ehcache.xml说明:
操作类实例
转自: http://blog.csdn.net/longronglin/article/details/6699641
01.
<?
xml version="1.0" encoding="UTF-8"
?>
02.
03. <!-- CacheManager Configuration ========================== An ehcache.xml
04. corresponds to a single CacheManager. See instructions below or the ehcache
05. schema (ehcache.xsd) on how to configure. System property tokens can be specified
06. in this file which are replaced when the configuration is loaded. For example
07. multicastGroupPort=${multicastGroupPort} can be replaced with the System
08. property either from an environment variable or a system property specified
09. with a command line switch such as -DmulticastGroupPort=4446. The attributes
10. of <ehcache> are: * name - an optional name for the CacheManager. The name
11. is optional and primarily used for documentation or to distinguish Terracotta
12. clustered cache state. With Terracotta clustered caches, a combination of
13. CacheManager name and cache name uniquely identify a particular cache store
14. in the Terracotta clustered memory. * updateCheck - an optional boolean flag
15. specifying whether this CacheManager should check for new versions of Ehcache
16. over the Internet. If not specified, updateCheck="true". * monitoring - an
17. optional setting that determines whether the CacheManager should automatically
18. register the SampledCacheMBean with the system MBean server. Currently, this
19. monitoring is only useful when using Terracotta clustering and using the
20. Terracotta Developer Console. With the "autodetect" value, the presence of
21. Terracotta clustering will be detected and monitoring, via the Developer
22. Console, will be enabled. Other allowed values are "on" and "off". The default
23. is "autodetect". This setting does not perform any function when used with
24. JMX monitors. * dynamicConfig - an optional setting that can be used to disable
25. dynamic configuration of caches associated with this CacheManager. By default
26. this is set to true - i.e. dynamic configuration is enabled. Dynamically
27. configurable caches can have their TTI, TTL and maximum disk and in-memory
28. capacity changed at runtime through the cache's configuration object. -->
29. < ehcache xmlns:xsi ="http://www.w3.org/2001/XMLSchema-instance"
30. xsi:noNamespaceSchemaLocation ="ehcache.xsd" updateCheck ="true"
31. monitoring ="autodetect" dynamicConfig ="true" >
32.
33. <!-- DiskStore configuration ======================= The diskStore element
34. is optional. To turn off disk store path creation, comment out the diskStore
35. element below. Configure it if you have overflowToDisk or diskPersistent
36. enabled for any cache. If it is not configured, and a cache is created which
37. requires a disk store, a warning will be issued and java.io.tmpdir will automatically
38. be used. diskStore has only one attribute - "path". It is the path to the
39. directory where .data and .index files will be created. If the path is one
40. of the following Java System Property it is replaced by its value in the
41. running VM. For backward compatibility these should be specified without
42. being enclosed in the ${token} replacement syntax. The following properties
43. are translated: * user.home - User's home directory * user.dir - User's current
44. working directory * java.io.tmpdir - Default temp file path * ehcache.disk.store.dir
45. - A system property you would normally specify on the command line e.g. java
46. -Dehcache.disk.store.dir=/u01/myapp/diskdir Subdirectories can be specified
47. below the property e.g. java.io.tmpdir/one -->
48. < diskStore path ="java.io.tmpdir" />
49.
50.
51. <!-- TransactionManagerLookup configuration ======================================
52. This class is used by ehcache to lookup the JTA TransactionManager use in
53. the application using an XA enabled ehcache. If no class is specified then
54. DefaultTransactionManagerLookup will find the TransactionManager in the following
55. order *GenericJNDI (i.e. jboss, where the property jndiName controls the
56. name of the TransactionManager object to look up) *Websphere *Bitronix *Atomikos
57. You can provide you own lookup class that implements the net.sf.ehcache.transaction.manager.TransactionManagerLookup
58. interface. -->
59.
60. < transactionManagerLookup
61. class ="net.sf.ehcache.transaction.manager.DefaultTransactionManagerLookup"
62. properties ="" propertySeparator =":" />
63.
64. <!-- CacheManagerEventListener ========================= Specifies a CacheManagerEventListenerFactory
65. which is notified when Caches are added or removed from the CacheManager.
66. The attributes of CacheManagerEventListenerFactory are: * class - a fully
67. qualified factory class name * properties - comma separated properties having
68. meaning only to the factory. Sets the fully qualified class name to be registered
69. as the CacheManager event listener. The events include: * adding a Cache
70. * removing a Cache Callbacks to listener methods are synchronous and unsynchronized.
71. It is the responsibility of the implementer to safely handle the potential
72. performance and thread safety issues depending on what their listener is
73. doing. If no class is specified, no listener is created. There is no default. -->
74.
75. < cacheManagerEventListenerFactory
76. class ="" properties ="" />
77.
78. <!-- TerracottaConfig ======================== (Enable for Terracotta clustered
79. operation) Note: You need to install and run one or more Terracotta servers
80. to use Terracotta clustering. See http://www.terracotta.org/web/display/orgsite/Download.
81. Specifies a TerracottaConfig which will be used to configure the Terracotta
82. runtime for this CacheManager. Configuration can be specified in two main
83. ways: by reference to a source of configuration or by use of an embedded
84. Terracotta configuration file. To specify a reference to a source (or sources)
85. of configuration, use the url attribute. The url attribute must contain a
86. comma-separated list of: * path to Terracotta configuration file (usually
87. named tc-config.xml) * URL to Terracotta configuration file * <server host>:<port>
88. of running Terracotta Server instance Simplest example for pointing to a
89. Terracotta server on this machine: <terracottaConfig url="localhost:9510"/>
90. Example using a path to Terracotta configuration file: <terracottaConfig
91. url="/app/config/tc-config.xml"/> Example using a URL to a Terracotta configuration
92. file: <terracottaConfig url="http://internal/ehcache/app/tc-config.xml"/>
93. Example using multiple Terracotta server instance URLs (for fault tolerance):
94. <terracottaConfig url="host1:9510,host2:9510,host3:9510"/> To embed a Terracotta
95. configuration file within the ehcache configuration, simply place a normal
96. Terracotta XML config within the <terracottaConfig> element. Example: <terracottaConfig>
97. <tc-config> <servers> <server host="server1" name="s1"/> <server host="server2"
98. name="s2"/> </servers> <clients> <logs>app/logs-%i</logs> </clients> </tc-config>
99. </terracottaConfig> For more information on the Terracotta configuration,
100. see the Terracotta documentation. -->
101.
