Converts this {@code OffsetTime} to the number of seconds since the epoch
of 1970-01-01T00:00:00Z.
!(p)
This combines this offset time with the specified date to calculate the
epoch-second value, which is the number of elapsed seconds from
1970-01-01T00:00:00Z.
Instants on the time-line after the epoch are positive, earlier
are negative.
@param date the localdate, not null
@return the number of seconds since the epoch of 1970-01-01T00:00:00Z, may be negative
@since 9
Converts this {@code OffsetTime} to the number of seconds since the epoch of 1970-01-01T00:00:00Z. !(p) This combines this offset time with the specified date to calculate the epoch-second value, which is the number of elapsed seconds from 1970-01-01T00:00:00Z. Instants on the time-line after the epoch are positive, earlier are negative.
@param date the localdate, not null @return the number of seconds since the epoch of 1970-01-01T00:00:00Z, may be negative @since 9