/*
* Hibernate, Relational Persistence for Idiomatic Java
*
* Copyright (c) 2010, Red Hat, Inc. and/or its affiliates 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, Inc.
*
* 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.search.store.impl;
import java.util.Properties;
import java.io.Serializable;
import org.apache.lucene.document.Document;
import org.hibernate.search.filter.FullTextFilterImplementor;
import org.hibernate.search.indexes.spi.IndexManager;
import org.hibernate.search.store.IndexShardingStrategy;
/**
* This implementation use idInString as the hashKey.
*
* @author Emmanuel Bernard
*/
public class IdHashShardingStrategy implements IndexShardingStrategy {
private IndexManager[] providers;
public void initialize(Properties properties, IndexManager[] providers) {
this.providers = providers;
}
public IndexManager[] getIndexManagersForAllShards() {
return providers;
}
public IndexManager getIndexManagerForAddition(Class<?> entity, Serializable id, String idInString, Document document) {
return providers[ hashKey(idInString) ];
}
public IndexManager[] getIndexManagersForDeletion(Class<?> entity, Serializable id, String idInString) {
if ( idInString == null ) return providers;
return new IndexManager[] { providers[hashKey( idInString )] };
}
public IndexManager[] getIndexManagersForQuery(FullTextFilterImplementor[] fullTextFilters) {
return getIndexManagersForAllShards();
}
private int hashKey(String key) {
// reproduce the hashCode implementation of String as documented in the javadoc
// to be safe cross Java version (in case it changes some day)
int hash = 0;
int length = key.length();
for ( int index = 0; index < length; index++ ) {
hash = 31 * hash + key.charAt( index );
}
return Math.abs( hash % providers.length );
}
}