Mercurial > hg > digilib-old
annotate servlet/src/digilib/io/DocuDirCache.java @ 286:07bb7d594477 Root_gen2
Servlet version 1.22b1
- more fast searching (hopefully all working now)
- some simple synchronisation
- some reshuffling of methods to eliminate cruft
| author | robcast |
|---|---|
| date | Fri, 15 Oct 2004 17:00:15 +0200 |
| parents | 87dca7119596 |
| children | dd1e681924bf |
| rev | line source |
|---|---|
| 176 | 1 /* |
| 2 * DocuDirCache.java | |
| 3 * | |
| 4 * Digital Image Library servlet components | |
| 5 * | |
| 6 * Copyright (C) 2003 Robert Casties (robcast@mail.berlios.de) | |
| 7 * | |
| 8 * This program is free software; you can redistribute it and/or modify it | |
| 9 * under the terms of the GNU General Public License as published by the Free | |
| 10 * Software Foundation; either version 2 of the License, or (at your option) | |
| 11 * any later version. | |
| 12 * | |
| 13 * Please read license.txt for the full details. A copy of the GPL may be found | |
| 14 * at http://www.gnu.org/copyleft/lgpl.html | |
| 15 * | |
| 16 * You should have received a copy of the GNU General Public License along with | |
| 17 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple | |
| 18 * Place, Suite 330, Boston, MA 02111-1307 USA | |
| 19 * | |
| 86 | 20 * Created on 03.03.2003 |
| 21 */ | |
| 22 | |
| 23 package digilib.io; | |
| 24 | |
| 25 import java.io.File; | |
| 91 | 26 import java.util.HashMap; |
| 159 | 27 import java.util.Iterator; |
| 28 import java.util.LinkedList; | |
| 29 import java.util.List; | |
| 270 | 30 import java.util.Map; |
| 86 | 31 |
| 181 | 32 import org.apache.log4j.Logger; |
| 33 | |
| 259 | 34 import digilib.servlet.DigilibConfiguration; |
| 35 | |
| 86 | 36 /** |
| 37 * @author casties | |
| 38 */ | |
| 91 | 39 public class DocuDirCache { |
| 86 | 40 |
| 181 | 41 /** general logger for this class */ |
| 270 | 42 Logger logger = Logger.getLogger(this.getClass()); |
| 282 | 43 |
| 159 | 44 /** HashMap of directories */ |
| 270 | 45 Map map = null; |
| 282 | 46 |
| 159 | 47 /** names of base directories */ |
| 270 | 48 String[] baseDirNames = null; |
| 282 | 49 |
| 159 | 50 /** array of allowed file classes (image/text) */ |
| 51 private int[] fileClasses = null; | |
| 282 | 52 |
| 159 | 53 /** number of files in the whole cache (approximate) */ |
| 270 | 54 long numFiles = 0; |
| 282 | 55 |
| 159 | 56 /** number of cache hits */ |
| 270 | 57 long hits = 0; |
| 282 | 58 |
| 159 | 59 /** number of cache misses */ |
| 270 | 60 long misses = 0; |
| 282 | 61 |
| 259 | 62 /** use safe (but slow) indexing */ |
| 63 boolean safeDirIndex = false; | |
| 282 | 64 |
| 270 | 65 /** the root directory element */ |
| 66 public static Directory ROOT = null; | |
| 86 | 67 |
| 176 | 68 /** |
| 69 * Constructor with array of base directory names and file classes. | |
| 70 * | |
| 71 * @param bd | |
| 72 * base directory names | |
| 159 | 73 */ |
| 282 | 74 public DocuDirCache(String[] bd, int[] fileClasses, |
| 75 DigilibConfiguration dlConfig) { | |
| 159 | 76 baseDirNames = bd; |
| 77 map = new HashMap(); | |
| 78 this.fileClasses = fileClasses; | |
| 259 | 79 safeDirIndex = dlConfig.getAsBoolean("safe-dir-index"); |
| 159 | 80 } |
| 282 | 81 |
| 176 | 82 /** |
| 83 * Constructor with array of base directory names. | |
| 84 * | |
| 85 * @param bd | |
| 86 * base directory names | |
| 86 | 87 */ |
| 88 public DocuDirCache(String[] bd) { | |
| 89 baseDirNames = bd; | |
| 91 | 90 map = new HashMap(); |
| 159 | 91 // default file class is CLASS_IMAGE |
| 92 fileClasses = new int[1]; | |
| 93 fileClasses[0] = FileOps.CLASS_IMAGE; | |
| 91 | 94 } |
| 95 | |
| 176 | 96 /** |
| 97 * The number of directories in the cache. | |
| 98 * | |
| 91 | 99 * @return |
| 100 */ | |
| 101 public int size() { | |
| 102 return (map != null) ? map.size() : 0; | |
| 86 | 103 } |
| 104 | |
| 176 | 105 /** |
| 106 * Add a DocuDirectory to the cache. | |
