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
/*
* $Revision$
* $Date$
*
* Copyright (C) 1999-2006 Jive Software. All rights reserved.
*
* Use is subject to license terms.
*/
package org.jivesoftware.util;
import java.util.Collection;
import java.util.HashMap;
import java.util.Map;
/**
* Centralized management of caches. Caches are essential for performance and scalability.
*
* @see Cache
* @author Matt Tucker
*/
public class CacheManager {
private static Map<String, Cache> caches = new HashMap<String, Cache>();
private static final long DEFAULT_EXPIRATION_TIME = JiveConstants.HOUR * 6;
/**
* Initializes a cache given it's name and max size. The default expiration time
* of six hours will be used. If a cache with the same name has already been initialized,
* this method returns the existing cache.<p>
*
* The size and expiration time for the cache can be overridden by setting Jive properties
* in the format:<ul>
*
* <li>Size: "cache.CACHE_NAME.size", in bytes.
* <li>Expiration: "cache.CACHE_NAME.expirationTime", in milleseconds.
* </ul>
* where CACHE_NAME is the name of the cache.
*
* @param name the name of the cache to initialize.
* @param propertiesName the properties file name prefix where settings for the cache
* are stored. The name is will be prefixed by "cache." before it is
* looked up.
* @param size the size the cache can grow to, in bytes.
*/
public static Cache initializeCache(String name, String propertiesName, int size) {
return initializeCache(name, propertiesName, size, DEFAULT_EXPIRATION_TIME);
}
/**
* Initializes a cache given it's name, max size, and expiration time. If a cache with
* the same name has already been initialized, this method returns the existing cache.<p>
*
* The size and expiration time for the cache can be overridden by setting Jive properties
* in the format:<ul>
*
* <li>Size: "cache.CACHE_NAME.size", in bytes.
* <li>Expiration: "cache.CACHE_NAME.expirationTime", in milleseconds.
* </ul>
* where CACHE_NAME is the name of the cache.
*
* @param name the name of the cache to initialize.
* @param propertiesName the properties file name prefix where settings for the cache are
* stored. The name is will be prefixed by "cache." before it is
* looked up.
* @param size the size the cache can grow to, in bytes.
* @param expirationTime the default max lifetime of the cache, in milliseconds.
*/
public static Cache initializeCache(String name, String propertiesName, int size,
long expirationTime) {
Cache cache = caches.get(name);
if (cache == null) {
size = JiveGlobals.getIntProperty("cache." + name + ".size", size);
expirationTime = (long) JiveGlobals.getIntProperty(
"cache." + propertiesName + ".expirationTime", (int) expirationTime);
caches.put(name, new Cache(name, size, expirationTime));
}
return cache;
}
/**
* Returns the cache specified by name. The cache must be initialized before this
* method can be called.
*
* @param name the name of the cache to return.
* @return the cache found, or <tt>null</tt> if no cache by that name
* has been initialized.
*/
public static Cache getCache(String name) {
return caches.get(name);
}
/**
* Returns the list of caches being managed by this manager.
*
* @return the list of caches being managed by this manager.
*/
public static Collection<Cache> getCaches() {
return caches.values();
}
}