/*
* 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.BytesRef;
import org.apache.lucene.util.BytesRefBuilder;
import org.apache.lucene.util.InPlaceMergeSorter;
import org.apache.lucene.util.RamUsageEstimator;
import org.apache.lucene.util.Sorter;
import java.util.Arrays;
/**
* Base class for building {@link SortedBinaryDocValues} instances based on unsorted content.
*/
public abstract class SortingBinaryDocValues extends SortedBinaryDocValues {
private int index;
protected int count;
protected BytesRefBuilder[] values;
private final Sorter sorter;
protected SortingBinaryDocValues() {
values = new BytesRefBuilder[] { new BytesRefBuilder() };
sorter = new InPlaceMergeSorter() {
@Override
protected void swap(int i, int j) {
ArrayUtil.swap(values, i, j);
}
@Override
protected int compare(int i, int j) {
return values[i].get().compareTo(values[j].get());
}
};
}
/**
* Make sure the {@link #values} array can store at least {@link #count} entries.
*/
protected final void grow() {
if (values.length < count) {
final int oldLen = values.length;
final int newLen = ArrayUtil.oversize(count, RamUsageEstimator.NUM_BYTES_OBJECT_REF);
values = Arrays.copyOf(values, newLen);
for (int i = oldLen; i < newLen; ++i) {
values[i] = new BytesRefBuilder();
}
}
}
/**
* Sort values that are stored between offsets <code>0</code> and
* {@link #count} of {@link #values}.
*/
protected final void sort() {
sorter.sort(0, count);
index = 0;
}
@Override
public int docValueCount() {
return count;
}
@Override
public final BytesRef nextValue() {
assert index < count;
return values[index++].get();
}
}