/**
* Returns a copy of this date-time with the specified amount added.
* <p>
* This returns an {@code OffsetDateTime}, based on this one, with the amount
* in terms of the unit added. If it is not possible to add the amount, because the
* unit is not supported or for some other reason, an exception is thrown.
* <p>
* If the field is a {@link ChronoUnit} then the addition is implemented by
* {@link LocalDateTime#plus(long, TemporalUnit)}.
* The offset is not part of the calculation and will be unchanged in the result.
* <p>
* If the field is not a {@code ChronoUnit}, then the result of this method
* is obtained by invoking {@code TemporalUnit.addTo(Temporal, long)}
* passing {@code this} as the argument. In this case, the unit determines
* whether and how to perform the addition.
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param int $amountToAdd the amount of the unit to add to the result, may be negative
* @param TemporalUnit $unit the unit of the amount to add, not null
* @return OffsetDateTime an {@code OffsetDateTime} based on this date-time with the specified amount added, not null
* @throws DateTimeException if the addition cannot be made
* @throws UnsupportedTemporalTypeException if the unit is not supported
* @throws ArithmeticException if numeric overflow occurs
*/
public function plus($amountToAdd, TemporalUnit $unit)
{
if ($unit instanceof ChronoUnit) {
return $this->_with($this->dateTime->plus($amountToAdd, $unit), $this->offset);
}
return $unit->addTo($this, $amountToAdd);
}
/**
* Returns a copy of this date-time with the specified amount added.
* <p>
* This returns a {@code ZonedDateTime}, based on this one, with the amount
* in terms of the unit added. If it is not possible to add the amount, because the
* unit is not supported or for some other reason, an exception is thrown.
* <p>
* If the field is a {@link ChronoUnit} then the addition is implemented here.
* The zone is not part of the calculation and will be unchanged in the result.
* The calculation for date and time units differ.
* <p>
* Date units operate on the local time-line.
* The period is first added to the local date-time, then converted back
* to a zoned date-time using the zone ID.
* The conversion uses {@link #ofLocal(LocalDateTime, ZoneId, ZoneOffset)}
* with the offset before the addition.
* <p>
* Time units operate on the instant time-line.
* The period is first added to the local date-time, then converted back to
* a zoned date-time using the zone ID.
* The conversion uses {@link #ofInstant(LocalDateTime, ZoneOffset, ZoneId)}
* with the offset before the addition.
* <p>
* If the field is not a {@code ChronoUnit}, then the result of this method
* is obtained by invoking {@code TemporalUnit.addTo(Temporal, long)}
* passing {@code this} as the argument. In this case, the unit determines
* whether and how to perform the addition.
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param int $amountToAdd the amount of the unit to add to the result, may be negative
* @param TemporalUnit $unit the unit of the amount to add, not null
* @return ZonedDateTime a {@code ZonedDateTime} based on this date-time with the specified amount added, not null
* @throws DateTimeException if the addition cannot be made
* @throws UnsupportedTemporalTypeException if the unit is not supported
* @throws ArithmeticException if numeric overflow occurs
*/
public function plus($amountToAdd, TemporalUnit $unit)
{
if ($unit instanceof ChronoUnit) {
if ($unit->isDateBased()) {
return $this->resolveLocal($this->dateTime->plus($amountToAdd, $unit));
} else {
return $this->resolveInstant($this->dateTime->plus($amountToAdd, $unit));
}
}
return $unit->addTo($this, $amountToAdd);
}
