ZoneOffsetTransition

public final class ZoneOffsetTransition extends Object
implements Comparable<ZoneOffsetTransition> Serializable

A transition between two offsets caused by a discontinuity in the local time-line.

A transition between two offsets is normally the result of a daylight savings cutover. The discontinuity is normally a gap in spring and an overlap in autumn. ZoneOffsetTransition models the transition between the two offsets.

Gaps occur where there are local date-times that simply do not exist. An example would be when the offset changes from +03:00 to +04:00. This might be described as 'the clocks will move forward one hour tonight at 1am'.

Overlaps occur where there are local date-times that exist twice. An example would be when the offset changes from +04:00 to +03:00. This might be described as 'the clocks will move back one hour tonight at 2am'.

Public Method Summary

int	compareTo(ZoneOffsetTransition transition) Compares this transition to another based on the transition instant.
boolean	equals(Object other) Checks if this object equals another.
LocalDateTime	getDateTimeAfter() Gets the local transition date-time, as would be expressed with the 'after' offset.
LocalDateTime	getDateTimeBefore() Gets the local transition date-time, as would be expressed with the 'before' offset.
Duration	getDuration() Gets the duration of the transition.
Instant	getInstant() Gets the transition instant.
ZoneOffset	getOffsetAfter() Gets the offset after the transition.
ZoneOffset	getOffsetBefore() Gets the offset before the transition.
int	hashCode() Returns a suitable hash code.
boolean	isGap() Does this transition represent a gap in the local time-line.
boolean	isOverlap() Does this transition represent an overlap in the local time-line.
boolean	isValidOffset(ZoneOffset offset) Checks if the specified offset is valid during this transition.
static ZoneOffsetTransition	of(LocalDateTime transition, ZoneOffset offsetBefore, ZoneOffset offsetAfter) Obtains an instance defining a transition between two offsets.
long	toEpochSecond() Gets the transition instant as an epoch second.
String	toString() Returns a string describing this object.

Inherited Method Summary

From class java.lang.Object

Object	clone() Creates and returns a copy of this `Object`.
boolean	equals(Object obj) Compares this instance with the specified object and indicates if they are equal.
void	finalize() Invoked when the garbage collector has detected that this instance is no longer reachable.
final Class<?>	getClass() Returns the unique instance of `Class` that represents this object's class.
int	hashCode() Returns an integer hash code for this object.
final void	notify() Causes a thread which is waiting on this object's monitor (by means of calling one of the `wait()` methods) to be woken up.
final void	notifyAll() Causes all threads which are waiting on this object's monitor (by means of calling one of the `wait()` methods) to be woken up.
String	toString() Returns a string containing a concise, human-readable description of this object.
final void	wait(long timeout, int nanos) Causes the calling thread to wait until another thread calls the `notify()` or `notifyAll()` method of this object or until the specified timeout expires.
final void	wait(long timeout) Causes the calling thread to wait until another thread calls the `notify()` or `notifyAll()` method of this object or until the specified timeout expires.
final void	wait() Causes the calling thread to wait until another thread calls the `notify()` or `notifyAll()` method of this object.

From interface java.lang.Comparable

abstract int

compareTo(ZoneOffsetTransition o)

Compares this object with the specified object for order.

Public Methods

public int compareTo (ZoneOffsetTransition transition)

Compares this transition to another based on the transition instant.

This compares the instants of each transition. The offsets are ignored, making this order inconsistent with equals.

Parameters

transition	the transition to compare to, not null

Returns

the comparator value, negative if less, positive if greater

public boolean equals (Object other)

Checks if this object equals another.

The entire state of the object is compared.

Parameters

other	the other object to compare to, null returns false

Returns

true if equal

public LocalDateTime getDateTimeAfter ()

Gets the local transition date-time, as would be expressed with the 'after' offset.

This is the first date-time after the discontinuity, when the new offset applies.

The combination of the 'before' date-time and offset represents the same instant as the 'after' date-time and offset.

Returns

the transition date-time expressed with the after offset, not null

public LocalDateTime getDateTimeBefore ()

Gets the local transition date-time, as would be expressed with the 'before' offset.

This is the date-time where the discontinuity begins expressed with the 'before' offset. At this instant, the 'after' offset is actually used, therefore the combination of this date-time and the 'before' offset will never occur.

The combination of the 'before' date-time and offset represents the same instant as the 'after' date-time and offset.

Returns

the transition date-time expressed with the before offset, not null

public Duration getDuration ()

Gets the duration of the transition.

In most cases, the transition duration is one hour, however this is not always the case. The duration will be positive for a gap and negative for an overlap. Time-zones are second-based, so the nanosecond part of the duration will be zero.

Returns

the duration of the transition, positive for gaps, negative for overlaps

public Instant getInstant ()

Gets the transition instant.

This is the instant of the discontinuity, which is defined as the first instant that the 'after' offset applies.

The methods getInstant(), getDateTimeBefore() and getDateTimeAfter() all represent the same instant.

Returns

the transition instant, not null

public ZoneOffset getOffsetAfter ()

Gets the offset after the transition.

This is the offset in use on and after the instant of the transition.

Returns

the offset after the transition, not null

public ZoneOffset getOffsetBefore ()

Gets the offset before the transition.

This is the offset in use before the instant of the transition.

Returns

the offset before the transition, not null

public int hashCode ()

Returns a suitable hash code.

Returns

the hash code

public boolean isGap ()

Does this transition represent a gap in the local time-line.

Gaps occur where there are local date-times that simply do not exist. An example would be when the offset changes from +01:00 to +02:00. This might be described as 'the clocks will move forward one hour tonight at 1am'.

Returns

true if this transition is a gap, false if it is an overlap

public boolean isOverlap ()

Does this transition represent an overlap in the local time-line.

Overlaps occur where there are local date-times that exist twice. An example would be when the offset changes from +02:00 to +01:00. This might be described as 'the clocks will move back one hour tonight at 2am'.

Returns

true if this transition is an overlap, false if it is a gap

public boolean isValidOffset (ZoneOffset offset)

Checks if the specified offset is valid during this transition.

This checks to see if the given offset will be valid at some point in the transition. A gap will always return false. An overlap will return true if the offset is either the before or after offset.

Parameters

offset	the offset to check, null returns false

Returns

true if the offset is valid during the transition

public static ZoneOffsetTransition of (LocalDateTime transition, ZoneOffset offsetBefore, ZoneOffset offsetAfter)

Obtains an instance defining a transition between two offsets.

Applications should normally obtain an instance from ZoneRules. This factory is only intended for use when creating ZoneRules.

Parameters

transition	the transition date-time at the transition, which never actually occurs, expressed local to the before offset, not null
offsetBefore	the offset before the transition, not null
offsetAfter	the offset at and after the transition, not null

Returns

the transition, not null

Throws

IllegalArgumentException	if `offsetBefore` and `offsetAfter` are equal, or `transition.getNano()` returns non-zero value

public long toEpochSecond ()

Gets the transition instant as an epoch second.

Returns

the transition epoch second

public String toString ()

Returns a string describing this object.

Returns

a string for debugging, not null