/*
* Licensed to ElasticSearch and Shay Banon 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.field.function.sort;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.search.FieldComparator;
import org.apache.lucene.search.Scorer;
import org.apache.lucene.search.SortField;
import org.elasticsearch.index.field.data.FieldDataType;
import org.elasticsearch.script.SearchScript;
import java.io.IOException;
/**
*
*/
public class StringFieldsFunctionDataComparator extends FieldComparator {
public static FieldDataType.ExtendedFieldComparatorSource comparatorSource(SearchScript script) {
return new InnerSource(script);
}
private static class InnerSource extends FieldDataType.ExtendedFieldComparatorSource {
private final SearchScript script;
private InnerSource(SearchScript script) {
this.script = script;
}
@Override
public FieldComparator newComparator(String fieldname, int numHits, int sortPos, boolean reversed) throws IOException {
return new StringFieldsFunctionDataComparator(numHits, script);
}
@Override
public int reducedType() {
return SortField.STRING;
}
}
private final SearchScript script;
private String[] values;
private String bottom;
public StringFieldsFunctionDataComparator(int numHits, SearchScript script) {
this.script = script;
values = new String[numHits];
}
@Override
public void setNextReader(IndexReader reader, int docBase) throws IOException {
script.setNextReader(reader);
}
@Override
public void setScorer(Scorer scorer) {
script.setScorer(scorer);
}
@Override
public int compare(int slot1, int slot2) {
final String val1 = values[slot1];
final String val2 = values[slot2];
if (val1 == null) {
if (val2 == null) {
return 0;
}
return -1;
} else if (val2 == null) {
return 1;
}
return val1.compareTo(val2);
}
@Override
public int compareBottom(int doc) {
script.setNextDocId(doc);
final String val2 = script.run().toString();
if (bottom == null) {
if (val2 == null) {
return 0;
}
return -1;
} else if (val2 == null) {
return 1;
}
return bottom.compareTo(val2);
}
@Override
public void copy(int slot, int doc) {
script.setNextDocId(doc);
values[slot] = script.run().toString();
}
@Override
public void setBottom(final int bottom) {
this.bottom = values[bottom];
}
@Override
public Comparable value(int slot) {
return values[slot];
}
}