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Java > Open Source Codes > org > apache > jetspeed > services > portletcache > JetspeedPortletCacheService


1 /*
2  * Copyright 2000-2001,2004 The Apache Software Foundation.
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  * http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */

16
17 package org.apache.jetspeed.services.portletcache;
18
19 import javax.servlet.ServletConfig JavaDoc;
20
21 // Jetspeed
22
import org.apache.jetspeed.portal.portlets.AbstractPortlet;
23 import org.apache.jetspeed.services.logging.JetspeedLogFactoryService;
24 import org.apache.jetspeed.services.logging.JetspeedLogger;
25 import org.apache.jetspeed.services.resources.JetspeedResources;
26 import org.apache.jetspeed.services.portletcache.Cacheable;
27
28 // Turbine
29
import org.apache.turbine.services.TurbineBaseService;
30 import org.apache.turbine.services.TurbineServices;
31 import org.apache.turbine.services.cache.CachedObject;
32 import org.apache.turbine.services.cache.Refreshable;
33 import org.apache.turbine.services.cache.RefreshableCachedObject;
34 import org.apache.turbine.services.cache.ObjectExpiredException;
35
36
37 /**
38  * <P>This implementation of the PortletCache service is a simple adapter to
39  * the Turbine GlobalCacheService</p>
40  *
41  * @author <a HREF="mailto:burton@apache.org">Kevin A. Burton</a>
42  * @author <a HREF="mailto:raphael@apache.org">RaphaŽl Luta</a>
43  * @author <a HREF="mailto:paulsp@apache.org">Paul Spencer</a>
44  * @version $Id: JetspeedPortletCacheService.java,v 1.10 2004/02/23 03:34:54 jford Exp $
45  */

46 public class JetspeedPortletCacheService
47 extends TurbineBaseService
48 implements PortletCacheService
49 {
50     /**
51      * Static initialization of the logger for this class
52      */

53     private static final JetspeedLogger logger = JetspeedLogFactoryService.getLogger(JetspeedPortletCacheService.class.getName());
54     
55     private static int DefaultTimeToLiveMillis = (JetspeedResources.getInt(TurbineServices.SERVICE_PREFIX
56     + PortletCacheService.SERVICE_NAME
57     + ".TimeToLive.default", (30 * 60 * 1000))); // 30 minutes
58

59     /**
60      * Called during Turbine.init()
61      *
62      * @param config A ServletConfig.
63      */

64     public void init( ServletConfig JavaDoc config ) {
65         try {
66             logger.info( "JetspeedPortletCacheService early init()....starting!");
67             if (DefaultTimeToLiveMillis < 0) {
68                 logger.info( "JetspeedPortletCacheService - By default refreshable objects will live for ever");
69             } else {
70                 logger.info( "JetspeedPortletCacheService - By default refreshable objects will be removed after "
71                 + DefaultTimeToLiveMillis + " Millis ( "
72                 + (DefaultTimeToLiveMillis/(1000*60)) + " minutes "
73                 + ((DefaultTimeToLiveMillis%(1000*60))/1000.00)
74                 + " Seconds "+")" );
75             }
76             // no specific init required, relies on GlobalCacheService
77
logger.info( "JetspeedPortletCacheService early init()....finished!");
78         }
79         catch (Exception JavaDoc e) {
80             logger.error( "Cannot initialize JetspeedPortletCacheService!", e );
81         }
82         setInit(true);
83     }
84     
85     /**
86      * Add a Cacheable object to the cache.
87      *
88      * @param item the object to store in the Cache
89      */

90     public void addCacheable( Cacheable item ) {
91         
92         String JavaDoc handle = item.getHandle();
93         
94         if ( handle.length() == 0 ) {
95             throw new RuntimeException JavaDoc("You must specify a handle for the item you want to cache.");
96         }
97         
98         if ( item.isCacheable() ) {
99             CachedObject cachedObject = null;
100             Long JavaDoc expirationMillis = item.getExpirationMillis();
101             if (expirationMillis != null) {
102                 if (System.currentTimeMillis() < expirationMillis.longValue()) {
103                     cachedObject.setExpires(expirationMillis.longValue() - cachedObject.getCreated());
104                 }
105             }
106             if (item instanceof Refreshable) {
107                 RefreshableCachedObject rco = new RefreshableCachedObject( (Refreshable) item);
108                 if (item instanceof AbstractPortlet) {
109                     AbstractPortlet portlet = (AbstractPortlet)item;
110                     String JavaDoc tempString = portlet.getPortletConfig().getInitParameter(JetspeedResources.TIME_TO_LIVE);
111                     if (tempString != null) {
112                         rco.setTTL(Integer.parseInt(tempString));
113                         if (logger.isWarnEnabled())
114                         {
115                             logger.warn("PortletCache: portlet "
116                                      + item.getHandle()
117                                      + " overrides default time to live with "
118                                      + tempString);
119                         }
120                     } else {
121                         rco.setTTL(DefaultTimeToLiveMillis);
122                     }
123                 } else {
124                     rco.setTTL(DefaultTimeToLiveMillis);
125                 }
126                 cachedObject = rco;
127                 
128             } else {
129                 cachedObject = new CachedObject(item);
130             }
131             item.setCachedObject(cachedObject);
132
133             // Add object to cache
134
GlobalCache.addObject( handle , cachedObject);
135          }
136     }
137     
138     /**
139      * Removes an object from the cache based on its handle
140      *
141      * @see PortletCacheService#removeCacheable
142      * @param handle the identifier of the object we wish to retrieve
143      */

144     public void removeCacheable( String JavaDoc handle ) {
145         
146         CachedObject obj = null;
147         
148         try {
149             obj = GlobalCache.getObject( handle );
150         } catch ( ObjectExpiredException e) {
151             // nothing to do if already expired
152
}
153         
154         if ( obj != null ) {
155             obj.setStale(true);
156         }
157     }
158     
159     /**
160      * Retrieves a Cacheable object from the cache.
161      *
162      * @param handle the identifier of the object we wish to retrieve
163      * @return the cacehd object or null if not found
164      */

165     public Cacheable getCacheable( String JavaDoc handle ) {
166         
167         CachedObject obj = null;
168         
169         try {
170             obj = GlobalCache.getObject( handle );
171         } catch (ObjectExpiredException e) {
172             logger.info( "cache miss, object expired: " + handle );
173         }
174         
175         if ( obj == null ) {
176             //Log.info( "cache miss: " + handle );
177
return null;
178         } /*else {
179             Log.info( "cache hit: " + handle );
180             } */

181         
182         return (Cacheable)obj.getContents();
183         
184     }
185     
186 }
187
188
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