/**
* Copyright (c) 2013, Institute of Information Systems (Sven Groppe and contributors of LUPOSDATE), University of Luebeck
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification, are permitted provided that the
* following conditions are met:
*
* - Redistributions of source code must retain the above copyright notice, this list of conditions and the following
* disclaimer.
* - Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the
* following disclaimer in the documentation and/or other materials provided with the distribution.
* - Neither the name of the University of Luebeck nor the names of its contributors may be used to endorse or promote
* products derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
* GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package lupos.rif.visitor;
import lupos.datastructures.items.Item;
import lupos.engine.operators.tripleoperator.TriplePattern;
import lupos.rif.IExpression;
import lupos.rif.IRuleVisitor;
import lupos.rif.RIFException;
import lupos.rif.model.Constant;
import lupos.rif.model.Equality;
import lupos.rif.model.External;
import lupos.rif.model.RuleList;
import lupos.rif.model.RuleVariable;
import lupos.rif.model.Uniterm;
import lupos.rif.operator.BooleanIndexScan;
import lupos.rif.operator.PredicateIndexScan;
import lupos.rif.operator.RuleFilter;
import lupos.sparql1_1.operatorgraph.helper.IndexScanCreatorInterface;
public abstract class BaseGraphBuilder implements IRuleVisitor<Object, Object> {
protected final IndexScanCreatorInterface indexScanCreator;
protected PredicateIndexScan predicateIndex;
protected BooleanIndexScan booleanIndex;
public BaseGraphBuilder(final IndexScanCreatorInterface indexScanCreator) {
super();
this.indexScanCreator = indexScanCreator;
}
public Object visit(RuleList obj, Object arg) throws RIFException {
throw new RIFException("Lists should be translated to Triples before processing in Operatorgraph!");
}
protected abstract RuleFilter buildRuleFilter(IExpression expr, Object arg);
public Object visit(Equality obj, Object arg) throws RIFException {
return buildRuleFilter(obj, arg);
}
public Object visit(External obj, Object arg) throws RIFException {
return buildRuleFilter(obj, arg);
}
public Object visit(Constant obj, Object arg) throws RIFException {
return obj.getLiteral();
}
public Object visit(RuleVariable obj, Object arg) throws RIFException {
return obj.getVariable();
}
protected TriplePattern unitermToTriplePattern(Uniterm obj) {
Item subject = (Item) obj.termParams.get(0).accept(this, null);
Item predicate = (Item) obj.termName.accept(this, null);
Item object = (Item) obj.termParams.get(1).accept(this, null);
TriplePattern pattern = new TriplePattern(subject, predicate, object);
return pattern;
}
}