code: public static long decodeRealNumberRangeLong(String value, long offsetValue) {
          long offsetNumber = Long.parseLong(value, 10);
          return (long) (offsetNumber - offsetValue);
      }
docs: Decodes a long value from the string representation that was created by using
  encodeRealNumberRange(..) function.
  
  @param value
  string representation of the long value
  @param offsetValue
  offset value that was used in the original encoding
  @return original long value