Home | History | Annotate | Download | only in include
      1 /*
      2  * Copyright (C) 2009 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 PINYINIME_INCLUDE_SPELLINGTABLE_H__
     18 #define PINYINIME_INCLUDE_SPELLINGTABLE_H__
     19 
     20 #include <stdlib.h>
     21 #include "./dictdef.h"
     22 
     23 namespace ime_pinyin {
     24 
     25 #ifdef ___BUILD_MODEL___
     26 
     27 const size_t kMaxSpellingSize = kMaxPinyinSize;
     28 
     29 typedef struct {
     30   char str[kMaxSpellingSize + 1];
     31   double freq;
     32 } RawSpelling, *PRawSpelling;
     33 
     34 // This class is used to store the spelling strings
     35 // The length of the input spelling string should be less or equal to the
     36 // spelling_size_ (set by init_table). If the input string is too long,
     37 // we only keep its first spelling_size_ chars.
     38 class SpellingTable {
     39  private:
     40   static const size_t kNotSupportNum = 3;
     41   static const char kNotSupportList[kNotSupportNum][kMaxSpellingSize + 1];
     42 
     43   bool need_score_;
     44 
     45   size_t spelling_max_num_;
     46 
     47   RawSpelling *raw_spellings_;
     48 
     49   // Used to store spelling strings. If the spelling table needs to calculate
     50   // score, an extra char after each spelling string is the score.
     51   // An item with a lower score has a higher probability.
     52   char *spelling_buf_;
     53   size_t spelling_size_;
     54 
     55   double total_freq_;
     56 
     57   size_t spelling_num_;
     58 
     59   double score_amplifier_;
     60 
     61   unsigned char average_score_;
     62 
     63   // If frozen is true, put_spelling() and contain() are not allowed to call.
     64   bool frozen_;
     65 
     66   size_t get_hash_pos(const char* spelling_str);
     67   size_t hash_pos_next(size_t hash_pos);
     68   void free_resource();
     69  public:
     70   SpellingTable();
     71   ~SpellingTable();
     72 
     73   // pure_spl_size is the pure maximum spelling string size. For example,
     74   // "zhuang" is the longgest item in Pinyin, so pure_spl_size should be 6.
     75   // spl_max_num is the maximum number of spelling strings to store.
     76   // need_score is used to indicate whether the caller needs to calculate a
     77   // score for each spelling.
     78   bool init_table(size_t pure_spl_size, size_t spl_max_num, bool need_score);
     79 
     80   // Put a spelling string to the table.
     81   // It always returns false if called after arrange() withtout a new
     82   // init_table() operation.
     83   // freq is the spelling's occuring count.
     84   // If the spelling has been in the table, occuring count will accumulated.
     85   bool put_spelling(const char* spelling_str, double spl_count);
     86 
     87   // Test whether a spelling string is in the table.
     88   // It always returns false, when being called after arrange() withtout a new
     89   // init_table() operation.
     90   bool contain(const char* spelling_str);
     91 
     92   // Sort the spelling strings and put them from the begin of the buffer.
     93   // Return the pointer of the sorted spelling strings.
     94   // item_size and spl_num return the item size and number of spelling.
     95   // Because each spelling uses a '\0' as terminator, the returned item_size is
     96   // at least one char longer than the spl_size parameter specified by
     97   // init_table(). If the table is initialized to calculate score, item_size
     98   // will be increased by 1, and current_spl_str[item_size - 1] stores an
     99   // unsinged char score.
    100   // An item with a lower score has a higher probability.
    101   // Do not call put_spelling() and contains() after arrange().
    102   const char* arrange(size_t *item_size, size_t *spl_num);
    103 
    104   float get_score_amplifier();
    105 
    106   unsigned char get_average_score();
    107 };
    108 #endif  // ___BUILD_MODEL___
    109 }
    110 
    111 #endif  // PINYINIME_INCLUDE_SPELLINGTABLE_H__
    112