blob: 508a87e4bba4c22d8c8d120f935d4b41581d0194 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
|
/*
* Copyright 2003-2004 Apache Software Foundation
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*/
package org.apache.tools.ant.types.selectors.modifiedselector;
import java.util.Iterator;
import java.util.Vector;
import java.util.Enumeration;
import java.util.Properties;
import java.io.File;
import java.io.BufferedInputStream;
import java.io.FileInputStream;
import java.io.BufferedOutputStream;
import java.io.FileOutputStream;
/**
* Use java.util.Properties for storing the values.
* The use of this Cache-implementation requires the use of the parameter
* <param name="cache.cachefile" .../> for defining, where to store the
* properties file.
*
* The ModifiedSelector sets the <i>cachefile</i> to the default value
* <i>cache.properties</i>.
*
* Supported <param>s are:
* <table>
* <tr>
* <th>name</th><th>values</th><th>description</th><th>required</th>
* </tr>
* <tr>
* <td> cache.cachefile </td>
* <td> <i>path to file</i> </td>
* <td> the name of the properties file </td>
* <td> yes </td>
* </tr>
* </table>
*
* @author Jan Mat\u00e8rne
* @version 2003-09-13
* @since Ant 1.6
*/
public class PropertiesfileCache implements Cache {
// ----- member variables - configuration -----
/** Where to store the properties? */
private File cachefile = null;
/** Object for storing the key-value-pairs. */
private Properties cache = new Properties();
// ----- member variables - internal use -----
/** Is the cache already loaded? Prevents from multiple load operations. */
private boolean cacheLoaded = false;
/** Must the cache be saved? Prevents from multiple save operations. */
private boolean cacheDirty = true;
// ----- Constructors -----
/** Bean-Constructor. */
public PropertiesfileCache() {
}
/**
* Constructor.
* @param cachefile set the cachefile
*/
public PropertiesfileCache(File cachefile) {
this.cachefile = cachefile;
}
// ----- Cache-Configuration -----
public void setCachefile(File file) {
cachefile = file;
}
public File getCachefile() { return cachefile; }
public boolean isValid() {
return (cachefile != null);
}
// ----- Data Access
public void load() {
if ((cachefile != null) && cachefile.isFile() && cachefile.canRead()) {
try {
BufferedInputStream bis = new BufferedInputStream(
new FileInputStream(cachefile));
cache.load(bis);
bis.close();
} catch (Exception e) {
e.printStackTrace();
}
}
// after loading the cache is up to date with the file
cacheLoaded = true;
cacheDirty = false;
}
/**
* Saves modification of the cache.
* Cache is only saved if there is one ore more entries.
* Because entries can not be deleted by this API, this Cache
* implementation checks the existence of entries before creating the file
* for performance optimisation.
*/
public void save() {
if (!cacheDirty) {
return;
}
if ((cachefile != null) && cache.propertyNames().hasMoreElements()) {
try {
BufferedOutputStream bos = new BufferedOutputStream(
new FileOutputStream(cachefile));
cache.store(bos, null);
bos.flush();
bos.close();
} catch (Exception e) {
e.printStackTrace();
}
}
cacheDirty = false;
}
/** Deletes the cache and its underlying file. */
public void delete() {
cache = new Properties();
cachefile.delete();
cacheLoaded = true;
cacheDirty = false;
}
/**
* Returns a value for a given key from the cache.
* @param key the key
* @return the stored value
*/
public Object get(Object key) {
if (!cacheLoaded) {
load();
}
try {
return cache.getProperty(String.valueOf(key));
} catch (ClassCastException e) {
return null;
}
}
/**
* Saves a key-value-pair in the cache.
* @param key the key
* @param value the value
*/
public void put(Object key, Object value) {
cache.put(String.valueOf(key), String.valueOf(value));
cacheDirty = true;
}
/**
* Returns an iterator over the keys in the cache.
* @return An iterator over the keys.
*/
public Iterator iterator() {
Vector v = new java.util.Vector();
Enumeration en = cache.propertyNames();
while (en.hasMoreElements()) {
v.add(en.nextElement());
}
return v.iterator();
}
// ----- additional -----
/**
* Override Object.toString().
* @return information about this cache
*/
public String toString() {
StringBuffer buf = new StringBuffer();
buf.append("<PropertiesfileCache:");
buf.append("cachefile=").append(cachefile);
buf.append(";noOfEntries=").append(cache.size());
buf.append(">");
return buf.toString();
}
}
|