/*
* Copyright 2002-2009 the original author or authors.
*
* 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.springframework.cache.ehcache;
import java.io.IOException;
import java.util.Set;
import net.sf.ehcache.Cache;
import net.sf.ehcache.CacheException;
import net.sf.ehcache.CacheManager;
import net.sf.ehcache.Ehcache;
import net.sf.ehcache.bootstrap.BootstrapCacheLoader;
import net.sf.ehcache.constructs.blocking.BlockingCache;
import net.sf.ehcache.constructs.blocking.CacheEntryFactory;
import net.sf.ehcache.constructs.blocking.SelfPopulatingCache;
import net.sf.ehcache.constructs.blocking.UpdatingCacheEntryFactory;
import net.sf.ehcache.constructs.blocking.UpdatingSelfPopulatingCache;
import net.sf.ehcache.event.CacheEventListener;
import net.sf.ehcache.store.MemoryStoreEvictionPolicy;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.beans.factory.BeanNameAware;
import org.springframework.beans.factory.FactoryBean;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.util.Assert;
/**
* {@link FactoryBean} that creates a named EHCache {@link net.sf.ehcache.Cache} instance
* (or a decorator that implements the {@link net.sf.ehcache.Ehcache} interface),
* representing a cache region within an EHCache {@link net.sf.ehcache.CacheManager}.
*
* <p>If the specified named cache is not configured in the cache configuration descriptor,
* this FactoryBean will construct an instance of a Cache with the provided name and the
* specified cache properties and add it to the CacheManager for later retrieval. If some
* or all properties are not set at configuration time, this FactoryBean will use defaults.
*
* <p>Note: If the named Cache instance is found, the properties will be ignored and the
* Cache instance will be retrieved from the CacheManager.
*
* <p>Note: As of Spring 3.0, Spring's EHCache support requires EHCache 1.3 or higher.
* @author Dmitriy Kopylenko
* @author Juergen Hoeller
* @since 1.1.1
* @see #setCacheManager
* @see EhCacheManagerFactoryBean
* @see net.sf.ehcache.Cache
*/
public class EhCacheFactoryBean implements FactoryBean<Ehcache>, BeanNameAware, InitializingBean {
protected final Log logger = LogFactory.getLog(getClass());
private CacheManager cacheManager;
private String cacheName;
private int maxElementsInMemory = 10000;
private int maxElementsOnDisk = 10000000;
private MemoryStoreEvictionPolicy memoryStoreEvictionPolicy = MemoryStoreEvictionPolicy.LRU;
private boolean overflowToDisk = true;
private boolean eternal = false;
private int timeToLive = 120;
private int timeToIdle = 120;
private boolean diskPersistent = false;
private int diskExpiryThreadIntervalSeconds = 120;
private int diskSpoolBufferSize = 0;
private boolean clearOnFlush = true;
private boolean blocking = false;
private CacheEntryFactory cacheEntryFactory;
private BootstrapCacheLoader bootstrapCacheLoader;
private Set<CacheEventListener> cacheEventListeners;
private String beanName;
private Ehcache cache;
/**
* Set a CacheManager from which to retrieve a named Cache instance.
* By default, <code>CacheManager.getInstance()</code> will be called.
* <p>Note that in particular for persistent caches, it is advisable to
* properly handle the shutdown of the CacheManager: Set up a separate
* EhCacheManagerFactoryBean and pass a reference to this bean property.
* <p>A separate EhCacheManagerFactoryBean is also necessary for loading
* EHCache configuration from a non-default config location.
* @see EhCacheManagerFactoryBean
* @see net.sf.ehcache.CacheManager#getInstance
*/
public void setCacheManager(CacheManager cacheManager) {
this.cacheManager = cacheManager;
}
/**
* Set a name for which to retrieve or create a cache instance.
* Default is the bean name of this EhCacheFactoryBean.
*/
public void setCacheName(String cacheName) {
this.cacheName = cacheName;
}
/**
* Specify the maximum number of cached objects in memory.
* Default is 10000 elements.
*/
public void setMaxElementsInMemory(int maxElementsInMemory) {
this.maxElementsInMemory = maxElementsInMemory;
}
/**
* Specify the maximum number of cached objects on disk.