102.
103. <!-- Cache configuration =================== The following attributes are
104. required. name: Sets the name of the cache. This is used to identify the
105. cache. It must be unique. maxElementsInMemory: Sets the maximum number of
106. objects that will be created in memory maxElementsOnDisk: Sets the maximum
107. number of objects that will be maintained in the DiskStore The default value
108. is zero, meaning unlimited. eternal: Sets whether elements are eternal. If
109. eternal, timeouts are ignored and the element is never expired. overflowToDisk:
110. Sets whether elements can overflow to disk when the memory store has reached
111. the maxInMemory limit. The following attributes and elements are optional.
112. overflowToOffHeap: (boolean) This feature is available only in enterprise
113. versions of Ehcache. When set to true, enables the cache to utilize "off-heap"
114. memory storage to improve performance. Off-heap memory is not subject to
115. Java GC cycles and has a size limit set by the Java property MaxDirectMemorySize.
116. The default value is false. maxMemoryOffHeap: (string) This feature is available
117. only in enterprise versions of Ehcache. Sets the amount of off-heap memory
118. available to the cache. This attribute's values are given as <number>k|K|m|M|g|G|t|T
119. for kilobytes (k|K), megabytes (m|M), gigabytes (g|G), or terrabytes (t|T).
120. For example, maxMemoryOffHeap="2g" allots 2 gigabytes to off-heap memory.
121. In effect only if overflowToOffHeap is true. timeToIdleSeconds: Sets the
122. time to idle for an element before it expires. i.e. The maximum amount of
123. time between accesses before an element expires Is only used if the element
124. is not eternal. Optional attribute. A value of 0 means that an Element can
125. idle for infinity. The default value is 0. timeToLiveSeconds: Sets the time
126. to live for an element before it expires. i.e. The maximum time between creation
127. time and when an element expires. Is only used if the element is not eternal.
128. Optional attribute. A value of 0 means that and Element can live for infinity.
129. The default value is 0. diskPersistent: Whether the disk store persists between
130. restarts of the Virtual Machine. The default value is false. diskExpiryThreadIntervalSeconds:
131. The number of seconds between runs of the disk expiry thread. The default
132. value is 120 seconds. diskSpoolBufferSizeMB: This is the size to allocate
133. the DiskStore for a spool buffer. Writes are made to this area and then asynchronously
134. written to disk. The default size is 30MB. Each spool buffer is used only
135. by its cache. If you get OutOfMemory errors consider lowering this value.
136. To improve DiskStore performance consider increasing it. Trace level logging
137. in the DiskStore will show if put back ups are occurring. clearOnFlush: whether
138. the MemoryStore should be cleared when flush() is called on the cache. By
139. default, this is true i.e. the MemoryStore is cleared. memoryStoreEvictionPolicy:
140. Policy would be enforced upon reaching the maxElementsInMemory limit. Default
141. policy is Least Recently Used (specified as LRU). Other policies available
142. - First In First Out (specified as FIFO) and Less Frequently Used (specified
143. as LFU) Cache elements can also contain sub elements which take the same
144. format of a factory class and properties. Defined sub-elements are: * cacheEventListenerFactory
145. - Enables registration of listeners for cache events, such as put, remove,
146. update, and expire. * bootstrapCacheLoaderFactory - Specifies a BootstrapCacheLoader,
147. which is called by a cache on initialisation to prepopulate itself. * cacheExtensionFactory
148. - Specifies a CacheExtension, a generic mechansim to tie a class which holds
149. a reference to a cache to the cache lifecycle. * cacheExceptionHandlerFactory
150. - Specifies a CacheExceptionHandler, which is called when cache exceptions
151. occur. * cacheLoaderFactory - Specifies a CacheLoader, which can be used
152. both asynchronously and synchronously to load objects into a cache. More
153. than one cacheLoaderFactory element can be added, in which case the loaders
154. form a chain which are executed in order. If a loader returns null, the next
155. in chain is called. Cache Event Listeners All cacheEventListenerFactory elements
156. can take an optional property listenFor that describes which events will
157. be delivered in a clustered environment. The listenFor attribute has the
158. following allowed values: * all - the default is to deliver all local and
159. remote events * local - deliver only events originating in the current node
160. * remote - deliver only events originating in other nodes Example of setting
161. up a logging listener for local cache events: <cacheEventListenerFactory
162. class="my.company.log.CacheLogger" listenFor="local" /> Cache Exception Handling
163. ++++++++++++++++++++++++ By default, most cache operations will propagate
164. a runtime CacheException on failure. An interceptor, using a dynamic proxy,
165. may be configured so that a CacheExceptionHandler can be configured to intercept
166. Exceptions. Errors are not intercepted. It is configured as per the following
167. example: <cacheExceptionHandlerFactory class="com.example.ExampleExceptionHandlerFactory"
168. properties="logLevel=FINE"/> Caches with ExceptionHandling configured are
169. not of type Cache, but are of type Ehcache only, and are not available using
170. CacheManager.getCache(), but using CacheManager.getEhcache(). Cache Loader
171. ++++++++++++ A default CacheLoader may be set which loads objects into the
172. cache through asynchronous and synchronous methods on Cache. This is different
173. to the bootstrap cache loader, which is used only in distributed caching.
