/**
* 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.optimizations.logical.rules.rdfs;
import java.util.Collection;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.Map;
import lupos.datastructures.items.Variable;
import lupos.engine.operators.BasicOperator;
import lupos.engine.operators.OperatorIDTuple;
import lupos.engine.operators.messages.BoundVariablesMessage;
import lupos.engine.operators.multiinput.optional.Optional;
import lupos.engine.operators.singleinput.generate.GenerateAddEnv;
import lupos.misc.Tuple;
import lupos.optimizations.logical.rules.Rule;
public class RuleGenerateAddOverOptional extends Rule {
@Override
protected void init() {
final GenerateAddEnv genAdd = new GenerateAddEnv();
final Optional optional = new Optional();
// Only left Operand
genAdd.setSucceedingOperator(new OperatorIDTuple(optional, 0));
optional.setPrecedingOperator(genAdd);
subGraphMap = new HashMap<BasicOperator, String>();
subGraphMap.put(genAdd, "genAdd");
subGraphMap.put(optional, "optional");
startNode = genAdd;
}
@Override
protected boolean checkPrecondition(final Map<String, BasicOperator> mso) {
final Optional optional = (Optional) mso.get("optional");
final GenerateAddEnv genAdd = (GenerateAddEnv) mso.get("genAdd");
final Object[] optionalVars = optional.getIntersectionVariables()
.toArray();
final Object[] v = genAdd.getConstants().keySet().toArray();
// All Tuples should not have a join-partner of the Optional on the left
// side
for (int i = 0; i < v.length; i++) {
if (arrayContains(optionalVars, (Variable) v[i])) {
return false;
}
}
// Operator should be the left operand of optional
return (genAdd.getOperatorIDTuple(optional).getId() == 0);
}
@Override
public Tuple<Collection<BasicOperator>, Collection<BasicOperator>> transformOperatorGraph(
final Map<String, BasicOperator> mso,
final BasicOperator rootOperator) {
final GenerateAddEnv genAdd = (GenerateAddEnv) mso.get("genAdd");
final Optional optional = (Optional) mso.get("optional");
final LinkedList<BasicOperator> pres = (LinkedList<BasicOperator>) genAdd
.getPrecedingOperators();
final LinkedList<OperatorIDTuple> succs = (LinkedList<OperatorIDTuple>) optional
.getSucceedingOperators();
BasicOperator pre;
for (int i = 0; i < pres.size(); i++) {
pre = pres.get(i);
pre.addSucceedingOperator(new OperatorIDTuple(optional, 0));
pre.removeSucceedingOperator(genAdd);
optional.addPrecedingOperator(pre);
}
optional.removePrecedingOperator(genAdd);
optional.setSucceedingOperator(new OperatorIDTuple(genAdd, 0));
genAdd.setPrecedingOperator(optional);
genAdd.setSucceedingOperators(succs);
BasicOperator succ;
for (int i = 0; i < succs.size(); i++) {
succ = succs.get(i).getOperator();
succ.addPrecedingOperator(genAdd);
succ.removePrecedingOperator(optional);
}
rootOperator.deleteParents();
rootOperator.setParents();
rootOperator.detectCycles();
rootOperator.sendMessage(new BoundVariablesMessage());
return null;
}
private boolean arrayContains(final Object[] vars, final Variable var) {
for (int i = 0; i < vars.length; i++) {
System.out.println(vars[i].toString() + "," + var.toString());
if (vars[i].equals(var))
return true;
}
return false;
}
}