/*
* Copyright (C) 2009 eXo Platform SAS.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.exoplatform.services.cache.impl.jboss.lru;
import org.exoplatform.management.annotations.Managed;
import org.exoplatform.management.annotations.ManagedDescription;
import org.exoplatform.management.annotations.ManagedName;
import org.exoplatform.services.cache.ExoCache;
import org.exoplatform.services.cache.ExoCacheConfig;
import org.exoplatform.services.cache.ExoCacheInitException;
import org.exoplatform.services.cache.impl.jboss.AbstractExoCache;
import org.exoplatform.services.cache.impl.jboss.AbstractExoCacheCreator;
import org.jboss.cache.Cache;
import org.jboss.cache.Fqn;
import org.jboss.cache.eviction.LRUAlgorithmConfig;
import java.io.Serializable;
/**
* The LRU Implementation of an {@link org.exoplatform.services.cache.impl.jboss.ExoCacheCreator}
* Created by The eXo Platform SAS
* Author : eXoPlatform
* exo@exoplatform.com
* 21 juil. 2009
*/
public class LRUExoCacheCreator extends AbstractExoCacheCreator
{
/**
* The expected implementation name
*/
public static final String EXPECTED_IMPL = "LRU";
/**
* The default value for the parameter timeToLive
*/
protected long defaultTimeToLive;
/**
* The default value for the parameter maxAge
*/
protected long defaultMaxAge;
/**
* {@inheritDoc}
*/
public ExoCache<Serializable, Object> create(ExoCacheConfig config, Cache<Serializable, Object> cache)
throws ExoCacheInitException
{
if (config instanceof LRUExoCacheConfig)
{
final LRUExoCacheConfig lruConfig = (LRUExoCacheConfig)config;
return create(config, cache, lruConfig.getMaxNodes(), lruConfig.getTimeToLive(), lruConfig.getMaxAge(),
lruConfig.getMinTimeToLive());
}
else
{
final long period = config.getLiveTime();
return create(config, cache, config.getMaxSize(), defaultTimeToLive, defaultMaxAge, period > 0 ? period * 1000
: 0);
}
}
/**
* Creates a new ExoCache instance with the relevant parameters
*/
private ExoCache<Serializable, Object> create(ExoCacheConfig config, Cache<Serializable, Object> cache,
int maxNodes, long timeToLive, long maxAge, long minTimeToLive) throws ExoCacheInitException
{
final LRUAlgorithmConfig lru = new LRUAlgorithmConfig(timeToLive, maxAge, maxNodes);
lru.setMinTimeToLive(minTimeToLive);
Fqn<String> rooFqn = addEvictionRegion(config, cache, lru);
return new LRUExoCache(config, cache, rooFqn, lru);
}
/**
* {@inheritDoc}
*/
public Class<? extends ExoCacheConfig> getExpectedConfigType()
{
return LRUExoCacheConfig.class;
}
/**
* {@inheritDoc}
*/
public String getExpectedImplementation()
{
return EXPECTED_IMPL;
}
/**
* The LRU implementation of an ExoCache
*/
public static class LRUExoCache extends AbstractExoCache<Serializable, Object>
{
private final LRUAlgorithmConfig lru;
public LRUExoCache(ExoCacheConfig config, Cache<Serializable, Object> cache, Fqn<String> rooFqn,
LRUAlgorithmConfig lru)
{
super(config, cache, rooFqn);
this.lru = lru;
}
@ManagedName("MinTimeToLive")
@ManagedDescription("the minimum amount of time a node must be allowed to live after" +
" being accessed before it is allowed to be considered for eviction. 0 denotes " +
"that this feature is disabled, which is the default value.")
public long getLiveTime()
{
return lru.getMinTimeToLive();
}
@ManagedName("MaxNodes")
@ManagedDescription("This is the maximum number of nodes allowed in this region. " +
"0 denotes immediate expiry, -1 denotes no limit.")
public int getMaxSize()
{
return lru.getMaxNodes();
}
@Managed
@ManagedName("TimeToLive")
@ManagedDescription("The amount of time a node is not written to or read (in milliseconds) " +
"before the node is swept away. 0 denotes immediate expiry, -1 denotes no limit.")
public long getTimeToLive()
{
return lru.getTimeToLive();
}
@Managed
@ManagedName("MaxAges")
@ManagedDescription("Lifespan of a node (in milliseconds) regardless of idle time before " +
"the node is swept away. 0 denotes immediate expiry, -1 denotes no limit.")
public long getMaxAge()
{
return lru.getMaxAge();
}
public void setLiveTime(long period)
{
lru.setMinTimeToLive(period);
}
public void setMaxSize(int max)
{
lru.setMaxNodes(max);
}
@Managed
public void setTimeToLive(long timeToLive)
{
lru.setTimeToLive(timeToLive);
}
@Managed
public void setMaxAge(long maxAge)
{
lru.setMaxAge(maxAge);
}
}
}