/**
Copyright (C) SYSTAP, LLC DBA Blazegraph 2006-2016. All rights reserved.
Contact:
SYSTAP, LLC DBA Blazegraph
2501 Calvert ST NW #106
Washington, DC 20008
licenses@blazegraph.com
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; version 2 of the License.
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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/*
* Created on Sep 28, 2010
*/
package com.bigdata.rdf.lexicon;
import java.util.Map;
import com.bigdata.bop.BOp;
import com.bigdata.bop.ap.filter.BOpResolver;
import com.bigdata.rdf.internal.IV;
import com.bigdata.rdf.model.BigdataValue;
/**
* Cache the {@link BigdataValue} on the {@link IV} (create a cross linkage).
* This is useful for lexicon joins and SPARQL operators that need to use
* materialized RDF values.
*/
public class CacheValueFilter extends BOpResolver {
/**
*
*/
private static final long serialVersionUID = -7267351719878117114L;
/**
* A default instance.
*/
public static CacheValueFilter newInstance() {
return new CacheValueFilter(BOp.NOARGS, BOp.NOANNS);
}
/**
* @param op
*/
public CacheValueFilter(CacheValueFilter op) {
super(op);
}
/**
* @param args
* @param annotations
*/
public CacheValueFilter(BOp[] args, Map<String, Object> annotations) {
super(args, annotations);
}
/**
* Cache the BigdataValue on its IV (cross-link).
*/
@Override
protected Object resolve(final Object obj) {
final BigdataValue val = (BigdataValue) obj;
// the link from BigdataValue to IV is pre-existing (set by the
// materialization of the index tuple)
final IV iv = val.getIV();
// cache the value on the IV
iv.setValue(val);
return obj;
}
}