvProps.getProperty("java.naming.provider.url");
436 
437       if (null == sProviderURL)
438         throw new NullPointerException  ("Property java.naming.provider.url not set at appserver.cnf");
439 
440       else {
441         String   sServerMod = "";
442 
443         try {
444           if (DebugFile.trace) DebugFile.writeln("new javax.activation.DataHandler(new URL(" + sProviderURL + "?method=put&key=" + sTokenKey + "))");
445 
446           javax.activation.DataHandler   oDataHndlr = new javax.activation.DataHandler  (new URL  (sProviderURL + "?method=put&key=" + sTokenKey));
447 
448           ByteArrayOutputStream   oURLBytes = new ByteArrayOutputStream  (128);
449           oDataHndlr.writeTo(oURLBytes);
450           sServerMod = trim(oURLBytes.toString());
451           oURLBytes.close();
452           oURLBytes = null;
453 
454           if (DebugFile.trace) DebugFile.writeln("lDtServerModified=" + sServerMod);
455 
456           lDtServerModified = Long.parseLong(sServerMod);
457         }
458         catch (MalformedURLException   badurl) {
459           if (DebugFile.trace) DebugFile.writeln("MalformedURLException " + sProviderURL + "?method=get&put=" + sTokenKey);
460 
461           throw new RemoteException  ("MalformedURLException " + sProviderURL + "?method=put&key=" + sTokenKey);
462         }
463         catch (IOException   badurl) {
464           if (DebugFile.trace) DebugFile.writeln("IOException " + sProviderURL + "?method=get&put=" + sTokenKey);
465 
466           throw new RemoteException  ("IOException " + sProviderURL + "?method=get&put=" + sTokenKey);
467         }
468         catch (NumberFormatException   nume) {
469           if (DebugFile.trace) DebugFile.writeln("NumberFormatException " + sServerMod);
470 
471           throw new RemoteException  ("NumberFormatException " + sServerMod);
472         }
473       }
474     }
475     else {
476 
477       if (DebugFile.trace) DebugFile.writeln("DistributedCacheCoordinator.modify(" + sTokenKey + ")");
478 
479       lDtServerModified = ((com.knowgate.cache.server.DistributedCacheCoordinator) oDCC).modify(sTokenKey);
480 
481       if (DebugFile.trace) DebugFile.writeln("lDtServerModified=" + String.valueOf(lDtServerModified));
482 
483     }
484 
485     if (DebugFile.trace) DebugFile.writeln("LRUCachePolicy.insert(" + sTokenKey + ", [Object], " + String.valueOf(lDtServerModified));
486 
487     oCacheStore.insert (sTokenKey, oObj, lDtServerModified);
488 
489     if (DebugFile.trace) {
490       DebugFile.decIdent();
491       DebugFile.writeln("End DistributedCachePeer.put()");
492     }
493   } // put
494 
495   // ----------------------------------------------------------
496 
497   /**
498    * <p>Puts a DBSubset into local cache.</p>
499    * @param sTokenKey Token for object
500    * @param oObj Object to be stored.
501    * @throws RemoteException
502    * @throws IllegalArgumentException If either sTokenKey or oObj is <b>null</b>.
503    * @throws IllegalStateException If object with given token is already present at local cache.
504    */
505   public void putDBSubset(String   sTableName, String   sTokenKey, DBSubset oDBSS) throws RemoteException   {
506     if (DebugFile.trace) {
507       DebugFile.writeln("Begin DistributedCachePeer.putDBSubset(" + sTokenKey + ", ...)");
508       DebugFile.incIdent();
509     }
510 
511     put (sTokenKey, oDBSS);
512 
513     if (DebugFile.trace) {
514       DebugFile.decIdent();
515       DebugFile.writeln("End DistributedCachePeer.putDBSubset()");
516     }
517   } // putDBSubset
518 
519   // ----------------------------------------------------------
520 
521   /**
522    * <b>Removes an Object from the cache and notify other cache peers that
523    * the objects with the given token should no longer be considered valid.</p>
524    * If Object with given token was not present at cache no error is raised.
