/*
* Copyright 2012 Red Hat, Inc. and/or its affiliates.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.optaplanner.core.impl.heuristic.selector.move.generic.chained;
import java.util.Objects;
import org.optaplanner.core.api.domain.solution.PlanningSolution;
import org.optaplanner.core.impl.domain.variable.descriptor.GenuineVariableDescriptor;
import org.optaplanner.core.impl.domain.variable.inverserelation.SingletonInverseVariableSupply;
import org.optaplanner.core.impl.heuristic.selector.move.generic.ChangeMove;
import org.optaplanner.core.impl.score.director.ScoreDirector;
/**
* @param <Solution_> the solution type, the class with the {@link PlanningSolution} annotation
*/
public class ChainedChangeMove<Solution_> extends ChangeMove<Solution_> {
protected final SingletonInverseVariableSupply inverseVariableSupply;
public ChainedChangeMove(Object entity, GenuineVariableDescriptor<Solution_> variableDescriptor,
SingletonInverseVariableSupply inverseVariableSupply, Object toPlanningValue) {
super(entity, variableDescriptor, toPlanningValue);
this.inverseVariableSupply = inverseVariableSupply;
}
// ************************************************************************
// Worker methods
// ************************************************************************
@Override
public boolean isMoveDoable(ScoreDirector<Solution_> scoreDirector) {
return super.isMoveDoable(scoreDirector)
&& !Objects.equals(entity, toPlanningValue);
}
@Override
public ChainedChangeMove<Solution_> createUndoMove(ScoreDirector<Solution_> scoreDirector) {
Object oldValue = variableDescriptor.getValue(entity);
return new ChainedChangeMove<>(entity, variableDescriptor, inverseVariableSupply, oldValue);
}
@Override
protected void doMoveOnGenuineVariables(ScoreDirector<Solution_> scoreDirector) {
Object oldValue = variableDescriptor.getValue(entity);
Object oldTrailingEntity = inverseVariableSupply.getInverseSingleton(entity);
Object newTrailingEntity = toPlanningValue == null ? null
: inverseVariableSupply.getInverseSingleton(toPlanningValue);
// Close the old chain
if (oldTrailingEntity != null) {
scoreDirector.changeVariableFacade(variableDescriptor, oldTrailingEntity, oldValue);
}
// Change the entity
scoreDirector.changeVariableFacade(variableDescriptor, entity, toPlanningValue);
// Reroute the new chain
if (newTrailingEntity != null) {
scoreDirector.changeVariableFacade(variableDescriptor, newTrailingEntity, entity);
}
}
}