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
|
/*
* Copyright © 2010 Anthony Towns <aj@erisian.com.au>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
*/
package org.altusmetrum.altoslib_7;
import java.io.*;
import java.net.*;
public class AltosMapCache implements AltosMapCacheListener {
/* An entry in the MapCache */
class MapCacheElement implements AltosMapStoreListener {
AltosMapTile tile; /* Notify when image has been loaded */
AltosImage image;
AltosMapStore store;
long used;
class loader implements Runnable {
public void run() {
if (image != null)
tile.notify_image(image);
try {
image = map_interface.load_image(store.file);
} catch (Exception ex) {
}
if (image == null)
tile.set_status(AltosMapTile.failed);
else
tile.set_status(AltosMapTile.success);
tile.notify_image(image);
}
}
private void load() {
loader l = new loader();
Thread lt = new Thread(l);
lt.start();
}
public void flush() {
if (image != null) {
image.flush();
image = null;
}
}
public boolean has_map() {
return store.status() == AltosMapTile.success;
}
public synchronized void notify_store(AltosMapStore store, int status) {
switch (status) {
case AltosMapTile.loading:
break;
case AltosMapTile.success:
load();
break;
default:
tile.set_status(status);
tile.notify_image(null);
}
}
public MapCacheElement(AltosMapTile tile, AltosMapStore store) throws IOException {
this.tile = tile;
this.image = null;
this.store = store;
this.used = 0;
int status = store.status();
switch (status) {
case AltosMapTile.loading:
store.add_listener(this);
break;
case AltosMapTile.success:
load();
break;
default:
tile.set_status(status);
tile.notify_image(null);
break;
}
}
}
int min_cache_size; /* configured minimum cache size */
int cache_size; /* current cache size */
int requested_cache_size; /* cache size computed by application */
private Object fetch_lock = new Object();
private Object cache_lock = new Object();
AltosMapInterface map_interface;
MapCacheElement[] elements = new MapCacheElement[cache_size];
long used;
public void set_cache_size(int new_size) {
requested_cache_size = new_size;
if (new_size < min_cache_size)
new_size = min_cache_size;
if (new_size == cache_size)
return;
synchronized(cache_lock) {
MapCacheElement[] new_elements = new MapCacheElement[new_size];
for (int i = 0; i < cache_size; i++) {
if (i < new_size)
new_elements[i] = elements[i];
else if (elements[i] != null)
elements[i].flush();
}
elements = new_elements;
cache_size = new_size;
}
}
public AltosImage get(AltosMapTile tile, AltosMapStore store, int width, int height) {
int oldest = -1;
long age = used;
synchronized(cache_lock) {
MapCacheElement element = null;
for (int i = 0; i < cache_size; i++) {
element = elements[i];
if (element == null) {
oldest = i;
break;
}
if (store.equals(element.store)) {
element.used = used++;
return element.image;
}
if (element.used < age) {
oldest = i;
age = element.used;
}
}
try {
element = new MapCacheElement(tile, store);
element.used = used++;
if (elements[oldest] != null)
elements[oldest].flush();
elements[oldest] = element;
if (element.image == null)
tile.set_status(AltosMapTile.loading);
else
tile.set_status(AltosMapTile.success);
return element.image;
} catch (IOException e) {
tile.set_status(AltosMapTile.failed);
return null;
}
}
}
public void map_cache_changed(int map_cache) {
min_cache_size = map_cache;
set_cache_size(requested_cache_size);
}
public void dispose() {
AltosPreferences.unregister_map_cache_listener(this);
for (int i = 0; i < cache_size; i++) {
MapCacheElement element = elements[i];
if (element != null)
element.flush();
}
}
public AltosMapCache(AltosMapInterface map_interface) {
this.map_interface = map_interface;
min_cache_size = AltosPreferences.map_cache();
set_cache_size(0);
AltosPreferences.register_map_cache_listener(this);
}
}
|
