/**
* Adds a duration to this instant specifying how many times to add.
*
* <p>This will typically change the value of most fields.
*
* @param duration the duration to add, null means add zero
* @param scalar direction and amount to add, which may be negative
* @throws ArithmeticException if the result exceeds the capacity of the instant
*/
public void add(ReadableDuration duration, int scalar) {
if (duration != null) {
add(FieldUtils.safeMultiply(duration.getMillis(), scalar));
}
}
