1 package org.apache.lucene.util;
4 * Licensed to the Apache Software Foundation (ASF) under one or more
5 * contributor license agreements. See the NOTICE file distributed with
6 * this work for additional information regarding copyright ownership.
7 * The ASF licenses this file to You under the Apache License, Version 2.0
8 * (the "License"); you may not use this file except in compliance with
9 * the License. You may obtain a copy of the License at
11 * http://www.apache.org/licenses/LICENSE-2.0
13 * Unless required by applicable law or agreed to in writing, software
14 * distributed under the License is distributed on an "AS IS" BASIS,
15 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16 * See the License for the specific language governing permissions and
17 * limitations under the License.
20 import java.util.BitSet;
22 import org.apache.lucene.search.DocIdSet;
23 import org.apache.lucene.search.DocIdSetIterator;
26 /** Simple DocIdSet and DocIdSetIterator backed by a BitSet */
27 public class DocIdBitSet extends DocIdSet {
28 private BitSet bitSet;
30 public DocIdBitSet(BitSet bitSet) {
35 public DocIdSetIterator iterator() {
36 return new DocIdBitSetIterator(bitSet);
39 /** This DocIdSet implementation is cacheable. */
41 public boolean isCacheable() {
46 * Returns the underlying BitSet.
48 public BitSet getBitSet() {
52 private static class DocIdBitSetIterator extends DocIdSetIterator {
54 private BitSet bitSet;
56 DocIdBitSetIterator(BitSet bitSet) {
67 public int nextDoc() {
68 // (docId + 1) on next line requires -1 initial value for docNr:
69 int d = bitSet.nextSetBit(docId + 1);
70 // -1 returned by BitSet.nextSetBit() when exhausted
71 docId = d == -1 ? NO_MORE_DOCS : d;
76 public int advance(int target) {
77 int d = bitSet.nextSetBit(target);
78 // -1 returned by BitSet.nextSetBit() when exhausted
79 docId = d == -1 ? NO_MORE_DOCS : d;