174. It is configured as per the following example: <cacheLoaderFactory class="com.example.ExampleCacheLoaderFactory"
175. properties="type=int,startCounter=10"/> XA Cache ++++++++ To enable an ehcache
176. as a participant in the JTA Transaction, just have the following attribute
177. transactionalMode="xa", otherwise the default is transactionalMode="off"
178. Cache Writer ++++++++++++ A CacheWriter maybe be set to write to an underlying
179. resource. Only one CacheWriter can be been to a cache. It is configured as
180. per the following example for write-through: <cacheWriter writeMode="write-through"
181. notifyListenersOnException="true"> <cacheWriterFactory class="net.sf.ehcache.writer.TestCacheWriterFactory"
182. properties="type=int,startCounter=10"/> </cacheWriter> And it is configured
183. as per the following example for write-behind: <cacheWriter writeMode="write-behind"
184. minWriteDelay="1" maxWriteDelay="5" rateLimitPerSecond="5" writeCoalescing="true"
185. writeBatching="true" writeBatchSize="1" retryAttempts="2" retryAttemptDelaySeconds="1">
186. <cacheWriterFactory class="net.sf.ehcache.writer.TestCacheWriterFactory"
187. properties="type=int,startCounter=10"/> </cacheWriter> The cacheWriter element
188. has the following attributes: * writeMode: the write mode, write-through
189. or write-behind These attributes only apply to write-through mode: * notifyListenersOnException:
190. Sets whether to notify listeners when an exception occurs on a writer operation.
191. These attributes only apply to write-behind mode: * minWriteDelay: Set the
192. minimum number of seconds to wait before writing behind. If set to a value
193. greater than 0, it permits operations to build up in the queue. This is different
194. from the maximum write delay in that by waiting a minimum amount of time,
195. work is always being built up. If the minimum write delay is set to zero
196. and the CacheWriter performs its work very quickly, the overhead of processing
197. the write behind queue items becomes very noticeable in a cluster since all
198. the operations might be done for individual items instead of for a collection
199. of them. * maxWriteDelay: Set the maximum number of seconds to wait before
200. writing behind. If set to a value greater than 0, it permits operations to
201. build up in the queue to enable effective coalescing and batching optimisations.
202. * writeBatching: Sets whether to batch write operations. If set to true,
203. writeAll and deleteAll will be called on the CacheWriter rather than write
204. and delete being called for each key. Resources such as databases can perform
205. more efficiently if updates are batched, thus reducing load. * writeBatchSize:
206. Sets the number of operations to include in each batch when writeBatching
207. is enabled. If there are less entries in the write-behind queue than the
208. batch size, the queue length size is used. * rateLimitPerSecond: Sets the
209. maximum number of write operations to allow per second when writeBatching
210. is enabled. * writeCoalescing: Sets whether to use write coalescing. If set
211. to true and multiple operations on the same key are present in the write-behind
212. queue, only the latest write is done, as the others are redundant. * retryAttempts:
213. Sets the number of times the operation is retried in the CacheWriter, this
214. happens after the original operation. * retryAttemptDelaySeconds: Sets the
215. number of seconds to wait before retrying an failed operation. Cache Extension
216. +++++++++++++++ CacheExtensions are a general purpose mechanism to allow
217. generic extensions to a Cache. CacheExtensions are tied into the Cache lifecycle.
218. CacheExtensions are created using the CacheExtensionFactory which has a <code>createCacheCacheExtension()</code>
219. method which takes as a parameter a Cache and properties. It can thus call
220. back into any public method on Cache, including, of course, the load methods.
221. Extensions are added as per the following example: <cacheExtensionFactory
222. class="com.example.FileWatchingCacheRefresherExtensionFactory" properties="refreshIntervalMillis=18000,
223. loaderTimeout=3000, flushPeriod=whatever, someOtherProperty=someValue "/>
224. Terracotta Clustering +++++++++++++++++++++ Cache elements can also contain
225. information about whether the cache can be clustered with Terracotta. The
226. <terracotta> sub-element has the following attributes: * clustered=true|false
227. - indicates whether this cache should be clustered with Terracotta. By default,
228. if the <terracotta> element is included, clustered=true. * valueMode=serialization|identity
229. - indicates whether this cache should be clustered with serialized copies
230. of the values or using Terracotta identity mode. By default, values will
231. be cached in serialization mode which is similar to other replicated Ehcache
232. modes. The identity mode is only available in certain Terracotta deployment
233. scenarios and will maintain actual object identity of the keys and values
234. across the cluster. In this case, all users of a value retrieved from the
235. cache are using the same clustered value and must provide appropriate locking
236. for any changes made to the value (or objects referred to by the value).
237. * synchronousWrites=true|false - When set to true, clustered caches use Terracotta
238. SYNCHRONOUS WRITE locks. Asynchronous writes (synchronousWrites="false")
239. maximize performance by allowing clients to proceed without waiting for a
240. "transaction received" acknowledgement from the server. Synchronous writes
241. (synchronousWrites="true") maximize data safety by requiring that a client
242. receive server acknowledgement of a transaction before that client can proceed.
