1 /* 2 * Copyright (C) 2018 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #ifndef NLP_SAFT_COMPONENTS_LANG_ID_MOBILE_CUSTOM_TOKENIZER_H_ 18 #define NLP_SAFT_COMPONENTS_LANG_ID_MOBILE_CUSTOM_TOKENIZER_H_ 19 20 #include <string> 21 22 #include "lang_id/common/fel/task-context.h" 23 #include "lang_id/common/lite_strings/stringpiece.h" 24 #include "lang_id/light-sentence.h" 25 26 namespace libtextclassifier3 { 27 namespace mobile { 28 namespace lang_id { 29 30 // Custom tokenizer for the LangId model. 31 class TokenizerForLangId { 32 public: 33 void Setup(TaskContext *context); 34 35 // Tokenizes |text|, placing the tokens into |sentence|. Customized for 36 // LangId. Currently (Sep 15, 2016) we tokenize on space, newline, tab, and 37 // any other 1-byte UTF8 character which is not a letter, ignore all empty 38 // tokens, and (for each of the remaining tokens) prepend "^" (special token 39 // begin marker) and append "$" (special token end marker). 40 // 41 // Tokens are stored into the "repeated Token token;" field of *sentence. 42 void Tokenize(StringPiece text, LightSentence *sentence) const; 43 44 private: 45 // If true, during tokenization, we use the lowercase version of each Unicode 46 // character from the text to tokenize. E.g., if this is true, the text "Foo 47 // bar" is tokenized as ["foo", "bar"]; otherwise, we get ["Foo", "bar"]. 48 bool lowercase_input_ = false; 49 }; 50 51 } // namespace lang_id 52 } // namespace mobile 53 } // namespace nlp_saft 54 55 #endif // NLP_SAFT_COMPONENTS_LANG_ID_MOBILE_CUSTOM_TOKENIZER_H_ 56
