docs: @Override
  	public Map<String, String> toProperties() {
  		Map<String, String> properties = new HashMap<>();
  		properties.put(Rowtime.ROWTIME_TIMESTAMPS_TYPE, Rowtime.ROWTIME_TIMESTAMPS_TYPE_VALUE_CUSTOM);
  		properties.put(Rowtime.ROWTIME_TIMESTAMPS_CLASS, this.getClass().getName());
  		properties.put(Rowtime.ROWTIME_TIMESTAMPS_SERIALIZED, EncodingUtils.encodeObjectToString(this));
  		return properties;
  	}