/*
* 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;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import org.optaplanner.core.impl.domain.entity.descriptor.EntityDescriptor;
import org.optaplanner.core.impl.domain.variable.descriptor.GenuineVariableDescriptor;
import org.optaplanner.core.impl.domain.variable.inverserelation.SingletonInverseVariableDemand;
import org.optaplanner.core.impl.domain.variable.inverserelation.SingletonInverseVariableSupply;
import org.optaplanner.core.impl.domain.variable.supply.SupplyManager;
import org.optaplanner.core.impl.heuristic.move.Move;
import org.optaplanner.core.impl.heuristic.selector.common.iterator.AbstractOriginalSwapIterator;
import org.optaplanner.core.impl.heuristic.selector.common.iterator.AbstractRandomSwapIterator;
import org.optaplanner.core.impl.heuristic.selector.entity.EntitySelector;
import org.optaplanner.core.impl.heuristic.selector.move.generic.chained.ChainedSwapMove;
import org.optaplanner.core.impl.solver.scope.DefaultSolverScope;
public class SwapMoveSelector extends GenericMoveSelector {
protected final EntitySelector leftEntitySelector;
protected final EntitySelector rightEntitySelector;
protected final List<GenuineVariableDescriptor> variableDescriptorList;
protected final boolean randomSelection;
protected final boolean anyChained;
protected List<SingletonInverseVariableSupply> inverseVariableSupplyList = null;
public SwapMoveSelector(EntitySelector leftEntitySelector, EntitySelector rightEntitySelector,
List<GenuineVariableDescriptor> variableDescriptorList, boolean randomSelection) {
this.leftEntitySelector = leftEntitySelector;
this.rightEntitySelector = rightEntitySelector;
this.variableDescriptorList = variableDescriptorList;
this.randomSelection = randomSelection;
EntityDescriptor leftEntityDescriptor = leftEntitySelector.getEntityDescriptor();
EntityDescriptor rightEntityDescriptor = rightEntitySelector.getEntityDescriptor();
if (!leftEntityDescriptor.getEntityClass().equals(rightEntityDescriptor.getEntityClass())) {
throw new IllegalStateException("The selector (" + this
+ ") has a leftEntitySelector's entityClass (" + leftEntityDescriptor.getEntityClass()
+ ") which is not equal to the rightEntitySelector's entityClass ("
+ rightEntityDescriptor.getEntityClass() + ").");
}
boolean anyChained = false;
if (variableDescriptorList.isEmpty()) {
throw new IllegalStateException("The selector (" + this
+ ")'s variableDescriptors (" + variableDescriptorList + ") is empty.");
}
for (GenuineVariableDescriptor variableDescriptor : variableDescriptorList) {
if (!variableDescriptor.getEntityDescriptor().getEntityClass().isAssignableFrom(
leftEntityDescriptor.getEntityClass())) {
throw new IllegalStateException("The selector (" + this
+ ") has a variableDescriptor with a entityClass ("
+ variableDescriptor.getEntityDescriptor().getEntityClass()
+ ") which is not equal or a superclass to the leftEntitySelector's entityClass ("
+ leftEntityDescriptor.getEntityClass() + ").");
}
if (variableDescriptor.isChained()) {
anyChained = true;
}
}
this.anyChained = anyChained;
phaseLifecycleSupport.addEventListener(leftEntitySelector);
if (leftEntitySelector != rightEntitySelector) {
phaseLifecycleSupport.addEventListener(rightEntitySelector);
}
}
@Override
public void solvingStarted(DefaultSolverScope solverScope) {
super.solvingStarted(solverScope);
if (anyChained) {
inverseVariableSupplyList = new ArrayList<>(variableDescriptorList.size());
SupplyManager supplyManager = solverScope.getScoreDirector().getSupplyManager();
for (GenuineVariableDescriptor variableDescriptor : variableDescriptorList) {
SingletonInverseVariableSupply inverseVariableSupply;
if (variableDescriptor.isChained()) {
inverseVariableSupply = supplyManager.demand(
new SingletonInverseVariableDemand(variableDescriptor));
} else {
inverseVariableSupply = null;
}
inverseVariableSupplyList.add(inverseVariableSupply);
}
}
}
@Override
public void solvingEnded(DefaultSolverScope solverScope) {
super.solvingEnded(solverScope);
if (anyChained) {
inverseVariableSupplyList = null;
}
}
// ************************************************************************
// Worker methods
// ************************************************************************
@Override
public boolean isCountable() {
return leftEntitySelector.isCountable() && rightEntitySelector.isCountable();
}
@Override
public boolean isNeverEnding() {
return randomSelection || leftEntitySelector.isNeverEnding() || rightEntitySelector.isNeverEnding();
}
@Override
public long getSize() {
return AbstractOriginalSwapIterator.getSize(leftEntitySelector, rightEntitySelector);
}
@Override
public Iterator<Move> iterator() {
if (!randomSelection) {
return new AbstractOriginalSwapIterator<Move, Object>(leftEntitySelector, rightEntitySelector) {
@Override
protected Move newSwapSelection(Object leftSubSelection, Object rightSubSelection) {
return anyChained
? new ChainedSwapMove(variableDescriptorList, inverseVariableSupplyList, leftSubSelection, rightSubSelection)
: new SwapMove(variableDescriptorList, leftSubSelection, rightSubSelection);
}
};
} else {
return new AbstractRandomSwapIterator<Move, Object>(leftEntitySelector, rightEntitySelector) {
@Override
protected Move newSwapSelection(Object leftSubSelection, Object rightSubSelection) {
return anyChained
? new ChainedSwapMove(variableDescriptorList, inverseVariableSupplyList, leftSubSelection, rightSubSelection)
: new SwapMove(variableDescriptorList, leftSubSelection, rightSubSelection);
}
};
}
}
@Override
public String toString() {
return getClass().getSimpleName() + "(" + leftEntitySelector + ", " + rightEntitySelector + ")";
}
}