code: public static String getSummary(String document, int max_length, String sentence_separator)
      {
          // Parameter size in this method refers to the string length of the summary required;
          // The actual length of the summary generated may be short than the required length, but never longer;
          return TextRankSentence.getSummary(document, max_length, sentence_separator);
      }
docs: 自动摘要
  
  @param document           目标文档
  @param max_length         需要摘要的长度
  @param sentence_separator 分割目标文档时的句子分割符，正则格式， 如：[。？?！!；;]
  @return 摘要文本