org.elasticsearch.common.lucene.search.LimitFilter Maven / Gradle / Ivy
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* Licensed to ElasticSearch and Shay Banon under one
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* 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
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package org.elasticsearch.common.lucene.search;
import org.apache.lucene.index.AtomicReaderContext;
import org.apache.lucene.search.DocIdSet;
import org.apache.lucene.util.Bits;
import org.elasticsearch.common.Nullable;
import org.elasticsearch.common.lucene.docset.MatchDocIdSet;
import java.io.IOException;
public class LimitFilter extends NoCacheFilter {
private final int limit;
private int counter;
public LimitFilter(int limit) {
this.limit = limit;
}
public int getLimit() {
return limit;
}
@Override
public DocIdSet getDocIdSet(AtomicReaderContext context, Bits acceptDocs) throws IOException {
if (counter > limit) {
return null;
}
return new LimitDocIdSet(context.reader().maxDoc(), acceptDocs, limit);
}
public class LimitDocIdSet extends MatchDocIdSet {
private final int limit;
public LimitDocIdSet(int maxDoc, @Nullable Bits acceptDocs, int limit) {
super(maxDoc, acceptDocs);
this.limit = limit;
}
@Override
protected boolean matchDoc(int doc) {
if (++counter > limit) {
return false;
}
return true;
}
}
}