| 86 | 107 * |
| 108 * @param newdir | |
| 109 */ | |
| 110 public void put(DocuDirectory newdir) { | |
| 111 String s = newdir.getDirName(); | |
| 91 | 112 if (map.containsKey(s)) { |
| 197 | 113 logger.warn("Duplicate key in DocuDirCache.put -- ignoring!"); |
| 86 | 114 } else { |
| 91 | 115 map.put(s, newdir); |
| 86 | 116 numFiles += newdir.size(); |
| 117 } | |
| 118 } | |
| 119 | |
| 176 | 120 /** |
| 121 * Add a directory to the cache and check its parents. | |
| 151 | 122 * |
| 123 * @param newDir | |
| 124 */ | |
| 282 | 125 public synchronized void putDir(DocuDirectory newDir) { |
| 151 | 126 put(newDir); |
| 270 | 127 String parent = FileOps.parent(newDir.getDirName()); |
| 128 if (parent != "") { | |
| 151 | 129 // check the parent in the cache |
| 176 | 130 DocuDirectory pd = (DocuDirectory) map.get(parent); |
| 151 | 131 if (pd == null) { |
| 132 // the parent is unknown | |
| 133 pd = new DocuDirectory(parent, this); | |
| 134 putDir(pd); | |
| 135 } | |
| 136 newDir.setParent(pd); | |
| 137 } | |
| 138 } | |
| 139 | |
| 176 | 140 /** |
| 141 * Get a list with all children of a directory. | |
| 159 | 142 * |
| 282 | 143 * Returns a List of DocuDirectory's. Returns an empty List if the directory |
| 144 * has no children. If recurse is false then only direct children are | |
| 145 * returned. | |
| 159 | 146 * |
| 147 * @param dirname | |
| 176 | 148 * @param recurse |
| 149 * find all children and their children. | |
| 159 | 150 * @return |
| 151 */ | |
| 152 public List getChildren(String dirname, boolean recurse) { | |
| 153 List l = new LinkedList(); | |
| 176 | 154 for (Iterator i = map.keySet().iterator(); i.hasNext();) { |
| 209 | 155 String n = (String) i.next(); |
| 156 DocuDirectory dd = (DocuDirectory) map.get(n); | |
| 159 | 157 if (recurse) { |
| 158 if (dd.getDirName().startsWith(dirname)) { | |
| 159 l.add(dd); | |
| 160 } | |
| 161 } else { | |
| 270 | 162 if (FileOps.parent(dd.getDirName()).equals(dirname)) { |
| 159 | 163 l.add(dd); |
| 164 } | |
| 165 } | |
| 166 } | |
| 167 return l; | |
| 168 } | |
| 169 | |
| 176 | 170 /** |
| 282 | 171 * Returns the DocuDirent with the pathname <code>fn</code> and the index |
| 172 * <code>in</code> and the class <code>fc</code>. | |
| 91 | 173 * |
| 187 | 174 * If <code>fn</code> is a file then the corresponding DocuDirent is |
| 91 | 175 * returned and the index is ignored. |
| 176 * | |
| 176 | 177 * @param fn |
| 178 * digilib pathname | |
| 179 * @param in | |
| 180 * file index | |
| 246 | 181 * @param fc |
| 282 | 182 * file class |
| 176 | 183 * @return |
| 91 | 184 */ |
| 159 | 185 public DocuDirent getFile(String fn, int in, int fc) { |
| 86 | 186 DocuDirectory dd; |
| 187 // file number is 1-based, vector index is 0-based | |
| 188 int n = in - 1; | |
| 189 // first, assume fn is a directory and look in the cache | |
| 91 | 190 dd = (DocuDirectory) map.get(fn); |
| 191 if (dd == null) { | |
| 192 // cache miss | |
| 193 misses++; | |
| 176 | 194 /* |
| 195 * see if it's a directory | |
| 196 */ | |
| 152 | 197 File f = new File(baseDirNames[0], fn); |
| 91 | 198 if (f.isDirectory()) { |
| 151 | 199 dd = new DocuDirectory(fn, this); |
| 91 | 200 if (dd.isValid()) { |
| 201 // add to the cache | |
| 151 | 202 putDir(dd); |
| 91 | 203 } |
| 204 } else { | |
| 176 | 205 /* |
| 206 * maybe it's a file | |
| 207 */ | |
| 208 // get the parent directory string (like we store it in the | |
| 209 // cache) | |
| 246 | 210 String d = FileOps.parent(fn); |
| 176 | 211 // try it in the cache |
| 212 dd = (DocuDirectory) map.get(d); | |
| 213 if (dd == null) { | |
| 214 // try to read from disk | |
| 215 dd = new DocuDirectory(d, this); | |
| 216 if (dd.isValid()) { | |
| 217 // add to the cache | |
| 218 putDir(dd); | |
| 91 | 219 } else { |
| 176 | 220 // invalid path |
| 221 return null; | |
| 91 | 222 } |
|
99
226624784fe3
Small bug lead to null pointer exception when directory doesn't exist.
