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_NOT_H_ 16 #define ICING_INDEX_ITERATOR_DOC_HIT_INFO_ITERATOR_NOT_H_ 17 18 #include <cstdint> 19 #include <memory> 20 #include <string> 21 22 #include "icing/text_classifier/lib3/utils/base/status.h" 23 #include "icing/index/iterator/doc-hit-info-iterator-all-document-id.h" 24 #include "icing/index/iterator/doc-hit-info-iterator.h" 25 #include "icing/store/document-id.h" 26 27 namespace icing { 28 namespace lib { 29 30 // Iterator that will return all documents that are *not* specified by the 31 // to_be_excluded_iterator. 32 // 33 // NOTE: The hit_intersect_section_ids_mask is meaningless for this iterator. 34 // When this iterator produces a result, it's because the Document was not 35 // present in the to_be_excluded_iterator. There is no concept of the Document 36 // having been chosen because it's term was in a specific section. Since we 37 // don't know anything about the sections for the Document, the 38 // hit_intersect_section_ids_mask is always kSectionIdMaskNone. Correspondingly, 39 // this means that the doc_hit_info.hit_section_ids_mask will also always be 40 // kSectionIdMaskNone. 41 class DocHitInfoIteratorNot : public DocHitInfoIterator { 42 public: 43 // to_be_excluded_iterator: The results of this iterator will be excluded 44 // from this iterator's results. 45 // document_id_limit: The DocumentId that represents the most recently added 46 // Document to the DocumentStore 47 explicit DocHitInfoIteratorNot( 48 std::unique_ptr<DocHitInfoIterator> to_be_excluded_iterator, 49 const DocumentId document_id_limit); 50 51 libtextclassifier3::Status Advance() override; 52 53 // The NOT operator is not suppose to be trimmed. 54 // We shouldn't generate suggestion for the last term if the last term belongs 55 // to NOT operator. 56 libtextclassifier3::StatusOr<TrimmedNode> TrimRightMostNode() && override; 57 58 int32_t GetNumBlocksInspected() const override; 59 60 int32_t GetNumLeafAdvanceCalls() const override; 61 62 std::string ToString() const override; 63 64 private: 65 std::unique_ptr<DocHitInfoIterator> to_be_excluded_; 66 DocHitInfoIteratorAllDocumentId all_document_id_iterator_; 67 }; 68 69 } // namespace lib 70 } // namespace icing 71 72 #endif // ICING_INDEX_ITERATOR_DOC_HIT_INFO_ITERATOR_NOT_H_ 73