243. If coherence mode is disabled using configuration (coherent="false") or through
244. the coherence API, only asynchronous writes can occur (synchronousWrites="true"
245. is ignored). By default this value is false (i.e. clustered caches use normal
246. Terracotta WRITE locks). * coherent=true|false - indicates whether this cache
247. should have coherent reads and writes with guaranteed consistency across
248. the cluster. By default, its value is true. If this attribute is set to false
249. (or "incoherent" mode), values from the cache are read without locking, possibly
250. yielding stale data. Writes to a cache in incoherent mode are batched and
251. applied without acquiring cluster-wide locks, possibly creating inconsistent
252. values across cluster. Incoherent mode is a performance optimization with
253. weaker concurrency guarantees and should generally be used for bulk-loading
254. caches, for loading a read-only cache, or where the application that can
255. tolerate reading stale data. This setting overrides coherentReads, which
256. is deprecated. * copyOnRead=true|false - indicates whether cache values are
257. deserialized on every read or if the materialized cache value can be re-used
258. between get() calls. This setting is useful if a cache is being shared by
259. callers with disparate classloaders or to prevent local drift if keys/values
260. are mutated locally w/o putting back to the cache. NOTE: This setting is
261. only relevant for caches with valueMode=serialization Simplest example to
262. indicate clustering: <terracotta/> To indicate the cache should not be clustered
263. (or remove the <terracotta> element altogether): <terracotta clustered="false"/>
264. To indicate the cache should be clustered using identity mode: <terracotta
265. clustered="true" valueMode="identity"/> To indicate the cache should be clustered
266. using incoherent mode for bulk load: <terracotta clustered="true" coherent="false"/>
267. To indicate the cache should be clustered using synchronous-write locking
268. level: <terracotta clustered="true" synchronousWrites="true"/> -->
269.
270. <!-- Mandatory Default Cache configuration. These settings will be applied
271. to caches created programmtically using CacheManager.add(String cacheName).
272. The defaultCache has an implicit name "default" which is a reserved cache
273. name. -->
274. < defaultCache maxElementsInMemory ="0" eternal ="false"
275. overflowToDisk ="true" timeToIdleSeconds ="1200" timeToLiveSeconds ="1200" >
276.
277. </ defaultCache >
278.
279. <!-- Sample caches. Following are some example caches. Remove these before
280. use. -->
281.
282. <!-- Sample cache named sampleCache1 This cache contains a maximum in memory
283. of 10000 elements, and will expire an element if it is idle for more than
284. 5 minutes and lives for more than 10 minutes. If there are more than 10000
285. elements it will overflow to the disk cache, which in this configuration
286. will go to wherever java.io.tmp is defined on your system. On a standard
287. Linux system this will be /tmp" -->
288. < cache name ="sampleCache1" maxElementsInMemory ="10000"
289. maxElementsOnDisk ="1000" eternal ="false" overflowToDisk ="true"
290. diskSpoolBufferSizeMB ="20" timeToIdleSeconds ="300" timeToLiveSeconds ="600"
291. memoryStoreEvictionPolicy ="LFU" />
292.
293.
294. <!-- Sample cache named sampleCache2 This cache has a maximum of 1000 elements
295. in memory. There is no overflow to disk, so 1000 is also the maximum cache
296. size. Note that when a cache is eternal, timeToLive and timeToIdle are not
297. used and do not need to be specified. -->
298. < cache name ="sampleCache2" maxElementsInMemory ="1000" eternal ="true"
299. overflowToDisk ="false" memoryStoreEvictionPolicy ="FIFO" />
300.
301.
302. <!-- Sample cache named sampleCache3. This cache overflows to disk. The
303. disk store is persistent between cache and VM restarts. The disk expiry thread
304. interval is set to 10 minutes, overriding the default of 2 minutes. -->
305. < cache name ="sampleCache3" maxElementsInMemory ="500" eternal ="false"
306. overflowToDisk ="true" timeToIdleSeconds ="300" timeToLiveSeconds ="600"
307. diskPersistent ="true" diskExpiryThreadIntervalSeconds ="1"
308. memoryStoreEvictionPolicy ="LFU" />
309.
310. <!-- Sample Terracotta clustered cache named sampleTerracottaCache. This
311. cache uses Terracotta to cluster the contents of the cache. -->
312. < cache name ="sampleTerracottaCache" maxElementsInMemory ="1000"
313. eternal ="false" timeToIdleSeconds ="3600" timeToLiveSeconds ="1800"
314. overflowToDisk ="false" >
315.
316.
317. </ cache >
318.
319. <!-- Sample xa enabled cache name xaCache -->
320.
321. < cache name ="xaCache" maxElementsInMemory ="500" eternal ="false"
322. timeToIdleSeconds ="300" timeToLiveSeconds ="600" overflowToDisk ="false"
323. diskPersistent ="false" diskExpiryThreadIntervalSeconds ="1" >
324.
325. </ cache >
326.
327.
328. </ ehcache >
02.
03. <!-- CacheManager Configuration ========================== An ehcache.xml
04. corresponds to a single CacheManager. See instructions below or the ehcache
05. schema (ehcache.xsd) on how to configure. System property tokens can be specified
06. in this file which are replaced when the configuration is loaded. For example
07. multicastGroupPort=${multicastGroupPort} can be replaced with the System
08. property either from an environment variable or a system property specified
09. with a command line switch such as -DmulticastGroupPort=4446. The attributes
10. of <ehcache> are: * name - an optional name for the CacheManager. The name
11. is optional and primarily used for documentation or to distinguish Terracotta
12. clustered cache state. With Terracotta clustered caches, a combination of
13. CacheManager name and cache name uniquely identify a particular cache store
14. in the Terracotta clustered memory. * updateCheck - an optional boolean flag
15. specifying whether this CacheManager should check for new versions of Ehcache
16. over the Internet. If not specified, updateCheck="true". * monitoring - an
17. optional setting that determines whether the CacheManager should automatically
18. register the SampledCacheMBean with the system MBean server. Currently, this
19. monitoring is only useful when using Terracotta clustering and using the
20. Terracotta Developer Console. With the "autodetect" value, the presence of
21. Terracotta clustering will be detected and monitoring, via the Developer
22. Console, will be enabled. Other allowed values are "on" and "off". The default
23. is "autodetect". This setting does not perform any function when used with
24. JMX monitors. * dynamicConfig - an optional setting that can be used to disable
25. dynamic configuration of caches associated with this CacheManager. By default
26. this is set to true - i.e. dynamic configuration is enabled. Dynamically
27. configurable caches can have their TTI, TTL and maximum disk and in-memory
28. capacity changed at runtime through the cache's configuration object. -->
29. < ehcache xmlns:xsi ="http://www.w3.org/2001/XMLSchema-instance"
30. xsi:noNamespaceSchemaLocation ="ehcache.xsd" updateCheck ="true"
31. monitoring ="autodetect" dynamicConfig ="true" >
32.
