code: public final Timestamp addSecond(int amount)
      {
          long delta = (long) amount * 1000;
          return addMillisForPrecision(delta, Precision.SECOND, false);
      }
docs: Returns a timestamp relative to this one by the given number of seconds.
  <p>
  This method always returns a Timestamp with SECOND precision.
  For example, adding one second to {@code 2011T} results in
  {@code 2011-01-01T00:00:01-00:00}. To receive a Timestamp that always
  maintains the same precision as the original, use {@link #adjustSecond(int)}.
  
  @param amount a number of seconds.