/*
* 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;
import java.util.Iterator;
import org.drools.planner.core.localsearch.LocalSearchSolverPhase;
import org.drools.planner.core.localsearch.LocalSearchSolverPhaseScope;
import org.drools.planner.core.localsearch.LocalSearchStepScope;
import org.drools.planner.core.localsearch.decider.acceptor.Acceptor;
import org.drools.planner.core.localsearch.decider.forager.Forager;
import org.drools.planner.core.localsearch.decider.selector.Selector;
import org.drools.planner.core.move.Move;
import org.drools.planner.core.score.Score;
import org.drools.planner.core.score.director.ScoreDirector;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Default implementation of {@link Decider}.
*/
public class DefaultDecider implements Decider {
protected final transient Logger logger = LoggerFactory.getLogger(getClass());
protected LocalSearchSolverPhase localSearchSolverPhase;
protected Selector selector;
protected Acceptor acceptor;
protected Forager forager;
protected boolean assertMoveScoreIsUncorrupted = false;
protected boolean assertUndoMoveIsUncorrupted = false;
public void setLocalSearchSolverPhase(LocalSearchSolverPhase localSearchSolverPhase) {
this.localSearchSolverPhase = localSearchSolverPhase;
}
public void setSelector(Selector selector) {
this.selector = selector;
selector.setDecider(this);
}
public void setAcceptor(Acceptor acceptor) {
this.acceptor = acceptor;
}
public Forager getForager() {
return forager;
}
public void setForager(Forager forager) {
this.forager = forager;
}
public void setAssertMoveScoreIsUncorrupted(boolean assertMoveScoreIsUncorrupted) {
this.assertMoveScoreIsUncorrupted = assertMoveScoreIsUncorrupted;
}
public void setAssertUndoMoveIsUncorrupted(boolean assertUndoMoveIsUncorrupted) {
this.assertUndoMoveIsUncorrupted = assertUndoMoveIsUncorrupted;
}
// ************************************************************************
// Worker methods
// ************************************************************************
public void phaseStarted(LocalSearchSolverPhaseScope localSearchSolverPhaseScope) {
selector.phaseStarted(localSearchSolverPhaseScope);
acceptor.phaseStarted(localSearchSolverPhaseScope);
forager.phaseStarted(localSearchSolverPhaseScope);
}
public void beforeDeciding(LocalSearchStepScope localSearchStepScope) {
selector.beforeDeciding(localSearchStepScope);
acceptor.beforeDeciding(localSearchStepScope);
forager.beforeDeciding(localSearchStepScope);
}
public void decideNextStep(LocalSearchStepScope stepScope) {
ScoreDirector scoreDirector = stepScope.getScoreDirector();
Iterator<Move> moveIterator = selector.moveIterator(stepScope);
while (moveIterator.hasNext()) {
Move move = moveIterator.next();
MoveScope moveScope = new MoveScope(stepScope);
moveScope.setMove(move);
// Filter out not doable moves
if (move.isMoveDoable(scoreDirector)) {
doMove(moveScope);
if (forager.isQuitEarly()) {
break;
}
} else {
logger.trace(" Ignoring not doable move ({}).", move);
}
}
MoveScope pickedMoveScope = forager.pickMove(stepScope);
if (pickedMoveScope != null) {
Move step = pickedMoveScope.getMove();
stepScope.setStep(step);
if (logger.isDebugEnabled()) {
stepScope.setStepString(step.toString());
}
stepScope.setUndoStep(pickedMoveScope.getUndoMove());
stepScope.setScore(pickedMoveScope.getScore());
}
}
private void doMove(MoveScope moveScope) {
ScoreDirector scoreDirector = moveScope.getScoreDirector();
Move move = moveScope.getMove();
Move undoMove = move.createUndoMove(scoreDirector);
moveScope.setUndoMove(undoMove);
move.doMove(scoreDirector);
processMove(moveScope);
undoMove.doMove(scoreDirector);
if (assertUndoMoveIsUncorrupted) {
LocalSearchSolverPhaseScope localSearchSolverPhaseScope = moveScope.getLocalSearchStepScope()
.getLocalSearchSolverPhaseScope();
Score undoScore = localSearchSolverPhaseScope.calculateScore();
Score lastCompletedStepScore = localSearchSolverPhaseScope.getLastCompletedStepScope().getScore();
if (!undoScore.equals(lastCompletedStepScore)) {
// First assert that are probably no corrupted score rules.
scoreDirector.assertWorkingScore(undoScore);
throw new IllegalStateException(
"The moveClass (" + move.getClass() + ")'s move (" + move
+ ") probably has a corrupted undoMove (" + undoMove + ")." +
" Or maybe there are corrupted score rules.\n"
+ "Check the Move.createUndoMove(...) method of that Move class" +
" and enable EnvironmentMode TRACE to fail-faster on corrupted score rules.\n"
+ "Score corruption: the lastCompletedStepScore (" + lastCompletedStepScore
+ ") is not the undoScore (" + undoScore + ").");
}
}
logger.trace(" Move score ({}), accepted ({}) for move ({}).",
new Object[]{moveScope.getScore(), moveScope.getAccepted(), moveScope.getMove()});
}
private void processMove(MoveScope moveScope) {
Score score = moveScope.getLocalSearchStepScope().getLocalSearchSolverPhaseScope().calculateScore();
if (assertMoveScoreIsUncorrupted) {
moveScope.getLocalSearchStepScope().getLocalSearchSolverPhaseScope().assertWorkingScore(score);
}
moveScope.setScore(score);
boolean accepted = acceptor.isAccepted(moveScope);
moveScope.setAccepted(accepted);
forager.addMove(moveScope);
}
public void stepTaken(LocalSearchStepScope localSearchStepScope) {
selector.stepTaken(localSearchStepScope);
acceptor.stepTaken(localSearchStepScope);
forager.stepTaken(localSearchStepScope);
}
public void phaseEnded(LocalSearchSolverPhaseScope localSearchSolverPhaseScope) {
selector.phaseEnded(localSearchSolverPhaseScope);
acceptor.phaseEnded(localSearchSolverPhaseScope);
forager.phaseEnded(localSearchSolverPhaseScope);
}
}