code: private long getSnapshotHighWatermark(WatermarkType watermarkType) {
      LOG.debug("Getting snapshot high water mark");
      if (isSimpleWatermark(watermarkType)) {
        return ConfigurationKeys.DEFAULT_WATERMARK_VALUE;
      }
      String timeZone = this.state.getProp(ConfigurationKeys.SOURCE_TIMEZONE);
      return Long.parseLong(Utils.dateTimeToString(getCurrentTime(timeZone), WATERMARKTIMEFORMAT, timeZone));
    }
docs: Get snapshot high water mark
  
  @param watermarkType Watermark type
  @return snapshot high water mark