org.elasticsearch.common.lucene.docset.MatchDocIdSet Maven / Gradle / Ivy
/*
* 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.common.lucene.docset;
import org.apache.lucene.search.DocIdSet;
import org.apache.lucene.search.DocIdSetIterator;
import org.apache.lucene.search.FilteredDocIdSetIterator;
import org.apache.lucene.util.Bits;
import org.apache.lucene.util.FixedBitSet;
import org.elasticsearch.common.Nullable;
import java.io.IOException;
/**
* A {@link DocIdSet} that works on a "doc" level by checking if it matches or not.
*/
public abstract class MatchDocIdSet extends DocIdSet implements Bits {
private final int maxDoc;
private final Bits acceptDocs;
protected MatchDocIdSet(int maxDoc, @Nullable Bits acceptDocs) {
this.maxDoc = maxDoc;
this.acceptDocs = acceptDocs;
}
/**
* Does this document match?
*/
protected abstract boolean matchDoc(int doc);
@Override
public DocIdSetIterator iterator() throws IOException {
if (acceptDocs == null) {
return new NoAcceptDocsIterator(maxDoc);
} else if (acceptDocs instanceof FixedBitSet) {
return new FixedBitSetIterator(((DocIdSet) acceptDocs).iterator());
} else {
return new BothIterator(maxDoc, acceptDocs);
}
}
@Override
public Bits bits() throws IOException {
return this;
}
@Override
public boolean get(int index) {
return matchDoc(index);
}
@Override
public int length() {
return maxDoc;
}
class NoAcceptDocsIterator extends DocIdSetIterator {
private final int maxDoc;
private int doc = -1;
NoAcceptDocsIterator(int maxDoc) {
this.maxDoc = maxDoc;
}
@Override
public int docID() {
return doc;
}
@Override
public int nextDoc() {
do {
doc++;
if (doc >= maxDoc) {
return doc = NO_MORE_DOCS;
}
} while (!matchDoc(doc));
return doc;
}
@Override
public int advance(int target) {
for (doc = target; doc < maxDoc; doc++) {
if (matchDoc(doc)) {
return doc;
}
}
return doc = NO_MORE_DOCS;
}
@Override
public long cost() {
return maxDoc;
}
}
class FixedBitSetIterator extends FilteredDocIdSetIterator {
FixedBitSetIterator(DocIdSetIterator innerIter) {
super(innerIter);
}
@Override
protected boolean match(int doc) {
return matchDoc(doc);
}
}
class BothIterator extends DocIdSetIterator {
private final int maxDoc;
private final Bits acceptDocs;
private int doc = -1;
BothIterator(int maxDoc, Bits acceptDocs) {
this.maxDoc = maxDoc;
this.acceptDocs = acceptDocs;
}
@Override
public int docID() {
return doc;
}
@Override
public int nextDoc() {
do {
doc++;
if (doc >= maxDoc) {
return doc = NO_MORE_DOCS;
}
} while (!(matchDoc(doc) && acceptDocs.get(doc)));
return doc;
}
@Override
public int advance(int target) {
for (doc = target; doc < maxDoc; doc++) {
if (matchDoc(doc) && acceptDocs.get(doc)) {
return doc;
}
}
return doc = NO_MORE_DOCS;
}
@Override
public long cost() {
return maxDoc;
}
}
}