/*
* 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.index.fielddata;
import org.apache.lucene.util.ArrayUtil;
import org.apache.lucene.util.InPlaceMergeSorter;
import org.apache.lucene.util.Sorter;
/**
* Base class for building {@link SortedNumericDoubleValues} instances based on unsorted content.
*/
public abstract class SortingNumericDoubleValues extends SortedNumericDoubleValues {
private int count;
private int valuesCursor;
protected double[] values;
private final Sorter sorter;
protected SortingNumericDoubleValues() {
values = new double[1];
valuesCursor = 0;
sorter = new InPlaceMergeSorter() {
@Override
protected void swap(int i, int j) {
final double tmp = values[i];
values[i] = values[j];
values[j] = tmp;
}
@Override
protected int compare(int i, int j) {
return Double.compare(values[i], values[j]);
}
};
}
/**
* Set the {@link #docValueCount()} and ensure that the {@link #values} array can
* store at least that many entries.
*/
protected final void resize(int newSize) {
count = newSize;
values = ArrayUtil.grow(values, count);
valuesCursor = 0;
}
/**
* Sort values that are stored between offsets <code>0</code> and
* {@link #docValueCount} of {@link #values}.
*/
protected final void sort() {
sorter.sort(0, count);
}
@Override
public final int docValueCount() {
return count;
}
@Override
public final double nextValue() {
return values[valuesCursor++];
}
}