/*
* Copyright 2014 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.api.domain.valuerange;
import java.util.Iterator;
import org.optaplanner.core.api.domain.variable.PlanningVariable;
import org.optaplanner.core.impl.domain.valuerange.AbstractCountableValueRange;
/**
* A {@link ValueRange} that is ending. Therefore, it has a discrete (as in non-continuous) range.
* <p>
* An implementation must extend {@link AbstractCountableValueRange}
* to ensure backwards compatibility in future versions.
* @see ValueRangeFactory
* @see ValueRange
* @see AbstractCountableValueRange
*/
public interface CountableValueRange<T> extends ValueRange<T> {
/**
* Used by uniform random selection in a composite or nullable CountableValueRange.
* @return the exact number of elements generated by this {@link CountableValueRange}, always {@code >= 0}
*/
long getSize();
/**
* Used by uniform random selection in a composite or nullable CountableValueRange.
* @param index always {@code <} {@link #getSize()}
* @return sometimes null (if {@link PlanningVariable#nullable()} is true)
*/
T get(long index);
/**
* Select the elements in original (natural) order.
* @return never null
*/
Iterator<T> createOriginalIterator();
}