1 package org.apache.lucene.search;
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.io.IOException;
23 * Abstract decorator class of a DocIdSetIterator
24 * implementation that provides on-demand filter/validation
25 * mechanism on an underlying DocIdSetIterator. See {@link
28 public abstract class FilteredDocIdSetIterator extends DocIdSetIterator {
29 protected DocIdSetIterator _innerIter;
34 * @param innerIter Underlying DocIdSetIterator.
36 public FilteredDocIdSetIterator(DocIdSetIterator innerIter) {
37 if (innerIter == null) {
38 throw new IllegalArgumentException("null iterator");
40 _innerIter = innerIter;
45 * Validation method to determine whether a docid should be in the result set.
46 * @param doc docid to be tested
47 * @return true if input docid should be in the result set, false otherwise.
48 * @see #FilteredDocIdSetIterator(DocIdSetIterator)
50 abstract protected boolean match(int doc) throws IOException;
58 public int nextDoc() throws IOException {
59 while ((doc = _innerIter.nextDoc()) != NO_MORE_DOCS) {
68 public int advance(int target) throws IOException {
69 doc = _innerIter.advance(target);
70 if (doc != NO_MORE_DOCS) {
74 while ((doc = _innerIter.nextDoc()) != NO_MORE_DOCS) {