javax.time

Class ZoneOffset

java.lang.Object

javax.time.ZoneOffset

All Implemented Interfaces:

java.io.Serializable, java.lang.Comparable<ZoneOffset>, CalendricalAdjuster, CalendricalObject

public final class ZoneOffset
extends java.lang.Object
implements CalendricalObject, java.lang.Comparable<ZoneOffset>, java.io.Serializable

A time-zone offset from UTC, such as +02:00.

A time-zone offset is the period of time that a time-zone differs from UTC. This is usually a fixed number of hours and minutes.

Different parts of the world have different time-zone offsets. The rules for how offsets vary by place and time of year are captured in the ZoneId class.

For example, