001 /*
002 * Copyright 2001-2004 The Apache Software Foundation
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 * http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016 package org.apache.commons.cache.tagext;
017
018 import javax.servlet.*;
019 import javax.servlet.http.*;
020 import javax.servlet.jsp.*;
021 import javax.servlet.jsp.tagext.*;
022 import java.io.*;
023 import java.util.Hashtable;
024 import org.apache.commons.cache.*;
025 import org.apache.commons.jocl.JOCLContentHandler;
026
027 /**
028 * ...tk...
029 * @version $Id: CacheTag.java 155435 2005-02-26 13:17:27Z dirkv $
030 * @author Rodney Waldhoff
031 */
032 public class CacheTag extends BodyTagSupport {
033 private static final boolean DEBUG = false;
034 private static final boolean VERBOSE_DEBUG = DEBUG && false;
035 private static final boolean CHECKING = false;
036
037 protected Serializable _key = null;
038 protected Serializable _group = null;
039 protected Long _expiresAt = null;
040 protected static Cache _cache = null;
041 protected String _content = null;
042 protected boolean _mustRevalidate = false;
043 protected String _name = null;
044
045 public void release() {
046 super.release();
047 _key = null;
048 _group = null;
049 _name = null;
050 _expiresAt = null;
051 _content = null;
052 _mustRevalidate = false;
053 }
054
055 public void setMustRevalidate(String obj) {
056 _mustRevalidate = Boolean.valueOf(obj).booleanValue();
057 }
058
059 // weblogic reflection doesn't work very well
060 /*
061 public void setMustRevalidate(Object obj) {
062 if(obj instanceof Boolean) {
063 _mustRevalidate = ((Boolean)obj).booleanValue();
064 } else {
065 _mustRevalidate = Boolean.valueOf(String.valueOf(obj)).booleanValue();
066 }
067 }
068 */
069 public void setMustRevalidate(boolean val) {
070 _mustRevalidate = val;
071 }
072
073 public void setName(String name) {
074 _name = name;
075 }
076
077 public void setGroup(String group) {
078 _group = group;
079 }
080
081 // weblogic reflection doesn't work very well
082 /*
083 public void setGroup(Serializable group) {
084 _group = group;
085 }
086 */
087
088 public void setKey(String key) {
089 _key = key;
090 }
091
092 // weblogic reflection doesn't work very well
093 /*
094 public void setKey(Serializable key) {
095 _key = key;
096 }
097 */
098
099 public void setTtl(String ttl) {
100 if(ttl != null) {
101 if(ttl.endsWith("s") || ttl.endsWith("S")) {
102 setTtl(1000L * Long.parseLong(ttl.substring(0,ttl.length() - 1)));
103 } else if(ttl.endsWith("m") || ttl.endsWith("M")) {
104 setTtl(60L * 1000L * Long.parseLong(ttl.substring(0,ttl.length() - 1)));
105 } else if(ttl.endsWith("h") || ttl.endsWith("H")) {
106 setTtl(60L * 60L * 1000L * Long.parseLong(ttl.substring(0,ttl.length() - 1)));
107 } else if(ttl.endsWith("d") || ttl.endsWith("D")) {
108 setTtl(24L * 60L * 60L * 1000L * Long.parseLong(ttl.substring(0,ttl.length() - 1)));
109 } else {
110 setTtl(1000L * Long.parseLong(ttl));
111 }
112 }
113 }
114
115 private void setTtl(long ttl) {
116 _expiresAt = new Long(System.currentTimeMillis() + ttl);
117 }
118
119 private void setTtl(Long ttl) {
120 if(null == ttl) {
121 _expiresAt = null;
122 } else {
123 _expiresAt = new Long(System.currentTimeMillis() + ttl.longValue());
124 }
125 }
126
127 public void setLastModified(String lastmodstr) {
128 long lastmod = 0L;
129 try {
130 lastmod = Long.parseLong(lastmodstr);
131 _expiresAt = new Long( System.currentTimeMillis() + ((System.currentTimeMillis() - lastmod)/2) );
132 } catch(Exception e) {
133 // do something?
134 _expiresAt = null;
135 }
136 }
137
138 // weblogic reflection doesn't work very well
139 /*
140 public void setLastModified(long lastmod) {
141 _expiresAt = new Long( System.currentTimeMillis() + ((System.currentTimeMillis() - lastmod)/2) );
142 }
143
144 public void setLastModified(Long lastmod) {
145 if(null != lastmod) {
146 _expiresAt = new Long( System.currentTimeMillis() + ((System.currentTimeMillis() - lastmod.longValue())/2) );
147 } else {
148 _expiresAt = null;
149 }
150 }
151 */
152 public void setExpiresAt(String expires) {
153 try {
154 _expiresAt = new Long(Long.parseLong(expires));
155 } catch(Exception e) {
156 // do something?
157 _expiresAt = null;
158 }
159 }
160
161 // weblogic reflection doesn't work very well
162 /*
163 public void setExpiresAt(long expires) {
164 _expiresAt = new Long(expires);
165 }
166
167 public void setExpiresAt(Long expires) {
168 _expiresAt = expires;
169 }
170 */
171 public int doStartTag() throws JspException {
172 if(!_mustRevalidate) {
173 try {
174 Object obj = getCache(_name).retrieve(_key);
175 if(null == obj) {
176 return EVAL_BODY_TAG;
177 } else {
178 _content = obj.toString();
179 return SKIP_BODY;
180 }
181 } catch(Exception e) {
182 e.printStackTrace();
183 throw new JspException(e.toString());
184 }
185 } else {
186 getCache(_name).clear(_key);
187 return EVAL_BODY_TAG;
188 }
189 }
190
191 public int doAfterBody() throws JspException {
192 _content = getBodyContent().getString();
193 getCache(_name).store(_key,_content,_expiresAt,null,_group);
194 return SKIP_BODY;
195 }
196
197 public int doEndTag() throws JspException {
198 try {
199 pageContext.getOut().write(_content);
200 } catch(Exception e) {
201 e.printStackTrace();
202 throw new JspException(e.toString());
203 }
204 return EVAL_PAGE;
205 }
206
207 private static final CacheTag _instance = new CacheTag(); // used in getCache
208
209 public synchronized static Cache getCache(String name) throws JspException {
210 if(CacheSingleton.hasCache(name)) {
211 return CacheSingleton.getCache(name);
212 } else {
213 Cache cache = null;
214
215 String serfile = System.getProperty("org.apache.commons.cache.tagext.CacheTag.cache." + name + ".serialized-cache-file");
216 if(null != serfile) {
217 try {
218 cache = SimpleCache.readFromFile(serfile);
219 } catch(Exception e) {
220 cache = null;
221 }
222 }
223
224 if(null != cache) {
225 CacheSingleton.putCache(name,cache);
226 return cache;
227 } else {
228 String config = System.getProperty("org.apache.commons.cache.tagext.CacheTag.cache." + name + ".configuration");
229 if(null == config) {
230 throw new JspException("Cache \"" + name + "\" not found.");
231 } else {
232 try {
233 JOCLContentHandler jocl = JOCLContentHandler.parse(_instance.getClass().getClassLoader().getResourceAsStream(config));
234 cache = (Cache)(jocl.getValue(0));
235 CacheSingleton.putCache(name,cache);
236 return cache;
237 } catch(Exception e) {
238 e.printStackTrace();
239 throw new JspException(e.toString());
240 }
241 }
242 }
243 }
244 }
245 }