/*
* Copyright (c) 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017 David Berkman
*
* This file is part of the SmallMind Code Project.
*
* The SmallMind Code Project is free software, you can redistribute
* it and/or modify it under either, at your discretion...
*
* 1) The terms of GNU Affero General Public License as published by the
* Free Software Foundation, either version 3 of the License, or (at
* your option) any later version.
*
* ...or...
*
* 2) The terms of the Apache License, Version 2.0.
*
* The SmallMind Code Project 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 or Apache License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* and the Apache License along with the SmallMind Code Project. If not, see
* <http://www.gnu.org/licenses/> or <http://www.apache.org/licenses/LICENSE-2.0>.
*
* Additional permission under the GNU Affero GPL version 3 section 7
* ------------------------------------------------------------------
* If you modify this Program, or any covered work, by linking or
* combining it with other code, such other code is not for that reason
* alone subject to any of the requirements of the GNU Affero GPL
* version 3.
*/
package org.smallmind.persistence.cache.ehcache;
import java.util.HashMap;
import java.util.Map;
import net.sf.ehcache.Cache;
import net.sf.ehcache.Element;
import org.smallmind.persistence.cache.CASValue;
import org.smallmind.persistence.cache.CacheOperationException;
import org.smallmind.persistence.cache.PersistenceCache;
public class EhcacheCache<V> implements PersistenceCache<String, V> {
private static final CASValue EMPTY_CAS_VALUE = new CASValue<Object>(null, 0);
private Cache ehCache;
private Class<V> valueClass;
public EhcacheCache (Cache ehCache, Class<V> valueClass) {
this.ehCache = ehCache;
this.valueClass = valueClass;
}
private Element createElement (String key, V value, int timeToLiveSeconds) {
return new Element(key, value, false, (int)ehCache.getCacheConfiguration().getTimeToIdleSeconds(), (timeToLiveSeconds <= 0) ? (int)ehCache.getCacheConfiguration().getTimeToLiveSeconds() : timeToLiveSeconds);
}
@Override
public boolean requiresCopyOnDistributedCASOperation () {
return true;
}
@Override
public int getDefaultTimeToLiveSeconds () {
return (int)ehCache.getCacheConfiguration().getTimeToLiveSeconds();
}
@Override
public V get (String key) {
return valueClass.cast(ehCache.get(key).getValue());
}
@Override
public Map<String, V> get (String[] keys)
throws CacheOperationException {
HashMap<String, V> resultMap = new HashMap<String, V>();
for (String key : keys) {
V value;
if ((value = valueClass.cast(ehCache.get(key).getValue())) != null) {
resultMap.put(key, value);
}
}
return resultMap;
}
@Override
public void set (String key, V value, int timeToLiveSeconds) {
ehCache.put(createElement(key, value, timeToLiveSeconds));
}
@Override
public V putIfAbsent (String key, V value, int timeToLiveSeconds) {
return valueClass.cast(ehCache.putIfAbsent(createElement(key, value, timeToLiveSeconds)).getValue());
}
@Override
public CASValue<V> getViaCas (String key) {
Element element;
if ((element = ehCache.get(key)) != null) {
return new CASValue<V>(valueClass.cast(element.getValue()), element.getVersion());
}
return EMPTY_CAS_VALUE;
}
@Override
public boolean putViaCas (String key, V oldValue, V value, long version, int timeToLiveSeconds) {
if (oldValue == null) {
return ehCache.putIfAbsent(createElement(key, value, timeToLiveSeconds)) == null;
}
else {
return ehCache.replace(createElement(key, oldValue, timeToLiveSeconds), createElement(key, value, timeToLiveSeconds));
}
}
@Override
public void remove (String key) {
ehCache.remove(key);
}
}