xref: /aosp_15_r20/external/icing/icing/index/iterator/doc-hit-info-iterator-and.h (revision 8b6cd535a057e39b3b86660c4aa06c99747c2136)
1 // Copyright (C) 2019 Google LLC
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 //      http://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
14 
15 #ifndef ICING_INDEX_ITERATOR_DOC_HIT_INFO_ITERATOR_AND_H_
16 #define ICING_INDEX_ITERATOR_DOC_HIT_INFO_ITERATOR_AND_H_
17 
18 #include <cstdint>
19 #include <memory>
20 #include <string>
21 #include <utility>
22 #include <vector>
23 
24 #include "icing/text_classifier/lib3/utils/base/status.h"
25 #include "icing/index/iterator/doc-hit-info-iterator.h"
26 
27 namespace icing {
28 namespace lib {
29 
30 // Given n iterators, will decide what the fastest And-iterator implementation
31 // will be.
32 std::unique_ptr<DocHitInfoIterator> CreateAndIterator(
33     std::vector<std::unique_ptr<DocHitInfoIterator>> iterators);
34 
35 // Iterate over a logical AND of two child iterators.
36 class DocHitInfoIteratorAnd : public DocHitInfoIterator {
37  public:
38   // Set the shorter iterator to short_it to get performance benefits
39   // for when an underlying iterator has a more efficient AdvanceTo.
40   explicit DocHitInfoIteratorAnd(std::unique_ptr<DocHitInfoIterator> short_it,
41                                  std::unique_ptr<DocHitInfoIterator> long_it);
42   libtextclassifier3::Status Advance() override;
43 
44   libtextclassifier3::StatusOr<TrimmedNode> TrimRightMostNode() && override;
45 
GetCallStats()46   CallStats GetCallStats() const override {
47     return short_->GetCallStats() + long_->GetCallStats();
48   }
49 
50   std::string ToString() const override;
51 
MapChildren(const ChildrenMapper & mapper)52   void MapChildren(const ChildrenMapper& mapper) override {
53     short_ = mapper(std::move(short_));
54     long_ = mapper(std::move(long_));
55   }
56 
57   void PopulateMatchedTermsStats(
58       std::vector<TermMatchInfo>* matched_terms_stats,
59       SectionIdMask filtering_section_mask = kSectionIdMaskAll) const override {
60     if (doc_hit_info_.document_id() == kInvalidDocumentId) {
61       // Current hit isn't valid, return.
62       return;
63     }
64     short_->PopulateMatchedTermsStats(matched_terms_stats,
65                                       filtering_section_mask);
66     long_->PopulateMatchedTermsStats(matched_terms_stats,
67                                      filtering_section_mask);
68   }
69 
70  private:
71   std::unique_ptr<DocHitInfoIterator> short_;
72   std::unique_ptr<DocHitInfoIterator> long_;
73 };
74 
75 // Iterate over a logical AND of multiple child iterators.
76 // NOTE: DocHitInfoIteratorAnd is a faster alternative to AND exactly 2
77 // iterators.
78 class DocHitInfoIteratorAndNary : public DocHitInfoIterator {
79  public:
80   explicit DocHitInfoIteratorAndNary(
81       std::vector<std::unique_ptr<DocHitInfoIterator>> iterators);
82 
83   libtextclassifier3::Status Advance() override;
84 
85   libtextclassifier3::StatusOr<TrimmedNode> TrimRightMostNode() && override;
86 
87   CallStats GetCallStats() const override;
88 
89   std::string ToString() const override;
90 
MapChildren(const ChildrenMapper & mapper)91   void MapChildren(const ChildrenMapper& mapper) override {
92     for (int i = 0; i < iterators_.size(); ++i) {
93       iterators_[i] = mapper(std::move(iterators_[i]));
94     }
95   }
96 
97   void PopulateMatchedTermsStats(
98       std::vector<TermMatchInfo>* matched_terms_stats,
99       SectionIdMask filtering_section_mask = kSectionIdMaskAll) const override {
100     if (doc_hit_info_.document_id() == kInvalidDocumentId) {
101       // Current hit isn't valid, return.
102       return;
103     }
104     for (size_t i = 0; i < iterators_.size(); ++i) {
105       iterators_.at(i)->PopulateMatchedTermsStats(matched_terms_stats,
106                                                   filtering_section_mask);
107     }
108   }
109 
110  private:
111   std::vector<std::unique_ptr<DocHitInfoIterator>> iterators_;
112 };
113 
114 }  // namespace lib
115 }  // namespace icing
116 
117 #endif  // ICING_INDEX_ITERATOR_DOC_HIT_INFO_ITERATOR_AND_H_
118