/*
* Copyright 2010 JBoss Inc
*
* 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.drools.planner.core.localsearch.decider.selector;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Random;
import org.drools.planner.core.localsearch.LocalSearchSolverScope;
import org.drools.planner.core.localsearch.LocalSearchStepScope;
import org.drools.planner.core.localsearch.decider.Decider;
import org.drools.planner.core.move.Move;
/**
* A CompositeSelector unions multiple Selectors.
*/
public class CompositeSelector extends AbstractSelector {
protected List<Selector> selectorList;
public void setSelectorList(List<Selector> selectorList) {
this.selectorList = selectorList;
}
@Override
public void setDecider(Decider decider) {
super.setDecider(decider);
for (Selector selector : selectorList) {
selector.setDecider(decider);
}
}
// ************************************************************************
// Worker methods
// ************************************************************************
@Override
public void solvingStarted(LocalSearchSolverScope localSearchSolverScope) {
for (Selector selector : selectorList) {
selector.solvingStarted(localSearchSolverScope);
}
}
@Override
public void beforeDeciding(LocalSearchStepScope localSearchStepScope) {
for (Selector selector : selectorList) {
selector.beforeDeciding(localSearchStepScope);
}
}
public Iterator<Move> moveIterator(LocalSearchStepScope localSearchStepScope) {
List<Iterator<Move>> moveIteratorList = new ArrayList<Iterator<Move>>(selectorList.size());
// TODO unoptimized code: use Selector.moveList(localSearchStepScope) instead
for (Selector selector : selectorList) {
Iterator<Move> moveIterator = selector.moveIterator(localSearchStepScope);
if (moveIterator.hasNext()) {
moveIteratorList.add(moveIterator);
}
}
return new CompositeSelectorMoveIterator(localSearchStepScope.getWorkingRandom(), moveIteratorList);
}
@Override
public void stepDecided(LocalSearchStepScope localSearchStepScope) {
for (Selector selector : selectorList) {
selector.stepDecided(localSearchStepScope);
}
}
@Override
public void stepTaken(LocalSearchStepScope localSearchStepScope) {
for (Selector selector : selectorList) {
selector.stepTaken(localSearchStepScope);
}
}
@Override
public void solvingEnded(LocalSearchSolverScope localSearchSolverScope) {
for (Selector selector : selectorList) {
selector.solvingEnded(localSearchSolverScope);
}
}
private static class CompositeSelectorMoveIterator implements Iterator<Move> {
private final List<Iterator<Move>> moveIteratorList;
private final Random workingRandom;
public CompositeSelectorMoveIterator(Random workingRandom, List<Iterator<Move>> moveIteratorList) {
this.moveIteratorList = moveIteratorList;
this.workingRandom = workingRandom;
}
public boolean hasNext() {
return !moveIteratorList.isEmpty();
}
public Move next() {
int moveIteratorIndex = workingRandom.nextInt(moveIteratorList.size());
Iterator<Move> moveIterator = moveIteratorList.get(moveIteratorIndex);
Move next = moveIterator.next();
if (!moveIterator.hasNext()) {
moveIteratorList.remove(moveIteratorIndex);
}
return next;
}
public void remove() {
throw new UnsupportedOperationException(
"The remove method is not supported on CompositeSelectorMoveIterator");
}
}
}