docs: public final String updateFilenameHashCode(String fileName)
      {
          String nextName = null;
          int len = fileName.length();
          int last_ = (len > 9 && (fileName.charAt(len - 9) == '_')) ? len - 9 : -1;
          // input file name must have a trailing "_" follows by 8 hex digits
          // and check to make sure the last 8 characters are all hex digits
          if (last_ != -1 && allHexDigits(fileName, ++last_, len))
          {
              // If version 1 hash suffix, then update to version 2 has suffix
              if (ivHashVersion == 1) // d369262.3
              {
                  ivHashSuffix = getHashSuffix(true);
                  nextName = fileName.substring(0, last_) + ivHashSuffix;
              }
              // if version 2 hash suffix, and EJB 1.1, then remove hash suffix
              else if (ivHashVersion == 2 && ivVersion == EJB_1X) // d369262.3
              {
                  ivHashVersion = 0;
                  nextName = fileName.substring(0, (last_ - 1));
              }
              // All other scenarios.... just fall out and return null
          }
          return nextName;
      }