33. <!-- DiskStore configuration ======================= The diskStore element
34. is optional. To turn off disk store path creation, comment out the diskStore
35. element below. Configure it if you have overflowToDisk or diskPersistent
36. enabled for any cache. If it is not configured, and a cache is created which
37. requires a disk store, a warning will be issued and java.io.tmpdir will automatically
38. be used. diskStore has only one attribute - "path". It is the path to the
39. directory where .data and .index files will be created. If the path is one
40. of the following Java System Property it is replaced by its value in the
41. running VM. For backward compatibility these should be specified without
42. being enclosed in the ${token} replacement syntax. The following properties
43. are translated: * user.home - User's home directory * user.dir - User's current
44. working directory * java.io.tmpdir - Default temp file path * ehcache.disk.store.dir
45. - A system property you would normally specify on the command line e.g. java
46. -Dehcache.disk.store.dir=/u01/myapp/diskdir Subdirectories can be specified
47. below the property e.g. java.io.tmpdir/one -->
48. < diskStore path ="java.io.tmpdir" />
49.
50.
51. <!-- TransactionManagerLookup configuration ======================================
52. This class is used by ehcache to lookup the JTA TransactionManager use in
53. the application using an XA enabled ehcache. If no class is specified then
54. DefaultTransactionManagerLookup will find the TransactionManager in the following
55. order *GenericJNDI (i.e. jboss, where the property jndiName controls the
56. name of the TransactionManager object to look up) *Websphere *Bitronix *Atomikos
57. You can provide you own lookup class that implements the net.sf.ehcache.transaction.manager.TransactionManagerLookup
58. interface. -->
59.
60. < transactionManagerLookup
61. class ="net.sf.ehcache.transaction.manager.DefaultTransactionManagerLookup"
62. properties ="" propertySeparator =":" />
63.
64. <!-- CacheManagerEventListener ========================= Specifies a CacheManagerEventListenerFactory
65. which is notified when Caches are added or removed from the CacheManager.
66. The attributes of CacheManagerEventListenerFactory are: * class - a fully
67. qualified factory class name * properties - comma separated properties having
68. meaning only to the factory. Sets the fully qualified class name to be registered
69. as the CacheManager event listener. The events include: * adding a Cache
70. * removing a Cache Callbacks to listener methods are synchronous and unsynchronized.
71. It is the responsibility of the implementer to safely handle the potential
72. performance and thread safety issues depending on what their listener is
73. doing. If no class is specified, no listener is created. There is no default. -->
74.
75. < cacheManagerEventListenerFactory
76. class ="" properties ="" />
77.
78. <!-- TerracottaConfig ======================== (Enable for Terracotta clustered
79. operation) Note: You need to install and run one or more Terracotta servers
80. to use Terracotta clustering. See http://www.terracotta.org/web/display/orgsite/Download.
81. Specifies a TerracottaConfig which will be used to configure the Terracotta
82. runtime for this CacheManager. Configuration can be specified in two main
83. ways: by reference to a source of configuration or by use of an embedded
84. Terracotta configuration file. To specify a reference to a source (or sources)
85. of configuration, use the url attribute. The url attribute must contain a
86. comma-separated list of: * path to Terracotta configuration file (usually
87. named tc-config.xml) * URL to Terracotta configuration file * <server host>:<port>
88. of running Terracotta Server instance Simplest example for pointing to a
89. Terracotta server on this machine: <terracottaConfig url="localhost:9510"/>
90. Example using a path to Terracotta configuration file: <terracottaConfig
91. url="/app/config/tc-config.xml"/> Example using a URL to a Terracotta configuration
92. file: <terracottaConfig url="http://internal/ehcache/app/tc-config.xml"/>
93. Example using multiple Terracotta server instance URLs (for fault tolerance):
94. <terracottaConfig url="host1:9510,host2:9510,host3:9510"/> To embed a Terracotta
95. configuration file within the ehcache configuration, simply place a normal
96. Terracotta XML config within the <terracottaConfig> element. Example: <terracottaConfig>
97. <tc-config> <servers> <server host="server1" name="s1"/> <server host="server2"
98. name="s2"/> </servers> <clients> <logs>app/logs-%i</logs> </clients> </tc-config>
99. </terracottaConfig> For more information on the Terracotta configuration,
100. see the Terracotta documentation. -->
101.
102.
103. <!-- Cache configuration =================== The following attributes are
104. required. name: Sets the name of the cache. This is used to identify the
105. cache. It must be unique. maxElementsInMemory: Sets the maximum number of
106. objects that will be created in memory maxElementsOnDisk: Sets the maximum
107. number of objects that will be maintained in the DiskStore The default value
108. is zero, meaning unlimited. eternal: Sets whether elements are eternal. If
109. eternal, timeouts are ignored and the element is never expired. overflowToDisk:
110. Sets whether elements can overflow to disk when the memory store has reached
111. the maxInMemory limit. The following attributes and elements are optional.
112. overflowToOffHeap: (boolean) This feature is available only in enterprise
113. versions of Ehcache. When set to true, enables the cache to utilize "off-heap"
114. memory storage to improve performance. Off-heap memory is not subject to
115. Java GC cycles and has a size limit set by the Java property MaxDirectMemorySize.
116. The default value is false. maxMemoryOffHeap: (string) This feature is available
117. only in enterprise versions of Ehcache. Sets the amount of off-heap memory
118. available to the cache. This attribute's values are given as <number>k|K|m|M|g|G|t|T
119. for kilobytes (k|K), megabytes (m|M), gigabytes (g|G), or terrabytes (t|T).
