code: public static List<Long[]> convert(List<Term> sentence, boolean withUndefinedItem)
      {
          List<Long[]> synonymItemList = new ArrayList<Long[]>(sentence.size());
          for (Term term : sentence)
          {
              // 除掉停用词
              if (term.nature == null) continue;
              String nature = term.nature.toString();
              char firstChar = nature.charAt(0);
              switch (firstChar)
              {
                  case 'm':
                  {
                      if (!TextUtility.isAllChinese(term.word)) continue;
                  }break;
                  case 'w':
                  {
                      continue;
                  }
              }
              // 停用词
              if (CoreStopWordDictionary.contains(term.word)) continue;
              Long[] item = get(term.word);
  //            logger.trace("{} {}", wordResult.word, Arrays.toString(item));
              if (item == null)
              {
                  if (withUndefinedItem)
                  {
                      item = new Long[]{Long.MAX_VALUE / 3};
                      synonymItemList.add(item);
                  }
  
              }
              else
              {
                  synonymItemList.add(item);
              }
          }
  
          return synonymItemList;
      }
docs: 将分词结果转换为同义词列表
  @param sentence 句子
  @param withUndefinedItem 是否保留词典中没有的词语
  @return