/*
* Hibernate, Relational Persistence for Idiomatic Java
*
* Copyright (c) 2007, Red Hat Middleware LLC or third-party contributors as
* indicated by the @author tags or express copyright attribution
* statements applied by the authors. All third-party contributions are
* distributed under license by Red Hat Middleware LLC.
*
* This copyrighted material is made available to anyone wishing to use, modify,
* copy, or redistribute it subject to the terms and conditions of the GNU
* Lesser General Public License, as published by the Free Software Foundation.
*
* This program 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 distribution; if not, write to:
* Free Software Foundation, Inc.
* 51 Franklin Street, Fifth Floor
* Boston, MA 02110-1301 USA
*/
package org.hibernate.cache.jbc2.timestamp;
import java.util.Map;
import java.util.Properties;
import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;
import javax.transaction.Transaction;
import org.hibernate.cache.CacheException;
import org.hibernate.cache.TimestampsRegion;
import org.hibernate.cache.jbc2.TransactionalDataRegionAdapter;
import org.hibernate.cache.jbc2.util.CacheHelper;
import org.jboss.cache.Cache;
import org.jboss.cache.Fqn;
import org.jboss.cache.config.Option;
import org.jboss.cache.notifications.annotation.CacheListener;
import org.jboss.cache.notifications.annotation.NodeModified;
import org.jboss.cache.notifications.annotation.NodeRemoved;
import org.jboss.cache.notifications.event.NodeInvalidatedEvent;
import org.jboss.cache.notifications.event.NodeModifiedEvent;
import org.jboss.cache.notifications.event.NodeRemovedEvent;
/**
* Defines the behavior of the timestamps cache region for JBossCache 2.x.
*
* TODO Need to define a way to ensure asynchronous replication events
* do not result in timestamps moving backward, while dealing with the fact
* that the normal sequence of UpdateTimestampsCache.preinvalidate() then
* UpdateTimestampsCache.invalidate() will result in 2 calls to put() with
* the latter call having an earlier timestamp.
*
* @author Brian Stansberry
* @version $Revision: 17811 $
*/
@CacheListener
public class TimestampsRegionImpl extends TransactionalDataRegionAdapter implements TimestampsRegion {
public static final String TYPE = "TS";
private Map localCache = new ConcurrentHashMap();
/**
* Create a new TimestampsRegionImpl.
*
* @param jbcCache The JBC cache instance to use to store the timestamps data
* @param regionName The name of the region (within the JBC cache)
* @param regionPrefix Any region prefix to apply
* @param properties The configuration properties.
*/
public TimestampsRegionImpl(Cache jbcCache, String regionName, String regionPrefix, Properties properties) {
super(jbcCache, regionName, regionPrefix, null);
jbcCache.addCacheListener(this);
populateLocalCache();
}
@Override
protected Fqn<String> createRegionFqn(String regionName, String regionPrefix) {
return getTypeFirstRegionFqn(regionName, regionPrefix, TYPE);
}
public void evict(Object key) throws CacheException {
ensureRegionRootExists();
// TODO Is this a valid operation on a timestamps cache?
Option opt = getNonLockingDataVersionOption(true);
CacheHelper.removeNode(getCacheInstance(), getRegionFqn(), key, opt);
}
public void evictAll() throws CacheException {
// TODO Is this a valid operation on a timestamps cache?
Transaction tx = suspend();
try {
ensureRegionRootExists();
Option opt = getNonLockingDataVersionOption(true);
CacheHelper.sendEvictAllNotification(jbcCache, regionFqn, getMemberId(), opt);
}
finally {
resume(tx);
}
}
public Object get(Object key) throws CacheException {
Object value = localCache.get(key);
if (value == null && checkValid()) {
ensureRegionRootExists();
value = suspendAndGet(key, null, false);
if (value != null)
localCache.put(key, value);
}
return value;
}
public void put(Object key, Object value) throws CacheException {
ensureRegionRootExists();
// Don't hold the JBC node lock throughout the tx, as that
// prevents reads and other updates
Transaction tx = suspend();
try {
// TODO Why not use the timestamp in a DataVersion?
Option opt = getNonLockingDataVersionOption(false);
// We ensure ASYNC semantics (JBCACHE-1175)
opt.setForceAsynchronous(true);
CacheHelper.put(getCacheInstance(), getRegionFqn(), key, value, opt);
} catch (Exception e) {
throw new CacheException(e);
} finally {
resume(tx);
}
}
@Override
public void destroy() throws CacheException {
localCache.clear();
getCacheInstance().removeCacheListener(this);
super.destroy();
}
/**
* Monitors cache events and updates the local cache
*
* @param event
*/
@NodeModified
public void nodeModified(NodeModifiedEvent event) {
if (!handleEvictAllModification(event) && !event.isPre()) {
Fqn fqn = event.getFqn();
Fqn regFqn = getRegionFqn();
if (fqn.size() == regFqn.size() + 1 && fqn.isChildOf(regFqn)) {
Object key = fqn.get(regFqn.size());
localCache.put(key, event.getData().get(ITEM));
}
}
}
/**
* Monitors cache events and updates the local cache
*
* @param event
*/
@NodeRemoved
public void nodeRemoved(NodeRemovedEvent event) {
if (event.isPre())
return;
Fqn fqn = event.getFqn();
Fqn regFqn = getRegionFqn();
if (fqn.size() == regFqn.size() + 1 && fqn.isChildOf(regFqn)) {
Object key = fqn.get(regFqn.size());
localCache.remove(key);
}
else if (fqn.equals(regFqn)) {
localCache.clear();
}
}
@Override
protected boolean handleEvictAllInvalidation(NodeInvalidatedEvent event)
{
boolean result = super.handleEvictAllInvalidation(event);
if (result) {
localCache.clear();
}
return result;
}
@Override
protected boolean handleEvictAllModification(NodeModifiedEvent event)
{
boolean result = super.handleEvictAllModification(event);
if (result) {
localCache.clear();
}
return result;
}
/**
* Brings all data from the distributed cache into our local cache.
*/
private void populateLocalCache() {
Set children = CacheHelper.getChildrenNames(getCacheInstance(), getRegionFqn());
for (Object key : children) {
get(key);
}
}
}