org.elasticsearch.search.aggregations.bucket.DocCountProvider Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of elasticsearch Show documentation
Show all versions of elasticsearch Show documentation
Elasticsearch subproject :server
/*
* Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
* or more contributor license agreements. Licensed under the Elastic License
* 2.0 and the Server Side Public License, v 1; you may not use this file except
* in compliance with, at your election, the Elastic License 2.0 or the Server
* Side Public License, v 1.
*/
package org.elasticsearch.search.aggregations.bucket;
import org.apache.lucene.index.LeafReaderContext;
import org.apache.lucene.index.PostingsEnum;
import org.apache.lucene.index.Term;
import org.elasticsearch.index.mapper.DocCountFieldMapper;
import java.io.IOException;
/**
* An implementation of a doc_count provider that reads the value
* of the _doc_count field in the document. If a document does not have a
* _doc_count field the implementation will return 1 as the default value.
*/
public class DocCountProvider {
public static final int DEFAULT_VALUE = DocCountFieldMapper.DocCountFieldType.DEFAULT_VALUE;
private PostingsEnum docCountPostings;
public int getDocCount(int doc) throws IOException {
if (docCountPostings == null) {
return DEFAULT_VALUE;
}
if (docCountPostings.docID() < doc) {
docCountPostings.advance(doc);
}
if (docCountPostings.docID() == doc) {
return docCountPostings.freq();
} else {
return DEFAULT_VALUE;
}
}
public void setLeafReaderContext(LeafReaderContext ctx) throws IOException {
docCountPostings = ctx.reader().postings(new Term(DocCountFieldMapper.NAME, DocCountFieldMapper.NAME));
}
public boolean alwaysOne() {
return docCountPostings == null;
}
@Override
public String toString() {
return "doc counts are " + (alwaysOne() ? "always one" : "based on " + docCountPostings);
}
}