86
|
1 /* DocuDirCache.java
|
|
2
|
|
3 Digital Image Library servlet components
|
|
4
|
|
5 Copyright (C) 2003 Robert Casties (robcast@mail.berlios.de)
|
|
6
|
|
7 This program is free software; you can redistribute it and/or modify it
|
|
8 under the terms of the GNU General Public License as published by the
|
|
9 Free Software Foundation; either version 2 of the License, or (at your
|
|
10 option) any later version.
|
|
11
|
|
12 Please read license.txt for the full details. A copy of the GPL
|
|
13 may be found at http://www.gnu.org/copyleft/lgpl.html
|
|
14
|
|
15 You should have received a copy of the GNU General Public License
|
|
16 along with this program; if not, write to the Free Software
|
|
17 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
|
|
18
|
|
19 * Created on 03.03.2003
|
|
20 */
|
|
21
|
|
22 package digilib.io;
|
|
23
|
|
24 import java.io.File;
|
|
25 import java.util.Hashtable;
|
|
26
|
|
27 /**
|
|
28 * @author casties
|
|
29 */
|
|
30 public class DocuDirCache extends Hashtable {
|
|
31
|
|
32 // names of base directories
|
|
33 private String[] baseDirNames = null;
|
|
34 // number of files in the whole cache (not reliable)
|
|
35 private long numFiles = 0;
|
|
36 // number of cache hits
|
|
37 private long hits = 0;
|
|
38 // number of cache misses
|
|
39 private long misses = 0;
|
|
40
|
|
41 /*
|
|
42 * inherited constructors
|
|
43 */
|
|
44 public DocuDirCache(int initialCapacity, float loadFactor) {
|
|
45 super(initialCapacity, loadFactor);
|
|
46 }
|
|
47
|
|
48 public DocuDirCache(int initialCapacity) {
|
|
49 super(initialCapacity);
|
|
50 }
|
|
51
|
|
52 public DocuDirCache() {
|
|
53 super();
|
|
54 }
|
|
55
|
|
56 /*
|
|
57 * new and exiting stuff
|
|
58 */
|
|
59
|
|
60 /** Constructor with array of base directory names.
|
|
61 *
|
|
62 * @param bd base directory names
|
|
63 */
|
|
64 public DocuDirCache(String[] bd) {
|
|
65 super();
|
|
66 baseDirNames = bd;
|
|
67 }
|
|
68
|
|
69 /** Add a DocuDirectory to the cache.
|
|
70 *
|
|
71 * @param newdir
|
|
72 */
|
|
73 public void put(DocuDirectory newdir) {
|
|
74 String s = newdir.getDirName();
|
|
75 if (containsKey(s)) {
|
|
76 System.out.println("Baah, duplicate key in DocuDirectory.put!");
|
|
77 } else {
|
|
78 super.put(s, newdir);
|
|
79 numFiles += newdir.size();
|
|
80 }
|
|
81 }
|
|
82
|
|
83 public DocuFileset getFileset(String fn, int in) {
|
|
84 DocuDirectory dd;
|
|
85 // file number is 1-based, vector index is 0-based
|
|
86 int n = in - 1;
|
|
87 // first, assume fn is a directory and look in the cache
|
|
88 dd = (DocuDirectory) get(fn);
|
|
89 if (dd == null) {
|
|
90 // cache miss
|
|
91 misses++;
|
|
92 // see if it's a directory
|
|
93 File f = new File(baseDirNames[0] + fn);
|
|
94 if (f.isDirectory()) {
|
|
95 dd = new DocuDirectory(fn, baseDirNames);
|
|
96 if (dd.isValid()) {
|
|
97 // add to the cache
|
|
98 put(dd);
|
|
99 }
|
|
100 } else {
|
|
101 // maybe it's a file
|
|
102 if (f.canRead()) {
|
|
103 // try the parent directory in the cache
|
|
104 dd = (DocuDirectory) get(f.getParent());
|
|
105 if (dd == null) {
|
|
106 // try to read from disk
|
|
107 dd = new DocuDirectory(f.getParent(), baseDirNames);
|
|
108 if (dd.isValid()) {
|
|
109 // add to the cache
|
|
110 put(dd);
|
|
111 } else {
|
|
112 // invalid path
|
|
113 return null;
|
|
114 }
|
|
115 }
|
|
116 // get the file's index
|
|
117 n = dd.indexOf(f.getName());
|
|
118 }
|
|
119 }
|
|
120 } else {
|
|
121 // cache hit
|
|
122 hits++;
|
|
123 }
|
|
124 dd.refresh();
|
|
125 if (dd.isValid()) {
|
|
126 try {
|
|
127 return (DocuFileset) dd.elementAt(n);
|
|
128 } catch (ArrayIndexOutOfBoundsException e) {
|
|
129 }
|
|
130 }
|
|
131 return null;
|
|
132 }
|
|
133
|
|
134 public DocuDirectory getDirectory(String fn) {
|
|
135 DocuDirectory dd;
|
|
136 // first, assume fn is a directory and look in the cache
|
|
137 dd = (DocuDirectory) get(fn);
|
|
138 if (dd == null) {
|
|
139 // cache miss
|
|
140 misses++;
|
|
141 // see if it's a directory
|
|
142 File f = new File(baseDirNames[0] + fn);
|
|
143 if (f.isDirectory()) {
|
|
144 dd = new DocuDirectory(fn, baseDirNames);
|
|
145 if (dd.isValid()) {
|
|
146 // add to the cache
|
|
147 put(dd);
|
|
148 }
|
|
149 } else {
|
|
150 // maybe it's a file
|
|
151 if (f.canRead()) {
|
|
152 // try the parent directory in the cache
|
|
153 dd = (DocuDirectory) get(f.getParent());
|
|
154 if (dd == null) {
|
|
155 // try to read from disk
|
|
156 dd = new DocuDirectory(f.getParent(), baseDirNames);
|
|
157 if (dd.isValid()) {
|
|
158 // add to the cache
|
|
159 put(dd);
|
|
160 } else {
|
|
161 // invalid path
|
|
162 return null;
|
|
163 }
|
|
164 }
|
|
165 }
|
|
166 }
|
|
167 } else {
|
|
168 // cache hit
|
|
169 hits++;
|
|
170 }
|
|
171 dd.refresh();
|
|
172 if (dd.isValid()) {
|
|
173 return dd;
|
|
174 }
|
|
175 return null;
|
|
176 }
|
|
177
|
|
178 /**
|
|
179 * @return String[]
|
|
180 */
|
|
181 public String[] getBaseDirNames() {
|
|
182 return baseDirNames;
|
|
183 }
|
|
184
|
|
185 /**
|
|
186 * @return long
|
|
187 */
|
|
188 public long getNumFiles() {
|
|
189 return numFiles;
|
|
190 }
|
|
191
|
|
192 /**
|
|
193 * Sets the baseDirNames.
|
|
194 * @param baseDirNames The baseDirNames to set
|
|
195 */
|
|
196 public void setBaseDirNames(String[] baseDirNames) {
|
|
197 this.baseDirNames = baseDirNames;
|
|
198 }
|
|
199
|
|
200 /**
|
|
201 * @return long
|
|
202 */
|
|
203 public long getHits() {
|
|
204 return hits;
|
|
205 }
|
|
206
|
|
207 /**
|
|
208 * @return long
|
|
209 */
|
|
210 public long getMisses() {
|
|
211 return misses;
|
|
212 }
|
|
213
|
|
214 }
|