120. For example, maxMemoryOffHeap="2g" allots 2 gigabytes to off-heap memory.
121. In effect only if overflowToOffHeap is true. timeToIdleSeconds: Sets the
122. time to idle for an element before it expires. i.e. The maximum amount of
123. time between accesses before an element expires Is only used if the element
124. is not eternal. Optional attribute. A value of 0 means that an Element can
125. idle for infinity. The default value is 0. timeToLiveSeconds: Sets the time
126. to live for an element before it expires. i.e. The maximum time between creation
127. time and when an element expires. Is only used if the element is not eternal.
128. Optional attribute. A value of 0 means that and Element can live for infinity.
129. The default value is 0. diskPersistent: Whether the disk store persists between
130. restarts of the Virtual Machine. The default value is false. diskExpiryThreadIntervalSeconds:
131. The number of seconds between runs of the disk expiry thread. The default
132. value is 120 seconds. diskSpoolBufferSizeMB: This is the size to allocate
133. the DiskStore for a spool buffer. Writes are made to this area and then asynchronously
134. written to disk. The default size is 30MB. Each spool buffer is used only
135. by its cache. If you get OutOfMemory errors consider lowering this value.
136. To improve DiskStore performance consider increasing it. Trace level logging
137. in the DiskStore will show if put back ups are occurring. clearOnFlush: whether
138. the MemoryStore should be cleared when flush() is called on the cache. By
139. default, this is true i.e. the MemoryStore is cleared. memoryStoreEvictionPolicy:
140. Policy would be enforced upon reaching the maxElementsInMemory limit. Default
141. policy is Least Recently Used (specified as LRU). Other policies available
142. - First In First Out (specified as FIFO) and Less Frequently Used (specified
143. as LFU) Cache elements can also contain sub elements which take the same
144. format of a factory class and properties. Defined sub-elements are: * cacheEventListenerFactory
145. - Enables registration of listeners for cache events, such as put, remove,
146. update, and expire. * bootstrapCacheLoaderFactory - Specifies a BootstrapCacheLoader,
147. which is called by a cache on initialisation to prepopulate itself. * cacheExtensionFactory
148. - Specifies a CacheExtension, a generic mechansim to tie a class which holds
149. a reference to a cache to the cache lifecycle. * cacheExceptionHandlerFactory
150. - Specifies a CacheExceptionHandler, which is called when cache exceptions
151. occur. * cacheLoaderFactory - Specifies a CacheLoader, which can be used
152. both asynchronously and synchronously to load objects into a cache. More
153. than one cacheLoaderFactory element can be added, in which case the loaders
154. form a chain which are executed in order. If a loader returns null, the next
155. in chain is called. Cache Event Listeners All cacheEventListenerFactory elements
156. can take an optional property listenFor that describes which events will
157. be delivered in a clustered environment. The listenFor attribute has the
158. following allowed values: * all - the default is to deliver all local and
159. remote events * local - deliver only events originating in the current node
160. * remote - deliver only events originating in other nodes Example of setting
161. up a logging listener for local cache events: <cacheEventListenerFactory
162. class="my.company.log.CacheLogger" listenFor="local" /> Cache Exception Handling
163. ++++++++++++++++++++++++ By default, most cache operations will propagate
164. a runtime CacheException on failure. An interceptor, using a dynamic proxy,
165. may be configured so that a CacheExceptionHandler can be configured to intercept
166. Exceptions. Errors are not intercepted. It is configured as per the following
167. example: <cacheExceptionHandlerFactory class="com.example.ExampleExceptionHandlerFactory"
168. properties="logLevel=FINE"/> Caches with ExceptionHandling configured are
169. not of type Cache, but are of type Ehcache only, and are not available using
170. CacheManager.getCache(), but using CacheManager.getEhcache(). Cache Loader
171. ++++++++++++ A default CacheLoader may be set which loads objects into the
172. cache through asynchronous and synchronous methods on Cache. This is different
173. to the bootstrap cache loader, which is used only in distributed caching.
174. It is configured as per the following example: <cacheLoaderFactory class="com.example.ExampleCacheLoaderFactory"
175. properties="type=int,startCounter=10"/> XA Cache ++++++++ To enable an ehcache
176. as a participant in the JTA Transaction, just have the following attribute
177. transactionalMode="xa", otherwise the default is transactionalMode="off"
178. Cache Writer ++++++++++++ A CacheWriter maybe be set to write to an underlying
179. resource. Only one CacheWriter can be been to a cache. It is configured as
180. per the following example for write-through: <cacheWriter writeMode="write-through"
181. notifyListenersOnException="true"> <cacheWriterFactory class="net.sf.ehcache.writer.TestCacheWriterFactory"
182. properties="type=int,startCounter=10"/> </cacheWriter> And it is configured
183. as per the following example for write-behind: <cacheWriter writeMode="write-behind"
184. minWriteDelay="1" maxWriteDelay="5" rateLimitPerSecond="5" writeCoalescing="true"
185. writeBatching="true" writeBatchSize="1" retryAttempts="2" retryAttemptDelaySeconds="1">
186. <cacheWriterFactory class="net.sf.ehcache.writer.TestCacheWriterFactory"
187. properties="type=int,startCounter=10"/> </cacheWriter> The cacheWriter element
188. has the following attributes: * writeMode: the write mode, write-through
189. or write-behind These attributes only apply to write-through mode: * notifyListenersOnException:
190. Sets whether to notify listeners when an exception occurs on a writer operation.
191. These attributes only apply to write-behind mode: * minWriteDelay: Set the
192. minimum number of seconds to wait before writing behind. If set to a value
193. greater than 0, it permits operations to build up in the queue. This is different
194. from the maximum write delay in that by waiting a minimum amount of time,
195. work is always being built up. If the minimum write delay is set to zero
196. and the CacheWriter performs its work very quickly, the overhead of processing
197. the write behind queue items becomes very noticeable in a cluster since all
198. the operations might be done for individual items instead of for a collection
199. of them. * maxWriteDelay: Set the maximum number of seconds to wait before
200. writing behind. If set to a value greater than 0, it permits operations to
201. build up in the queue to enable effective coalescing and batching optimisations.
