code: private String gotExtractedValue(String string) {
          if (!isEmpty(value_extract_regex)) {
              Pattern pattern = Pattern.compile(value_extract_regex);
              Matcher ma = pattern.matcher(string);
              String result = "";
              while (ma.find()) {
                  result += ma.group(0);
              }
              return result;
          }
          return string;
      }
docs: 从输入中提取数据