//$Id: OptimisticTreeCacheProvider.java 18072 2009-11-26 20:28:45Z stliu $
package org.hibernate.cache;
import java.util.Properties;
import javax.transaction.TransactionManager;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.hibernate.cfg.Environment;
import org.hibernate.transaction.TransactionManagerLookup;
import org.hibernate.transaction.TransactionManagerLookupFactory;
import org.jboss.cache.PropertyConfigurator;
/**
* Support for a standalone JBossCache TreeCache instance utilizing TreeCache's
* optimistic locking capabilities. This capability was added in JBossCache
* version 1.3.0; as such this provider will only work with that version or
* higher.
* <p/>
* The TreeCache instance is configured via a local config resource. The
* resource to be used for configuration can be controlled by specifying a value
* for the {@link #CONFIG_RESOURCE} config property.
*
* @author Steve Ebersole
*/
public class OptimisticTreeCacheProvider implements CacheProvider {
/**
* @deprecated use {@link Environment#CACHE_PROVIDER_CONFIG}
*/
public static final String CONFIG_RESOURCE = "hibernate.cache.opt_tree_cache.config";
public static final String DEFAULT_CONFIG = "treecache.xml";
private static final String NODE_LOCKING_SCHEME = "OPTIMISTIC";
private static final Log log = LogFactory.getLog( OptimisticTreeCacheProvider.class );
private org.jboss.cache.TreeCache cache;
/**
* Construct and configure the Cache representation of a named cache region.
*
* @param regionName the name of the cache region
* @param properties configuration settings
* @return The Cache representation of the named cache region.
* @throws CacheException
* Indicates an error building the cache region.
*/
public Cache buildCache(String regionName, Properties properties) throws CacheException {
return new OptimisticTreeCache( cache, regionName );
}
public long nextTimestamp() {
return System.currentTimeMillis() / 100;
}
/**
* Prepare the underlying JBossCache TreeCache instance.
*
* @param properties All current config settings.
* @throws CacheException
* Indicates a problem preparing cache for use.
*/
public void start(Properties properties) {
String resource = properties.getProperty( Environment.CACHE_PROVIDER_CONFIG );
if (resource == null) {
resource = properties.getProperty( CONFIG_RESOURCE );
}
if ( resource == null ) {
resource = DEFAULT_CONFIG;
}
log.debug( "Configuring TreeCache from resource [" + resource + "]" );
try {
cache = new org.jboss.cache.TreeCache();
PropertyConfigurator config = new PropertyConfigurator();
config.configure( cache, resource );
TransactionManagerLookup transactionManagerLookup =
TransactionManagerLookupFactory.getTransactionManagerLookup( properties );
if ( transactionManagerLookup == null ) {
throw new CacheException(
"JBossCache only supports optimisitc locking with a configured " +
"TransactionManagerLookup (" + Environment.TRANSACTION_MANAGER_STRATEGY + ")"
);
}
cache.setTransactionManagerLookup(
new TransactionManagerLookupAdaptor(
transactionManagerLookup,
properties
)
);
if ( ! NODE_LOCKING_SCHEME.equalsIgnoreCase( cache.getNodeLockingScheme() ) ) {
log.info( "Overriding node-locking-scheme to : " + NODE_LOCKING_SCHEME );
cache.setNodeLockingScheme( NODE_LOCKING_SCHEME );
}
cache.start();
}
catch ( Exception e ) {
throw new CacheException( e );
}
}
public void stop() {
if ( cache != null ) {
cache.stop();
cache.destroy();
cache = null;
}
}
public boolean isMinimalPutsEnabledByDefault() {
return true;
}
static final class TransactionManagerLookupAdaptor implements org.jboss.cache.TransactionManagerLookup {
private final TransactionManagerLookup tml;
private final Properties props;
TransactionManagerLookupAdaptor(TransactionManagerLookup tml, Properties props) {
this.tml = tml;
this.props = props;
}
public TransactionManager getTransactionManager() throws Exception {
return tml.getTransactionManager( props );
}
}
public org.jboss.cache.TreeCache getUnderlyingCache() {
return cache;
}
}