/*
* Copyright Aduna (http://www.aduna-software.com/) (c) 2008.
*
* Licensed under the Aduna BSD-style license.
*/
package org.openrdf.sail.rdbms.optimizers;
import org.openrdf.query.BindingSet;
import org.openrdf.query.Dataset;
import org.openrdf.query.algebra.TupleExpr;
import org.openrdf.query.algebra.Var;
import org.openrdf.query.algebra.evaluation.QueryOptimizer;
import org.openrdf.query.algebra.helpers.QueryModelVisitorBase;
import org.openrdf.sail.rdbms.RdbmsValueFactory;
/**
* Iterates through the query and converting the values into RDBMS values.
*
* @author James Leigh
*
*/
public class ValueIdLookupOptimizer implements QueryOptimizer {
RdbmsValueFactory vf;
public ValueIdLookupOptimizer(RdbmsValueFactory vf) {
super();
this.vf = vf;
}
public void optimize(TupleExpr tupleExpr, Dataset dataset,
BindingSet bindings) {
tupleExpr.visit(new VarVisitor());
}
protected class VarVisitor extends QueryModelVisitorBase<RuntimeException> {
@Override
public void meet(Var var) {
if (var.hasValue()) {
var.setValue(vf.asRdbmsValue(var.getValue()));
}
}
}
}
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