202. * writeBatching: Sets whether to batch write operations. If set to true,
203. writeAll and deleteAll will be called on the CacheWriter rather than write
204. and delete being called for each key. Resources such as databases can perform
205. more efficiently if updates are batched, thus reducing load. * writeBatchSize:
206. Sets the number of operations to include in each batch when writeBatching
207. is enabled. If there are less entries in the write-behind queue than the
208. batch size, the queue length size is used. * rateLimitPerSecond: Sets the
209. maximum number of write operations to allow per second when writeBatching
210. is enabled. * writeCoalescing: Sets whether to use write coalescing. If set
211. to true and multiple operations on the same key are present in the write-behind
212. queue, only the latest write is done, as the others are redundant. * retryAttempts:
213. Sets the number of times the operation is retried in the CacheWriter, this
214. happens after the original operation. * retryAttemptDelaySeconds: Sets the
215. number of seconds to wait before retrying an failed operation. Cache Extension
216. +++++++++++++++ CacheExtensions are a general purpose mechanism to allow
217. generic extensions to a Cache. CacheExtensions are tied into the Cache lifecycle.
218. CacheExtensions are created using the CacheExtensionFactory which has a <code>createCacheCacheExtension()</code>
219. method which takes as a parameter a Cache and properties. It can thus call
220. back into any public method on Cache, including, of course, the load methods.
221. Extensions are added as per the following example: <cacheExtensionFactory
222. class="com.example.FileWatchingCacheRefresherExtensionFactory" properties="refreshIntervalMillis=18000,
223. loaderTimeout=3000, flushPeriod=whatever, someOtherProperty=someValue "/>
224. Terracotta Clustering +++++++++++++++++++++ Cache elements can also contain
225. information about whether the cache can be clustered with Terracotta. The
226. <terracotta> sub-element has the following attributes: * clustered=true|false
227. - indicates whether this cache should be clustered with Terracotta. By default,
228. if the <terracotta> element is included, clustered=true. * valueMode=serialization|identity
229. - indicates whether this cache should be clustered with serialized copies
230. of the values or using Terracotta identity mode. By default, values will
231. be cached in serialization mode which is similar to other replicated Ehcache
232. modes. The identity mode is only available in certain Terracotta deployment
233. scenarios and will maintain actual object identity of the keys and values
234. across the cluster. In this case, all users of a value retrieved from the
235. cache are using the same clustered value and must provide appropriate locking
236. for any changes made to the value (or objects referred to by the value).
237. * synchronousWrites=true|false - When set to true, clustered caches use Terracotta
238. SYNCHRONOUS WRITE locks. Asynchronous writes (synchronousWrites="false")
239. maximize performance by allowing clients to proceed without waiting for a
240. "transaction received" acknowledgement from the server. Synchronous writes
241. (synchronousWrites="true") maximize data safety by requiring that a client
242. receive server acknowledgement of a transaction before that client can proceed.
243. If coherence mode is disabled using configuration (coherent="false") or through
244. the coherence API, only asynchronous writes can occur (synchronousWrites="true"
245. is ignored). By default this value is false (i.e. clustered caches use normal
246. Terracotta WRITE locks). * coherent=true|false - indicates whether this cache
247. should have coherent reads and writes with guaranteed consistency across
248. the cluster. By default, its value is true. If this attribute is set to false
249. (or "incoherent" mode), values from the cache are read without locking, possibly
250. yielding stale data. Writes to a cache in incoherent mode are batched and
251. applied without acquiring cluster-wide locks, possibly creating inconsistent
252. values across cluster. Incoherent mode is a performance optimization with
253. weaker concurrency guarantees and should generally be used for bulk-loading
254. caches, for loading a read-only cache, or where the application that can
255. tolerate reading stale data. This setting overrides coherentReads, which
256. is deprecated. * copyOnRead=true|false - indicates whether cache values are
257. deserialized on every read or if the materialized cache value can be re-used
258. between get() calls. This setting is useful if a cache is being shared by
259. callers with disparate classloaders or to prevent local drift if keys/values
260. are mutated locally w/o putting back to the cache. NOTE: This setting is
261. only relevant for caches with valueMode=serialization Simplest example to
262. indicate clustering: <terracotta/> To indicate the cache should not be clustered
263. (or remove the <terracotta> element altogether): <terracotta clustered="false"/>
264. To indicate the cache should be clustered using identity mode: <terracotta
265. clustered="true" valueMode="identity"/> To indicate the cache should be clustered
266. using incoherent mode for bulk load: <terracotta clustered="true" coherent="false"/>
267. To indicate the cache should be clustered using synchronous-write locking
268. level: <terracotta clustered="true" synchronousWrites="true"/> -->
269.
270. <!-- Mandatory Default Cache configuration. These settings will be applied
271. to caches created programmtically using CacheManager.add(String cacheName).
272. The defaultCache has an implicit name "default" which is a reserved cache
273. name. -->
274. < defaultCache maxElementsInMemory ="0" eternal ="false"
275. overflowToDisk ="true" timeToIdleSeconds ="1200" timeToLiveSeconds ="1200" >
276.
277. </ defaultCache >
278.
279. <!-- Sample caches. Following are some example caches. Remove these before
280. use. -->
281.
