code: public static String getFileName(String string) throws UnsupportedEncodingException {
          if (Checker.isNotEmpty(string)) {
              string = URLDecoder.decode(string, "UTF-8");
              Matcher matcher = FILE_NAME_PATTERN.matcher(string);
              if (matcher.find() && Checker.isNotEmpty(matcher.group(0))) {
                  String name = matcher.group(0).split("\\?")[0];
                  if (Checker.isNotEmpty(name)) {
                      return name;
                  }
              }
          }
          return "undefined";
      }
docs: 从文件路径中获取文件名
  
  @param string 文件路径
  
  @return {@link String}
  
  @throws UnsupportedEncodingException 异常