/*
* Licensed to Elastic Search and Shay Banon under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. Elastic Search 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 java.io.IOException;
import java.util.List;
/**
* @author kimchy (shay.banon)
*/
public class AndDocSet extends DocSet {
private final List<DocSet> sets;
public AndDocSet(List<DocSet> sets) {
this.sets = sets;
}
@Override public boolean get(int doc) throws IOException {
for (DocSet s : sets) {
if (!s.get(doc)) return false;
}
return true;
}
@Override public boolean isCacheable() {
// not cacheable, the reason is that by default, when constructing the filter, it is not cacheable,
// so if someone wants it to be cacheable, we might as well construct a cached version of the result
return false;
// for (DocSet set : sets) {
// if (!set.isCacheable()) {
// return false;
// }
// }
// return true;
}
@Override public long sizeInBytes() {
long sizeInBytes = 0;
for (DocSet set : sets) {
sizeInBytes += set.sizeInBytes();
}
return sizeInBytes;
}
@Override public DocIdSetIterator iterator() throws IOException {
return new AndDocIdSetIterator();
}
class AndDocIdSetIterator extends DocIdSetIterator {
int lastReturn = -1;
private DocIdSetIterator[] iterators = null;
AndDocIdSetIterator() throws IOException {
iterators = new DocIdSetIterator[sets.size()];
int j = 0;
for (DocIdSet set : sets) {
if (set == null) {
lastReturn = DocIdSetIterator.NO_MORE_DOCS; // non matching
break;
} else {
DocIdSetIterator dcit = set.iterator();
if (dcit == null) {
lastReturn = DocIdSetIterator.NO_MORE_DOCS; // non matching
break;
}
iterators[j++] = dcit;
}
}
if (lastReturn != DocIdSetIterator.NO_MORE_DOCS) {
lastReturn = (iterators.length > 0 ? -1 : DocIdSetIterator.NO_MORE_DOCS);
}
}
@Override
public final int docID() {
return lastReturn;
}
@Override
public final int nextDoc() throws IOException {
if (lastReturn == DocIdSetIterator.NO_MORE_DOCS) return DocIdSetIterator.NO_MORE_DOCS;
DocIdSetIterator dcit = iterators[0];
int target = dcit.nextDoc();
int size = iterators.length;
int skip = 0;
int i = 1;
while (i < size) {
if (i != skip) {
dcit = iterators[i];
int docid = dcit.advance(target);
if (docid > target) {
target = docid;
if (i != 0) {
skip = i;
i = 0;
continue;
} else
skip = 0;
}
}
i++;
}
return (lastReturn = target);
}
@Override
public final int advance(int target) throws IOException {
if (lastReturn == DocIdSetIterator.NO_MORE_DOCS) return DocIdSetIterator.NO_MORE_DOCS;
DocIdSetIterator dcit = iterators[0];
target = dcit.advance(target);
int size = iterators.length;
int skip = 0;
int i = 1;
while (i < size) {
if (i != skip) {
dcit = iterators[i];
int docid = dcit.advance(target);
if (docid > target) {
target = docid;
if (i != 0) {
skip = i;
i = 0;
continue;
} else {
skip = 0;
}
}
}
i++;
}
return (lastReturn = target);
}
}
}