/*
* Copyright 2015 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.common.iterator;
import java.util.Collections;
import java.util.Iterator;
import org.optaplanner.core.impl.heuristic.move.Move;
import org.optaplanner.core.impl.heuristic.selector.entity.EntitySelector;
import org.optaplanner.core.impl.heuristic.selector.value.ValueSelector;
public abstract class AbstractOriginalChangeIterator<S extends Move> extends UpcomingSelectionIterator<S> {
private final EntitySelector entitySelector;
private final ValueSelector valueSelector;
private Iterator<Object> entityIterator;
private Iterator<Object> valueIterator;
private Object upcomingEntity;
public AbstractOriginalChangeIterator(EntitySelector entitySelector, ValueSelector valueSelector) {
this.entitySelector = entitySelector;
this.valueSelector = valueSelector;
entityIterator = entitySelector.iterator();
// Don't do hasNext() in constructor (to avoid upcoming selections breaking mimic recording)
valueIterator = Collections.emptyIterator();
}
@Override
protected S createUpcomingSelection() {
while (!valueIterator.hasNext()) {
if (!entityIterator.hasNext()) {
return noUpcomingSelection();
}
upcomingEntity = entityIterator.next();
valueIterator = valueSelector.iterator(upcomingEntity);
}
Object toValue = valueIterator.next();
return newChangeSelection(upcomingEntity, toValue);
}
protected abstract S newChangeSelection(Object entity, Object toValue);
}