/*
* This file is part of the Heritrix web crawler (crawler.archive.org).
*
* Licensed to the Internet Archive (IA) by one or more individual
* contributors.
*
* The IA licenses this file to You 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 org.archive.bdb;
import java.lang.ref.WeakReference;
import com.esotericsoftware.kryo.Kryo;
import com.esotericsoftware.kryo.ObjectBuffer;
import com.sleepycat.bind.EntryBinding;
import com.sleepycat.je.DatabaseEntry;
/**
* Binding for use with BerkeleyDB-JE that uses Kryo serialization rather
* than BDB's (custom version of) Java serialization.
*
* @contributor gojomo
*/
public class KryoBinding<K> implements EntryBinding<K> {
protected Class<K> baseClass;
protected AutoKryo kryo = new AutoKryo();
protected ThreadLocal<WeakReference<ObjectBuffer>> threadBuffer = new ThreadLocal<WeakReference<ObjectBuffer>>() {
@Override
protected WeakReference<ObjectBuffer> initialValue() {
return new WeakReference<ObjectBuffer>(new ObjectBuffer(kryo,16*1024,Integer.MAX_VALUE));
}
};
/**
* Constructor. Save parameters locally, as superclass
* fields are private.
*
* @param classCatalog is the catalog to hold shared class information
*
* @param baseClass is the base class for serialized objects stored using
* this binding
*/
public KryoBinding(Class<K> baseClass) {
this.baseClass = baseClass;
kryo.autoregister(baseClass);
// TODO: reevaluate if explicit registration should be required
kryo.setRegistrationOptional(true);
}
public Kryo getKryo() {
return kryo;
}
private ObjectBuffer getBuffer() {
WeakReference<ObjectBuffer> ref = threadBuffer.get();
ObjectBuffer ob = ref.get();
if (ob == null) {
ob = new ObjectBuffer(kryo,16*1024,Integer.MAX_VALUE);
threadBuffer.set(new WeakReference<ObjectBuffer>(ob));
}
return ob;
}
/**
* Copies superclass simply to allow different source for FastOoutputStream.
*
* @see com.sleepycat.bind.serial.SerialBinding#entryToObject
*/
public void objectToEntry(K object, DatabaseEntry entry) {
entry.setData(getBuffer().writeObjectData(object));
}
@Override
public K entryToObject(DatabaseEntry entry) {
return getBuffer().readObjectData(entry.getData(), baseClass);
}
}