org.elasticsearch.search.sort.MinAndMax Maven / Gradle / Ivy
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* Licensed to Elasticsearch under one or more contributor
* license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright
* ownership. Elasticsearch licenses this file to you 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.elasticsearch.search.sort;
import org.elasticsearch.common.io.stream.StreamInput;
import org.elasticsearch.common.io.stream.StreamOutput;
import org.elasticsearch.common.io.stream.Writeable;
import org.elasticsearch.common.lucene.Lucene;
import java.io.IOException;
import java.util.Comparator;
import java.util.Objects;
/**
* A class that encapsulates a minimum and a maximum {@link Comparable}.
*/
public class MinAndMax> implements Writeable {
private final T minValue;
private final T maxValue;
private MinAndMax(T minValue, T maxValue) {
this.minValue = Objects.requireNonNull(minValue);
this.maxValue = Objects.requireNonNull(maxValue);
}
public MinAndMax(StreamInput in) throws IOException {
this.minValue = (T) Lucene.readSortValue(in);
this.maxValue = (T) Lucene.readSortValue(in);
}
@Override
public void writeTo(StreamOutput out) throws IOException {
Lucene.writeSortValue(out, minValue);
Lucene.writeSortValue(out, maxValue);
}
/**
* Return the minimum value.
*/
public T getMin() {
return minValue;
}
/**
* Return the maximum value.
*/
public T getMax() {
return maxValue;
}
public static > MinAndMax newMinMax(T min, T max) {
return new MinAndMax<>(min, max);
}
/**
* Return a {@link Comparator} for {@link MinAndMax} values according to the provided {@link SortOrder}.
*/
public static Comparator> getComparator(SortOrder order) {
Comparator cmp = order == SortOrder.ASC ?
Comparator.comparing(v -> (Comparable) v.getMin()) : Comparator.comparing(v -> (Comparable) v.getMax());
if (order == SortOrder.DESC) {
cmp = cmp.reversed();
}
return Comparator.nullsLast(cmp);
}
}