code: public static CheckSum parse(String checksumValue) {
          if (checksumValue == null) {
              return null;
          }
          // The general layout of a checksum is:
          // <1 digit: algorithm version number>:<1..n characters alphanumeric checksum>
          // Example: 7:2cdf9876e74347162401315d34b83746
          Matcher matcher = CHECKSUM_PATTERN.matcher(checksumValue);
          if (matcher.find()) {
              return new CheckSum(matcher.group(2), Integer.parseInt(matcher.group(1)));
          } else {
              // No version information found
              return new CheckSum(checksumValue, 1);
          }
      }
docs: Parse the given storedCheckSum string value and return a new CheckSum object.