/*
* Copyright 2008-2009 LinkedIn, Inc
*
* 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 voldemort.store.memory;
import java.util.List;
import java.util.concurrent.ConcurrentMap;
import voldemort.VoldemortException;
import voldemort.routing.RoutingStrategy;
import voldemort.server.VoldemortConfig;
import voldemort.store.StorageConfiguration;
import voldemort.store.StorageEngine;
import voldemort.store.StoreDefinition;
import voldemort.utils.ByteArray;
import voldemort.versioning.Versioned;
import com.google.common.collect.MapMaker;
/**
* Identical to the InMemoryStorageConfiguration except that it creates google
* collections ReferenceMap with Soft references on both keys and values. This
* behaves like a cache, discarding values when under memory pressure.
*
*
*/
public class CacheStorageConfiguration implements StorageConfiguration {
public static final String TYPE_NAME = "cache";
public CacheStorageConfiguration() {}
@SuppressWarnings("unused")
public CacheStorageConfiguration(VoldemortConfig config) {}
public void close() {}
public StorageEngine<ByteArray, byte[], byte[]> getStore(StoreDefinition storeDef,
RoutingStrategy strategy) {
ConcurrentMap<ByteArray, List<Versioned<byte[]>>> backingMap = new MapMaker().softValues()
.makeMap();
return new InMemoryStorageEngine<ByteArray, byte[], byte[]>(storeDef.getName(), backingMap);
}
public String getType() {
return TYPE_NAME;
}
public void update(StoreDefinition storeDef) {
throw new VoldemortException("Storage config updates not permitted for " + this.getType()
+ " storage engine");
}
// Nothing to do here: we're not tracking the created storage engine.
@Override
public void removeStorageEngine(StorageEngine<ByteArray, byte[], byte[]> engine) {}
}