robcast
parents:
91
diff
changeset
|
223 } else { |
| 176 | 224 // it was not a real cache miss |
| 225 misses--; | |
| 91 | 226 } |
| 176 | 227 // get the file's index |
| 228 n = dd.indexOf(f.getName(), fc); | |
| 91 | 229 } |
| 230 } else { | |
| 231 // cache hit | |
| 232 hits++; | |
| 233 } | |
| 234 dd.refresh(); | |
| 235 if (dd.isValid()) { | |
| 236 try { | |
| 159 | 237 return dd.get(n, fc); |
| 187 | 238 } catch (IndexOutOfBoundsException e) { |
| 91 | 239 } |
| 240 } | |
| 241 return null; | |
| 242 } | |
| 243 | |
| 176 | 244 /** |
| 245 * Returns the DocuDirectory indicated by the pathname <code>fn</code>. | |
| 91 | 246 * |
| 247 * If <code>fn</code> is a file then its parent directory is returned. | |
| 248 * | |
| 176 | 249 * @param fn |
| 250 * digilib pathname | |
| 91 | 251 * @return |
| 252 */ | |
| 253 public DocuDirectory getDirectory(String fn) { | |
| 254 DocuDirectory dd; | |
| 255 // first, assume fn is a directory and look in the cache | |
| 256 dd = (DocuDirectory) map.get(fn); | |
| 86 | 257 if (dd == null) { |
| 258 // cache miss | |
| 259 misses++; | |
| 260 // see if it's a directory | |
| 152 | 261 File f = new File(baseDirNames[0], fn); |
| 86 | 262 if (f.isDirectory()) { |
| 151 | 263 dd = new DocuDirectory(fn, this); |
| 86 | 264 if (dd.isValid()) { |
| 265 // add to the cache | |
| 151 | 266 putDir(dd); |
| 86 | 267 } |
| 268 } else { | |
| 269 // maybe it's a file | |
| 270 if (f.canRead()) { | |
| 271 // try the parent directory in the cache | |
| 91 | 272 dd = (DocuDirectory) map.get(f.getParent()); |
| 86 | 273 if (dd == null) { |
| 274 // try to read from disk | |
| 151 | 275 dd = new DocuDirectory(f.getParent(), this); |
| 86 | 276 if (dd.isValid()) { |
| 277 // add to the cache | |
| 151 | 278 putDir(dd); |
| 86 | 279 } else { |
| 280 // invalid path | |
| 281 return null; | |
| 282 } | |
| 91 | 283 } else { |
| 284 // not a real cache miss then | |
| 285 misses--; | |
| 86 | 286 } |
|
99
226624784fe3
Small bug lead to null pointer exception when directory doesn't exist.
robcast
parents:
91
diff
changeset
|
287 } else { |
|
226624784fe3
Small bug lead to null pointer exception when directory doesn't exist.
robcast
parents:
91
diff
changeset
|
288 // it's not even a file :-( |
|
226624784fe3
Small bug lead to null pointer exception when directory doesn't exist.
robcast
parents:
91
diff
changeset
|
289 return null; |
| 86 | 290 } |
| 291 } | |
| 292 } else { | |
| 293 // cache hit | |
| 294 hits++; | |
| 295 } | |
| 296 dd.refresh(); | |
| 297 if (dd.isValid()) { | |
| 298 return dd; | |
| 299 } | |
| 300 return null; | |
| 301 } | |
| 302 | |
| 303 /** | |
| 304 * @return String[] | |
| 305 */ | |
| 306 public String[] getBaseDirNames() { | |
| 307 return baseDirNames; | |
| 308 } | |
| 309 | |
| 310 /** | |
| 311 * @return long | |
| 312 */ | |
| 313 public long getNumFiles() { | |
| 314 return numFiles; | |
| 315 } | |
| 316 | |
| 317 /** | |
| 318 * Sets the baseDirNames. | |
| 176 | 319 * |
| 320 * @param baseDirNames | |
| 321 * The baseDirNames to set | |
| 86 | 322 */ |
| 323 public void setBaseDirNames(String[] baseDirNames) { | |
| 324 this.baseDirNames = baseDirNames; | |
| 325 } | |
| 326 | |
| 327 /** | |
| 328 * @return long | |
| 329 */ | |
| 330 public long getHits() { | |
| 331 return hits; | |
| 332 } | |
| 333 | |
| 334 /** | |
| 335 * @return long | |
| 336 */ | |
| 337 public long getMisses() { | |
| 338 return misses; | |
| 339 } | |
| 340 | |
| 159 | 341 /** |
| 342 * @return | |
| 343 */ | |
| 344 public int[] getFileClasses() { | |
| 345 return fileClasses; | |
| 346 } | |
| 347 | |
| 348 /** | |
| 349 * @param fileClasses | |
| 350 */ | |
| 351 public void setFileClasses(int[] fileClasses) { | |
| 352 this.fileClasses = fileClasses; | |
| 353 } | |
| 176 | 354 |
| 86 | 355 } |