/*
* Copyright 2013 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.domain.variable.inverserelation;
import org.optaplanner.core.impl.domain.variable.descriptor.VariableDescriptor;
import org.optaplanner.core.impl.domain.variable.listener.VariableListener;
import org.optaplanner.core.impl.score.director.ScoreDirector;
public class SingletonInverseVariableListener implements VariableListener<Object>, SingletonInverseVariableSupply {
protected final InverseRelationShadowVariableDescriptor shadowVariableDescriptor;
protected final VariableDescriptor sourceVariableDescriptor;
public SingletonInverseVariableListener(InverseRelationShadowVariableDescriptor shadowVariableDescriptor,
VariableDescriptor sourceVariableDescriptor) {
this.shadowVariableDescriptor = shadowVariableDescriptor;
this.sourceVariableDescriptor = sourceVariableDescriptor;
}
@Override
public void beforeEntityAdded(ScoreDirector scoreDirector, Object entity) {
// Do nothing
}
@Override
public void afterEntityAdded(ScoreDirector scoreDirector, Object entity) {
insert(scoreDirector, entity);
}
@Override
public void beforeVariableChanged(ScoreDirector scoreDirector, Object entity) {
retract(scoreDirector, entity);
}
@Override
public void afterVariableChanged(ScoreDirector scoreDirector, Object entity) {
insert(scoreDirector, entity);
}
@Override
public void beforeEntityRemoved(ScoreDirector scoreDirector, Object entity) {
retract(scoreDirector, entity);
}
@Override
public void afterEntityRemoved(ScoreDirector scoreDirector, Object entity) {
// Do nothing
}
protected void insert(ScoreDirector scoreDirector, Object entity) {
Object shadowEntity = sourceVariableDescriptor.getValue(entity);
if (shadowEntity != null) {
Object shadowValue = shadowVariableDescriptor.getValue(shadowEntity);
if (shadowValue != null) {
throw new IllegalStateException("The entity (" + entity
+ ") has a variable (" + sourceVariableDescriptor.getVariableName()
+ ") with value (" + shadowEntity
+ ") which has a sourceVariableName variable (" + shadowVariableDescriptor.getVariableName()
+ ") with a value (" + shadowValue + ") which is not null.\n"
+ "Verify the consistency of your input problem for that sourceVariableName variable.");
}
scoreDirector.beforeVariableChanged(shadowVariableDescriptor, shadowEntity);
shadowVariableDescriptor.setValue(shadowEntity, entity);
scoreDirector.afterVariableChanged(shadowVariableDescriptor, shadowEntity);
}
}
protected void retract(ScoreDirector scoreDirector, Object entity) {
Object shadowEntity = sourceVariableDescriptor.getValue(entity);
if (shadowEntity != null) {
Object shadowValue = shadowVariableDescriptor.getValue(shadowEntity);
if (shadowValue != entity) {
throw new IllegalStateException("The entity (" + entity
+ ") has a variable (" + sourceVariableDescriptor.getVariableName()
+ ") with value (" + shadowEntity
+ ") which has a sourceVariableName variable (" + shadowVariableDescriptor.getVariableName()
+ ") with a value (" + shadowValue + ") which is not that entity.\n"
+ "Verify the consistency of your input problem for that sourceVariableName variable.");
}
scoreDirector.beforeVariableChanged(shadowVariableDescriptor, shadowEntity);
shadowVariableDescriptor.setValue(shadowEntity, null);
scoreDirector.afterVariableChanged(shadowVariableDescriptor, shadowEntity);
}
}
@Override
public Object getInverseSingleton(Object planningValue) {
return shadowVariableDescriptor.getValue(planningValue);
}
}