/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF 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.apache.solr.search;
import java.io.IOException;
import java.util.Objects;
import org.apache.lucene.index.LeafReader;
import org.apache.lucene.index.LeafReaderContext;
import org.apache.lucene.search.DocIdSet;
import org.apache.lucene.search.DocIdSetIterator;
import org.apache.lucene.util.BitDocIdSet;
import org.apache.lucene.util.Bits;
import org.apache.lucene.util.FixedBitSet;
import org.apache.solr.common.SolrException;
/** A base class that may be useful for implementing DocSets */
abstract class DocSetBase implements DocSet {
public static FixedBitSet toBitSet(DocSet set) {
if (set instanceof DocSetBase) {
return ((DocSetBase) set).getBits();
} else {
FixedBitSet bits = new FixedBitSet(64);
for (DocIterator iter = set.iterator(); iter.hasNext();) {
int nextDoc = iter.nextDoc();
bits = FixedBitSet.ensureCapacity(bits, nextDoc);
bits.set(nextDoc);
}
return bits;
}
}
// Not implemented efficiently... for testing purposes only
@Override
public boolean equals(Object obj) {
if (!(obj instanceof DocSet)) return false;
DocSet other = (DocSet)obj;
if (this.size() != other.size()) return false;
if (this instanceof DocList && other instanceof DocList) {
// compare ordering
DocIterator i1=this.iterator();
DocIterator i2=other.iterator();
while(i1.hasNext() && i2.hasNext()) {
if (i1.nextDoc() != i2.nextDoc()) return false;
}
return true;
// don't compare matches
}
FixedBitSet bs1 = this.getBits();
FixedBitSet bs2 = toBitSet(other);
// resize both BitSets to make sure they have the same amount of zero padding
int maxNumBits = bs1.length() > bs2.length() ? bs1.length() : bs2.length();
bs1 = FixedBitSet.ensureCapacity(bs1, maxNumBits);
bs2 = FixedBitSet.ensureCapacity(bs2, maxNumBits);
// if (this.size() != other.size()) return false;
return bs1.equals(bs2);
}
public DocSet clone() {
throw new RuntimeException(new CloneNotSupportedException());
}
/**
* @throws SolrException Base implementation does not allow modifications
*/
@Override
public void add(int doc) {
throw new SolrException( SolrException.ErrorCode.SERVER_ERROR,"Unsupported Operation");
}
/**
* @throws SolrException Base implementation does not allow modifications
*/
@Override
public void addUnique(int doc) {
throw new SolrException( SolrException.ErrorCode.SERVER_ERROR,"Unsupported Operation");
}
/**
* Return a {@link FixedBitSet} with a bit set for every document in this
* {@link DocSet}. The default implementation iterates on all docs and sets
* the relevant bits. You should override if you can provide a more efficient
* implementation.
*/
protected FixedBitSet getBits() {
FixedBitSet bits = new FixedBitSet(size());
for (DocIterator iter = iterator(); iter.hasNext();) {
int nextDoc = iter.nextDoc();
bits = FixedBitSet.ensureCapacity(bits, nextDoc);
bits.set(nextDoc);
}
return bits;
}
@Override
public DocSet intersection(DocSet other) {
// intersection is overloaded in the smaller DocSets to be more
// efficient, so dispatch off of it instead.
if (!(other instanceof BitDocSet)) {
return other.intersection(this);
}
// Default... handle with bitsets.
FixedBitSet newbits = getBits().clone();
newbits.and(toBitSet(other));
return new BitDocSet(newbits);
}
@Override
public boolean intersects(DocSet other) {
// intersection is overloaded in the smaller DocSets to be more
// efficient, so dispatch off of it instead.
if (!(other instanceof BitDocSet)) {
return other.intersects(this);
}
// less efficient way: get the intersection size
return intersectionSize(other) > 0;
}
@Override
public DocSet union(DocSet other) {
FixedBitSet otherBits = toBitSet(other);
FixedBitSet newbits = FixedBitSet.ensureCapacity(getBits().clone(), otherBits.length());
newbits.or(otherBits);
return new BitDocSet(newbits);
}
@Override
public int intersectionSize(DocSet other) {
// intersection is overloaded in the smaller DocSets to be more
// efficient, so dispatch off of it instead.
if (!(other instanceof BitDocSet)) {
return other.intersectionSize(this);
}
// less efficient way: do the intersection then get its size
return intersection(other).size();
}
@Override
public int unionSize(DocSet other) {
return this.size() + other.size() - this.intersectionSize(other);
}
@Override
public DocSet andNot(DocSet other) {
FixedBitSet newbits = getBits().clone();
newbits.andNot(toBitSet(other));
return new BitDocSet(newbits);
}
@Override
public int andNotSize(DocSet other) {
return this.size() - this.intersectionSize(other);
}
@Override
public Filter getTopFilter() {
return new Filter() {
final FixedBitSet bs = getBits();
@Override
public DocIdSet getDocIdSet(final LeafReaderContext context, Bits acceptDocs) {
LeafReader reader = context.reader();
// all Solr DocSets that are used as filters only include live docs
final Bits acceptDocs2 = acceptDocs == null ? null : (reader.getLiveDocs() == acceptDocs ? null : acceptDocs);
if (context.isTopLevel) {
return BitsFilteredDocIdSet.wrap(new BitDocIdSet(bs), acceptDocs);
}
final int base = context.docBase;
final int maxDoc = reader.maxDoc();
final int max = base + maxDoc; // one past the max doc in this segment.
return BitsFilteredDocIdSet.wrap(new DocIdSet() {
@Override
public DocIdSetIterator iterator() {
return new DocIdSetIterator() {
int pos=base-1;
int adjustedDoc=-1;
@Override
public int docID() {
return adjustedDoc;
}
@Override
public int nextDoc() {
pos = bs.nextSetBit(pos+1); // TODO: this is buggy if getBits() returns a bitset that does not have a capacity of maxDoc
return adjustedDoc = pos<max ? pos-base : NO_MORE_DOCS;
}
@Override
public int advance(int target) {
if (target==NO_MORE_DOCS) return adjustedDoc=NO_MORE_DOCS;
pos = bs.nextSetBit(target+base);
return adjustedDoc = pos<max ? pos-base : NO_MORE_DOCS;
}
@Override
public long cost() {
return bs.length();
}
};
}
@Override
public long ramBytesUsed() {
return bs.ramBytesUsed();
}
@Override
public Bits bits() {
// sparse filters should not use random access
return null;
}
}, acceptDocs2);
}
@Override
public String toString(String field) {
return "DocSetTopFilter";
}
@Override
public boolean equals(Object other) {
return sameClassAs(other) &&
Objects.equals(bs, getClass().cast(other).bs);
}
@Override
public int hashCode() {
return classHash() ^ bs.hashCode();
}
};
}
@Override
public void addAllTo(DocSet target) {
DocIterator iter = iterator();
while (iter.hasNext()) {
target.add(iter.nextDoc());
}
}
/** FUTURE: for off-heap */
@Override
public void close() throws IOException {
}
}