282. <!-- Sample cache named sampleCache1 This cache contains a maximum in memory
283. of 10000 elements, and will expire an element if it is idle for more than
284. 5 minutes and lives for more than 10 minutes. If there are more than 10000
285. elements it will overflow to the disk cache, which in this configuration
286. will go to wherever java.io.tmp is defined on your system. On a standard
287. Linux system this will be /tmp" -->
288. < cache name ="sampleCache1" maxElementsInMemory ="10000"
289. maxElementsOnDisk ="1000" eternal ="false" overflowToDisk ="true"
290. diskSpoolBufferSizeMB ="20" timeToIdleSeconds ="300" timeToLiveSeconds ="600"
291. memoryStoreEvictionPolicy ="LFU" />
292.
293.
294. <!-- Sample cache named sampleCache2 This cache has a maximum of 1000 elements
295. in memory. There is no overflow to disk, so 1000 is also the maximum cache
296. size. Note that when a cache is eternal, timeToLive and timeToIdle are not
297. used and do not need to be specified. -->
298. < cache name ="sampleCache2" maxElementsInMemory ="1000" eternal ="true"
299. overflowToDisk ="false" memoryStoreEvictionPolicy ="FIFO" />
300.
301.
302. <!-- Sample cache named sampleCache3. This cache overflows to disk. The
303. disk store is persistent between cache and VM restarts. The disk expiry thread
304. interval is set to 10 minutes, overriding the default of 2 minutes. -->
305. < cache name ="sampleCache3" maxElementsInMemory ="500" eternal ="false"
306. overflowToDisk ="true" timeToIdleSeconds ="300" timeToLiveSeconds ="600"
307. diskPersistent ="true" diskExpiryThreadIntervalSeconds ="1"
308. memoryStoreEvictionPolicy ="LFU" />
309.
310. <!-- Sample Terracotta clustered cache named sampleTerracottaCache. This
311. cache uses Terracotta to cluster the contents of the cache. -->
312. < cache name ="sampleTerracottaCache" maxElementsInMemory ="1000"
313. eternal ="false" timeToIdleSeconds ="3600" timeToLiveSeconds ="1800"
314. overflowToDisk ="false" >
315.
316.
317. </ cache >
318.
319. <!-- Sample xa enabled cache name xaCache -->
320.
321. < cache name ="xaCache" maxElementsInMemory ="500" eternal ="false"
322. timeToIdleSeconds ="300" timeToLiveSeconds ="600" overflowToDisk ="false"
323. diskPersistent ="false" diskExpiryThreadIntervalSeconds ="1" >
324.
325. </ cache >
326.
327.
328. </ ehcache >
操作类实例
01
.
package
com.rx;
02 .
03 . import java.io.Serializable;
04 .
05 . import net.sf.ehcache.Cache;
06 . import net.sf.ehcache.CacheManager;
07 . import net.sf.ehcache.Element;
08 .
09 . public class EhCache {
10 .
11 . /**
12. * @param args
13. */
14 . public static void main(String[] args) {
15 . System.out.println( 1 );
16 . // CacheManager manager = new CacheManager();
17 .
18 . CacheManager singletonManager = CacheManager.create();
19 . Cache memoryOnlyCache = new Cache( " testCache " , 5000 , false , false , 5 , 2 );
20 . singletonManager.addCache(memoryOnlyCache);
21 . Cache cache = singletonManager.getCache( " testCache " );
22 .
23 . Element element = new Element( " key1 " , " value1 " );
24 . cache.put(element);
25 . cache.put( new Element( " key1 " , " value2 " ));
26 .
27 . element = cache.get( " key1 " );
28 . Serializable value = element.getValue();
29 . System.out.println(value);
30 .
31 . int elementsInMemory = cache.getSize();
32 . System.out.println(elementsInMemory);
33 .
34 . long elementsInMemory2 = cache.getMemoryStoreSize();
35 . System.out.println(elementsInMemory2);
36 .
37 . Object obj = element.getObjectValue();
38 . cache.remove( " key1 " );
39 . System.out.println(obj);
40 . singletonManager.shutdown();
41 . // manager.shutdown();
42 .
43 . System.out.println( 2 );
44 .
45 . }
46 .
47 .}
02 .
03 . import java.io.Serializable;
04 .
05 . import net.sf.ehcache.Cache;
06 . import net.sf.ehcache.CacheManager;
07 . import net.sf.ehcache.Element;
08 .
09 . public class EhCache {
10 .
11 . /**
12. * @param args
13. */
14 . public static void main(String[] args) {
15 . System.out.println( 1 );
16 . // CacheManager manager = new CacheManager();
17 .
18 . CacheManager singletonManager = CacheManager.create();
19 . Cache memoryOnlyCache = new Cache( " testCache " , 5000 , false , false , 5 , 2 );
20 . singletonManager.addCache(memoryOnlyCache);
21 . Cache cache = singletonManager.getCache( " testCache " );
22 .
23 . Element element = new Element( " key1 " , " value1 " );
24 . cache.put(element);
25 . cache.put( new Element( " key1 " , " value2 " ));
26 .
27 . element = cache.get( " key1 " );
28 . Serializable value = element.getValue();
29 . System.out.println(value);
30 .
31 . int elementsInMemory = cache.getSize();
32 . System.out.println(elementsInMemory);
33 .
34 . long elementsInMemory2 = cache.getMemoryStoreSize();
35 . System.out.println(elementsInMemory2);
36 .
37 . Object obj = element.getObjectValue();
38 . cache.remove( " key1 " );
39 . System.out.println(obj);
40 . singletonManager.shutdown();
41 . // manager.shutdown();
42 .
43 . System.out.println( 2 );
44 .
45 . }
46 .
47 .}
转自: http://blog.csdn.net/longronglin/article/details/6699641
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