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1
24 package org.riotfamily.cachius;
25
26 import java.io.BufferedInputStream  ;
27 import java.io.BufferedReader ;
28 import java.io.File ;
29 import java.io.FileInputStream ;
30 import java.io.FileNotFoundException ;
31 import java.io.IOException ;
32 import java.io.InputStream ;
33 import java.io.InputStreamReader ;
34 import java.io.ObjectInputStream ;
35 import java.io.Reader ;
36 import java.io.Serializable ;
37 import java.io.Writer ;
38 import java.util.Arrays ;
39
40 import javax.servlet.ServletResponse ;
41 import javax.servlet.http.HttpServletRequest ;
42
43 import org.apache.commons.logging.Log;
44 import org.apache.commons.logging.LogFactory;
45 import org.riotfamily.cachius.support.ReaderWriterLock;
46 import org.riotfamily.cachius.support.TokenFilterWriter;
47 import org.riotfamily.common.io.IOUtils;
48
49
50
67 public class CacheItem implements Serializable {
68
69 private static final String ITEM_PREFIX = "item";
70
71 private static final String TEMP_PREFIX = "tmp";
72
73 private static final String TEMPFILE_SUFFIX = "";
74
75 private static final long NOT_YET = -1L;
76
77 private static final String FILE_ENCODING = "UTF-8";
78
79 private Log log = LogFactory.getLog(CacheItem.class);
80
81
82 private transient CacheItem previous;
83
84
85 private transient CacheItem next;
86
87
88 private String key;
89
90
91 private String [] tags;
92
93
94 private boolean filterSessionId;
95
96
97 private File file = null;
98
99
100 private String contentType = null;
101
102
106 private boolean binary = true;
107
108
112 private transient ReaderWriterLock lock = new ReaderWriterLock();
113
114
117 private long lastModified;
118
119
122 private long lastCheck;
123
124 public CacheItem(String key, File cacheDir) throws IOException {
125 this.key = key;
126 file = File.createTempFile(ITEM_PREFIX, TEMPFILE_SUFFIX, cacheDir);
127 lastModified = NOT_YET;
128 }
129
130 public String getKey() {
131 return key;
132 }
133
134 public void setKey(String key) {
135 this.key = key;
136 }
137
138 public void setTags(String [] tags) {
139 if (tags != null) {
140 Arrays.sort(tags);
141 }
142 this.tags = tags;
143 }
144
145 public String [] getTags() {
146 return tags;
147 }
148
149 public boolean hasTag(String tag) {
150 return tags != null && Arrays.binarySearch(tags, tag) >= 0;
151 }
152
153 public CacheItem getPrevious() {
154 return previous;
155 }
156
157
158 public void setPrevious(CacheItem previous) {
159 this.previous = previous;
160 }
161
162 public CacheItem getNext() {
163 return next;
164 }
165
166 public void setNext(CacheItem next) {
167 this.next = next;
168 }
169
170 public int hashCode() {
171 return key.hashCode();
172 }
173
174 public boolean isFilterSessionId() {
175 return filterSessionId;
176 }
177
178 public void setFilterSessionId(boolean filterSessionId) {
179 this.filterSessionId = filterSessionId;
180 }
181
182 public void setContentType(String contentType) {
183 this.contentType = contentType;
184 }
185
186 public String getContentType() {
187 return contentType;
188 }
189
190 public long getLastModified() {
191 return lastModified;
192 }
193
194 public void setLastModified(long lastModified) {
195 this.lastModified = lastModified;
196 }
197
198 public long getLastCheck() {
199 return this.lastCheck;
200 }
201
202 public void setLastCheck(long lastCheck) {
203 this.lastCheck = lastCheck;
204 }
205
206 public boolean isNew() {
207 return lastModified == NOT_YET;
208 }
209
210
213 public boolean exists() {
214 return file != null && file.isFile();
215 }
216
217 public File createTempFile() throws IOException {
218 File dir = file.getParentFile();
219 dir.mkdirs();
220 return File.createTempFile(TEMP_PREFIX, TEMPFILE_SUFFIX, dir);
221 }
222
223 public void update(File tempFile, boolean binary) {
224 log.debug("Updating cached version of " + key);
225 try {
226 lock.lockForWriting();
227 lastModified = System.currentTimeMillis();
228 delete();
229 IOUtils.move(tempFile, file);
230 this.binary = binary;
231 }
232 finally {
233 lock.releaseWriterLock();
234 }
235 }
236
237 public void writeTo(HttpServletRequest request,
238 ServletResponse response) throws IOException {
239
240 log.debug("Serving cached version of " + key);
241 try {
242 lock.lockForReading();
243 if (contentType != null) {
244 response.setContentType(contentType);
245 }
246
247 if (binary) {
248 InputStream in = new BufferedInputStream (
249 new FileInputStream (file));
250
251 IOUtils.copy(in, response.getOutputStream());
252 }
253 else {
254 Reader in = new BufferedReader (new InputStreamReader (
255 new FileInputStream (file), FILE_ENCODING));
256
257 Writer out = response.getWriter();
258 if (filterSessionId) {
259 out = new TokenFilterWriter("${jsessionid}",
260 request.getSession().getId(), out);
261 }
262
263 IOUtils.copy(in, out);
264 }
265 }
266 catch (FileNotFoundException e) {
267 log.warn("Cache file not found. Resetting modification time " +
268 "to trigger update on next request.");
269
270 lastModified = NOT_YET;
271 }
272 finally {
273 lock.releaseReaderLock();
274 }
275 }
276
277 public void invalidate() {
278 lastModified = NOT_YET;
279 delete();
280 }
281
282 public void delete() {
283 if (file.exists()) {
284 if (!file.delete()) {
285 log.warn("Failed to delete cache file: " + file);
286 }
287 }
288 }
289
290
293 private void readObject(ObjectInputStream in) throws IOException ,
294 ClassNotFoundException {
295
296 in.defaultReadObject();
297 lock = new ReaderWriterLock();
298 }
299
300 }
301 |
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