/*
* Copyright 2011 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.optaplanner.core.impl.score.director.drools;
import java.util.Collection;
import org.kie.api.KieBase;
import org.kie.api.runtime.KieSession;
import org.kie.api.runtime.rule.FactHandle;
import org.optaplanner.core.api.domain.solution.Solution;
import org.optaplanner.core.api.score.Score;
import org.optaplanner.core.api.score.constraint.ConstraintMatchTotal;
import org.optaplanner.core.api.score.holder.ScoreHolder;
import org.optaplanner.core.impl.domain.entity.descriptor.EntityDescriptor;
import org.optaplanner.core.impl.domain.variable.descriptor.VariableDescriptor;
import org.optaplanner.core.impl.score.director.AbstractScoreDirector;
import org.optaplanner.core.impl.score.director.ScoreDirector;
/**
* Drools implementation of {@link ScoreDirector}, which directs the Rule Engine to calculate the {@link Score}
* of the {@link Solution} workingSolution.
* @see ScoreDirector
*/
public class DroolsScoreDirector extends AbstractScoreDirector<DroolsScoreDirectorFactory> {
public static final String GLOBAL_SCORE_HOLDER_KEY = "scoreHolder";
protected KieSession kieSession;
protected ScoreHolder workingScoreHolder;
public DroolsScoreDirector(DroolsScoreDirectorFactory scoreDirectorFactory,
boolean constraintMatchEnabledPreference) {
super(scoreDirectorFactory, constraintMatchEnabledPreference);
}
protected KieBase getKieBase() {
return scoreDirectorFactory.getKieBase();
}
public KieSession getKieSession() {
return kieSession;
}
// ************************************************************************
// Complex methods
// ************************************************************************
@Override
public void setWorkingSolution(Solution workingSolution) {
super.setWorkingSolution(workingSolution);
resetKieSession();
}
private void resetKieSession() {
if (kieSession != null) {
kieSession.dispose();
}
kieSession = getKieBase().newKieSession();
workingScoreHolder = getScoreDefinition().buildScoreHolder(constraintMatchEnabledPreference);
kieSession.setGlobal(GLOBAL_SCORE_HOLDER_KEY, workingScoreHolder);
// TODO Adjust when uninitialized entities from getWorkingFacts get added automatically too (and call afterEntityAdded)
Collection<Object> workingFacts = getWorkingFacts();
for (Object fact : workingFacts) {
kieSession.insert(fact);
}
}
public Collection<Object> getWorkingFacts() {
return getSolutionDescriptor().getAllFacts(workingSolution);
}
public Score calculateScore() {
kieSession.fireAllRules();
Score score = workingScoreHolder.extractScore();
setCalculatedScore(score);
return score;
}
public boolean isConstraintMatchEnabled() {
return workingScoreHolder.isConstraintMatchEnabled();
}
public Collection<ConstraintMatchTotal> getConstraintMatchTotals() {
kieSession.fireAllRules();
return workingScoreHolder.getConstraintMatchTotals();
}
@Override
public DroolsScoreDirector clone() {
// TODO experiment with serializing the KieSession to clone it and its entities but not its other facts.
// See drools-compiler's test SerializationHelper.getSerialisedStatefulKnowledgeSession(...)
// and use an identity FactFactory that:
// - returns the reference for a non-@PlanningEntity fact
// - returns a clone for a @PlanningEntity fact (Pitfall: chained planning entities)
// Note: currently that will break incremental score calculation, but future drools versions might fix that
return (DroolsScoreDirector) super.clone();
}
@Override
public void dispose() {
if (kieSession != null) {
kieSession.dispose();
kieSession = null;
}
}
// ************************************************************************
// Entity/variable add/change/remove methods
// ************************************************************************
// public void beforeEntityAdded(EntityDescriptor entityDescriptor, Object entity) // Do nothing
@Override
public void afterEntityAdded(EntityDescriptor entityDescriptor, Object entity) {
if (entity == null) {
throw new IllegalArgumentException("The entity (" + entity + ") cannot be added to the ScoreDirector.");
}
if (!getSolutionDescriptor().hasEntityDescriptor(entity.getClass())) {
throw new IllegalArgumentException("The entity (" + entity + ") of class (" + entity.getClass()
+ ") is not a configured @PlanningEntity.");
}
if (kieSession.getFactHandle(entity) != null) {
throw new IllegalArgumentException("The entity (" + entity
+ ") was already added to this ScoreDirector."
+ " Usually the cause is that that specific instance was already in your Solution's entities" +
" and you probably want to use before/afterVariableChanged() instead.");
}
kieSession.insert(entity);
super.afterEntityAdded(entityDescriptor, entity);
}
// public void beforeVariableChanged(VariableDescriptor variableDescriptor, Object entity) // Do nothing
@Override
public void afterVariableChanged(VariableDescriptor variableDescriptor, Object entity) {
update(entity);
super.afterVariableChanged(variableDescriptor, entity);
}
private void update(Object entity) {
FactHandle factHandle = kieSession.getFactHandle(entity);
if (factHandle == null) {
throw new IllegalArgumentException("The entity (" + entity
+ ") was never added to this ScoreDirector."
+ " Usually the cause is that that specific instance was not in your Solution's entities.");
}
kieSession.update(factHandle, entity);
}
// public void beforeEntityRemoved(EntityDescriptor entityDescriptor, Object entity) // Do nothing
@Override
public void afterEntityRemoved(EntityDescriptor entityDescriptor, Object entity) {
FactHandle factHandle = kieSession.getFactHandle(entity);
if (factHandle == null) {
throw new IllegalArgumentException("The entity (" + entity
+ ") was never added to this ScoreDirector."
+ " Usually the cause is that that specific instance was not in your Solution's entities.");
}
kieSession.delete(factHandle);
super.afterEntityRemoved(entityDescriptor, entity);
}
// ************************************************************************
// Problem fact add/change/remove methods
// ************************************************************************
// public void beforeProblemFactAdded(Object problemFact) // Do nothing
@Override
public void afterProblemFactAdded(Object problemFact) {
if (kieSession.getFactHandle(problemFact) != null) {
throw new IllegalArgumentException("The problemFact (" + problemFact
+ ") was already added to this ScoreDirector."
+ " Usually the cause is that that specific instance was already in your Solution's getProblemFacts()"
+ " and you probably want to use before/afterProblemFactChanged() instead.");
}
kieSession.insert(problemFact);
super.afterProblemFactAdded(problemFact);
}
// public void beforeProblemFactChanged(Object problemFact) // Do nothing
@Override
public void afterProblemFactChanged(Object problemFact) {
FactHandle factHandle = kieSession.getFactHandle(problemFact);
if (factHandle == null) {
throw new IllegalArgumentException("The problemFact (" + problemFact
+ ") was never added to this ScoreDirector."
+ " Usually the cause is that that specific instance was not in your Solution's getProblemFacts().");
}
kieSession.update(factHandle, problemFact);
super.afterProblemFactChanged(problemFact);
}
// public void beforeProblemFactRemoved(Object problemFact) // Do nothing
@Override
public void afterProblemFactRemoved(Object problemFact) {
FactHandle factHandle = kieSession.getFactHandle(problemFact);
if (factHandle == null) {
throw new IllegalArgumentException("The problemFact (" + problemFact
+ ") was never added to this ScoreDirector."
+ " Usually the cause is that that specific instance was not in your Solution's getProblemFacts().");
}
kieSession.delete(factHandle);
super.afterProblemFactRemoved(problemFact);
}
}