* Default is 10000000 elements.
*/
public void setMaxElementsOnDisk(int maxElementsOnDisk) {
this.maxElementsOnDisk = maxElementsOnDisk;
}
/**
* Set the memory style eviction policy for this cache.
* <p>Supported values are "LRU", "LFU" and "FIFO", according to the
* constants defined in EHCache's MemoryStoreEvictionPolicy class.
* Default is "LRU".
*/
public void setMemoryStoreEvictionPolicy(MemoryStoreEvictionPolicy memoryStoreEvictionPolicy) {
Assert.notNull(memoryStoreEvictionPolicy, "memoryStoreEvictionPolicy must not be null");
this.memoryStoreEvictionPolicy = memoryStoreEvictionPolicy;
}
/**
* Set whether elements can overflow to disk when the in-memory cache
* has reached the maximum size limit. Default is "true".
*/
public void setOverflowToDisk(boolean overflowToDisk) {
this.overflowToDisk = overflowToDisk;
}
/**
* Set whether elements are considered as eternal. If "true", timeouts
* are ignored and the element is never expired. Default is "false".
*/
public void setEternal(boolean eternal) {
this.eternal = eternal;
}
/**
* Set the time in seconds to live for an element before it expires,
* i.e. the maximum time between creation time and when an element expires.
* <p>This is only used if the element is not eternal. Default is 120 seconds.
*/
public void setTimeToLive(int timeToLive) {
this.timeToLive = timeToLive;
}
/**
* Set the time in seconds to idle for an element before it expires, that is,
* the maximum amount of time between accesses before an element expires.
* <p>This is only used if the element is not eternal. Default is 120 seconds.
*/
public void setTimeToIdle(int timeToIdle) {
this.timeToIdle = timeToIdle;
}
/**
* Set whether the disk store persists between restarts of the Virtual Machine.
* Default is "false".
*/
public void setDiskPersistent(boolean diskPersistent) {
this.diskPersistent = diskPersistent;
}
/**
* Set the number of seconds between runs of the disk expiry thread.
* Default is 120 seconds.
*/
public void setDiskExpiryThreadIntervalSeconds(int diskExpiryThreadIntervalSeconds) {
this.diskExpiryThreadIntervalSeconds = diskExpiryThreadIntervalSeconds;
}
/**
* Set the amount of memory to allocate the write buffer for puts to the disk store.
* Default is 0.
*/
public void setDiskSpoolBufferSize(int diskSpoolBufferSize) {
this.diskSpoolBufferSize = diskSpoolBufferSize;
}
/**
* Set whether the memory store should be cleared when flush is called on the cache.
* Default is "true".
*/
public void setClearOnFlush(boolean clearOnFlush) {
this.clearOnFlush = clearOnFlush;
}
/**
* Set whether to use a blocking cache that lets read attempts block
* until the requested element is created.
* <p>If you intend to build a self-populating blocking cache,
* consider specifying a {@link #setCacheEntryFactory CacheEntryFactory}.
* @see net.sf.ehcache.constructs.blocking.BlockingCache
* @see #setCacheEntryFactory
*/
public void setBlocking(boolean blocking) {
this.blocking = blocking;
}
/**
* Set an EHCache {@link net.sf.ehcache.constructs.blocking.CacheEntryFactory}
* to use for a self-populating cache. If such a factory is specified,
* the cache will be decorated with EHCache's
* {@link net.sf.ehcache.constructs.blocking.SelfPopulatingCache}.
* <p>The specified factory can be of type
* {@link net.sf.ehcache.constructs.blocking.UpdatingCacheEntryFactory},
* which will lead to the use of an
* {@link net.sf.ehcache.constructs.blocking.UpdatingSelfPopulatingCache}.
* <p>Note: Any such self-populating cache is automatically a blocking cache.
* @see net.sf.ehcache.constructs.blocking.SelfPopulatingCache
* @see net.sf.ehcache.constructs.blocking.UpdatingSelfPopulatingCache
* @see net.sf.ehcache.constructs.blocking.UpdatingCacheEntryFactory
*/
public void setCacheEntryFactory(CacheEntryFactory cacheEntryFactory) {
this.cacheEntryFactory = cacheEntryFactory;
}
/**
* Set an EHCache {@link net.sf.ehcache.bootstrap.BootstrapCacheLoader}
* for this cache, if any.
