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1
4 package org.roller.presentation.filters;
5
6 import org.apache.commons.lang.StringUtils;
7 import org.apache.commons.logging.Log;
8 import org.apache.commons.logging.LogFactory;
9 import org.roller.RollerException;
10 import org.roller.model.Roller;
11 import org.roller.model.WeblogManager;
12 import org.roller.pojos.UserData;
13 import org.roller.presentation.RollerContext;
14 import org.roller.presentation.RollerRequest;
15 import org.roller.util.LRUCache2;
16
17 import java.io.IOException  ;
18 import java.text.SimpleDateFormat ;
19 import java.util.Date ;
20
21 import javax.servlet.Filter ;
22 import javax.servlet.FilterChain ;
23 import javax.servlet.FilterConfig ;
24 import javax.servlet.ServletException ;
25 import javax.servlet.ServletRequest ;
26 import javax.servlet.ServletResponse ;
27 import javax.servlet.http.HttpServletRequest ;
28 import javax.servlet.http.HttpServletResponse ;
29 import org.roller.config.RollerConfig;
30
31
47 public class IfModifiedFilter implements Filter
48 {
49 private static Log mLogger =
50 LogFactory.getFactory().getInstance(IfModifiedFilter.class);
51
52 private static int mCacheSize = 300;
54 private static int mCacheTime = 1800;
55 private static LRUCache2 mDateCache = null;
56 SimpleDateFormat dateFormatter =
57 new SimpleDateFormat ("EEE MMM d HH:mm:ss z yyyy");
58
59 public IfModifiedFilter()
60 {
61 super();
62 }
63
64
67 public void init(FilterConfig filterConfig) throws ServletException
68 {
69 mLogger.debug("Initializing IfModified Filter");
70
71 String cacheSizeString = RollerConfig.getProperty("cache.filter.ifmodified.size");
72 String cacheTimeString = RollerConfig.getProperty("cache.filter.ifmodified.timeout");
73
74 try
75 {
76 if (cacheSizeString != null) mCacheSize = Integer.parseInt(cacheSizeString);
77 }
78 catch (Throwable e)
79 {
80 mLogger.warn("ERROR parsing cache size");
81 }
82 try
83 {
84 if (cacheTimeString != null) mCacheTime = Integer.parseInt(cacheTimeString);
85 }
86 catch (Throwable e)
87 {
88 mLogger.warn("ERROR parsing cache time");
89 }
90
91 mLogger.info("cache size is: "+mCacheSize);
92 mLogger.info("cache timeout is: "+mCacheTime);
93
94 mDateCache = new LRUCache2(mCacheSize, mCacheTime*60*1000);
95 }
96
97
101 private static LRUCache2 getCache()
102 {
103 if (mDateCache == null)
104 {
105 mDateCache = new LRUCache2(mCacheSize, mCacheTime*60*1000);
106 }
107 return mDateCache;
108 }
109
110
116 public void doFilter(
117 ServletRequest req,
118 ServletResponse res,
119 FilterChain chain)
120 throws IOException , ServletException
121 {
122 HttpServletRequest request = (HttpServletRequest ) req;
123 HttpServletResponse response = (HttpServletResponse ) res;
124
125 Date updateTime = null;
126 try
127 {
128 updateTime = getLastPublishedDate(request);
129
130 request.setAttribute("updateTime", updateTime);
132
133 Date sinceDate =
135 new Date (request.getDateHeader("If-Modified-Since"));
136
137 if (updateTime != null)
138 {
139 String date = dateFormatter.format(updateTime);
141 updateTime = new Date (date);
142 if (updateTime.compareTo(sinceDate) <= 0)
143 {
144 response.setStatus(HttpServletResponse.SC_NOT_MODIFIED);
145 return;
146 }
147 }
148 mLogger.debug("Not returning 304 for: "+request.getRequestURI());
149 }
150 catch (RollerException e)
151 {
152 response.setStatus(HttpServletResponse.SC_BAD_REQUEST);
154 return;
155 }
156 catch (IllegalArgumentException e)
157 {
158 }
162
163 if (updateTime != null)
165 {
166 response.setDateHeader("Last-Modified", updateTime.getTime());
167 }
168
169 chain.doFilter(request, response);
170 }
171
172 public static Date getLastPublishedDate(HttpServletRequest request)
173 throws RollerException
174 {
175 String userName = null;
177 String pathInfo = request.getPathInfo();
178 pathInfo = pathInfo != null ? pathInfo : "";
179 String [] pathInfoArray = StringUtils.split(pathInfo, "/");
180 if (pathInfoArray.length == 1)
181 {
182 userName = pathInfoArray[0];
183 }
184 else if (pathInfoArray.length > 1)
185 {
186 return null;
188 }
189
190 String catname =
192 request.getParameter(RollerRequest.WEBLOGCATEGORYNAME_KEY);
193
194 StringBuffer sb = new StringBuffer ();
196 sb.append("zzz_");
197 sb.append(userName);
198 sb.append("_zzz_");
199 sb.append(catname);
200 String key = sb.toString();
201
202 Date updateTime = (Date )getCache().get(key);
203 if (updateTime == null)
204 {
205 mLogger.debug("Hitting database for update time: "+key);
206 Roller roller = RollerContext.getRoller(request);
207 WeblogManager wmgr = roller.getWeblogManager();
208 updateTime = wmgr.getWeblogLastPublishTime(userName, catname);
209 getCache().put(key, updateTime);
210 }
211 return updateTime;
212 }
213
214 public static void purgeDateCache(UserData user)
215 {
216 String userName = (user != null) ? user.getUserName() : null;
217 StringBuffer sb = new StringBuffer ();
218 sb.append("zzz_");
219 sb.append(userName);
220 sb.append("_zzz_");
221 getCache().purge(new String [] {sb.toString()});
222 }
223
224
227 public void destroy()
228 {
229 }
230 }
231 |
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