525    * @param sTokenKey Token of object to be removed from local cache.
526    * @throws RemoteException
527    * @throws IllegalArgumentException If sTkeney is <b>null</b>.
528    * @throws IllegalStateException If local cache is empty.
529    */
530   public void expire(String   sTokenKey) throws IllegalArgumentException  , RemoteException   {
531     if (DebugFile.trace) {
532       DebugFile.writeln("Begin DistributedCachePeer.expire(" + sTokenKey + ")");
533       DebugFile.incIdent();
534     }
535     if (PROTOCOL_NONE!=iProviderProtocol) {
536 
537       if (PROTOCOL_HTTP==iProviderProtocol || PROTOCOL_HTTPS==iProviderProtocol) {
538 
539         String   sProviderURL = oEnvProps.getProperty("java.naming.provider.url");
540 
541         if (null==sProviderURL)
542           throw new NullPointerException  ("Property java.naming.provider.url not set at appserver.cnf");
543 
544         else {
545 
546           try {
547 
548             if (DebugFile.trace) DebugFile.writeln("new javax.activation.DataHandler(new URL(" + sProviderURL + "?method=expire&key=" + sTokenKey + "))");
549 
550             javax.activation.DataHandler   oDataHndlr = new javax.activation.DataHandler  (new URL  (sProviderURL+"?method=expire&key=" + sTokenKey));
551 
552              ByteArrayOutputStream   oURLBytes = new ByteArrayOutputStream  (128);
553              oDataHndlr.writeTo(oURLBytes);
554              oURLBytes.close();
555              oURLBytes = null;
556 
557           }
558           catch (MalformedURLException   badurl) {
559             throw new RemoteException  ("MalformedURLException " + sProviderURL + "?method=expire&key=" + sTokenKey);
560           }
561           catch (IOException   badurl) {
562             throw new RemoteException  ("IOException " + sProviderURL + "?method=get&key=" + sTokenKey);
563           }
564         } // fi (null!=sProviderURL)
565       }
566       else {
567         if (DebugFile.trace) DebugFile.writeln("DistributedCacheCoordinator.expire(" + sTokenKey + ")");
568 
569         ((com.knowgate.cache.server.DistributedCacheCoordinator) oDCC).expire(sTokenKey);
570       }
571     }
572     oCacheStore.remove(sTokenKey);
573 
574     if (DebugFile.trace) {
575       DebugFile.decIdent();
576       DebugFile.writeln("End DistributedCachePeer.expire()");
577     }
578   } // expire
579 
580   // ----------------------------------------------------------
581 
582   /**
583    * <p>Remove all objects from local cache and expire then and cache coordinator.</p>
584    * @throws RemoteException
585    */
586   public void expireAll() throws RemoteException   {
587     if (DebugFile.trace) {
588       DebugFile.writeln("Begin DistributedCachePeer.expireAll()");
589       DebugFile.incIdent();
590     }
591     Iterator   oKeys;
592 
593     if (PROTOCOL_NONE!=iProviderProtocol) {
594 
595       oKeys = oCacheStore.m_map.keySet().iterator();
596 
597       while(oKeys.hasNext()) expire((String  ) oKeys.next());
598 
599     } // fi (oDCC)
600 
601     oCacheStore.flush();
602 
603     if (DebugFile.trace) {
604       DebugFile.decIdent();
605       DebugFile.writeln("End DistributedCachePeer.expireAll()");
606     }
607   } // expireAll
608 
609   // ----------------------------------------------------------
610 
611   /**
612    * <p>Number of entries in cache</p>
613    */
614   public int size() {
615     return oCacheStore.size();
616   }
617 } // DistributedCachePeer
618
A to Z: JavaDoc & Examples Daily Java News & Articles Open Source Projects Open Source Codes Free Computer Books Remove Frame
Free Books Free Magazines
Popular Tags