*/
public void setBootstrapCacheLoader(BootstrapCacheLoader bootstrapCacheLoader) {
this.bootstrapCacheLoader = bootstrapCacheLoader;
}
/**
* Specify EHCache {@link net.sf.ehcache.event.CacheEventListener cache event listeners}
* to registered with this cache.
*/
public void setCacheEventListeners(Set<CacheEventListener> cacheEventListeners) {
this.cacheEventListeners = cacheEventListeners;
}
public void setBeanName(String name) {
this.beanName = name;
}
public void afterPropertiesSet() throws CacheException, IOException {
// If no CacheManager given, fetch the default.
if (this.cacheManager == null) {
if (logger.isDebugEnabled()) {
logger.debug("Using default EHCache CacheManager for cache region '" + this.cacheName + "'");
}
this.cacheManager = CacheManager.getInstance();
}
// If no cache name given, use bean name as cache name.
if (this.cacheName == null) {
this.cacheName = this.beanName;
}
// Fetch cache region: If none with the given name exists,
// create one on the fly.
Ehcache rawCache;
if (this.cacheManager.cacheExists(this.cacheName)) {
if (logger.isDebugEnabled()) {
logger.debug("Using existing EHCache cache region '" + this.cacheName + "'");
}
rawCache = this.cacheManager.getEhcache(this.cacheName);
}
else {
if (logger.isDebugEnabled()) {
logger.debug("Creating new EHCache cache region '" + this.cacheName + "'");
}
rawCache = createCache();
this.cacheManager.addCache(rawCache);
}
// Decorate cache if necessary.
Ehcache decoratedCache = decorateCache(rawCache);
if (decoratedCache != rawCache) {
this.cacheManager.replaceCacheWithDecoratedCache(rawCache, decoratedCache);
}
this.cache = decoratedCache;
}
/**
* Create a raw Cache object based on the configuration of this FactoryBean.
*/
protected Cache createCache() {
// Only call EHCache 1.6 constructor if actually necessary (for compatibility with EHCache 1.3+)
Cache cache = (!this.clearOnFlush) ?
new Cache(this.cacheName, this.maxElementsInMemory, this.memoryStoreEvictionPolicy,
this.overflowToDisk, null, this.eternal, this.timeToLive, this.timeToIdle,
this.diskPersistent, this.diskExpiryThreadIntervalSeconds, null,
this.bootstrapCacheLoader, this.maxElementsOnDisk, this.diskSpoolBufferSize,
this.clearOnFlush) :
new Cache(this.cacheName, this.maxElementsInMemory, this.memoryStoreEvictionPolicy,
this.overflowToDisk, null, this.eternal, this.timeToLive, this.timeToIdle,
this.diskPersistent, this.diskExpiryThreadIntervalSeconds, null,
this.bootstrapCacheLoader, this.maxElementsOnDisk, this.diskSpoolBufferSize);
if (this.cacheEventListeners != null) {
for (CacheEventListener listener : this.cacheEventListeners) {
cache.getCacheEventNotificationService().registerListener(listener);
}
}
return cache;
}
/**
* Decorate the given Cache, if necessary.
* @param cache the raw Cache object, based on the configuration of this FactoryBean
* @return the (potentially decorated) cache object to be registered with the CacheManager
*/
protected Ehcache decorateCache(Ehcache cache) {
if (this.cacheEntryFactory != null) {
if (this.cacheEntryFactory instanceof UpdatingCacheEntryFactory) {
return new UpdatingSelfPopulatingCache(cache, (UpdatingCacheEntryFactory) this.cacheEntryFactory);
}
else {
return new SelfPopulatingCache(cache, this.cacheEntryFactory);
}
}
if (this.blocking) {
return new BlockingCache(cache);
}
return cache;
}
public Ehcache getObject() {
return this.cache;
}
public Class<? extends Ehcache> getObjectType() {
return (this.cache != null ? this.cache.getClass() : Ehcache.class);
}
public boolean isSingleton() {
return true;
}
}
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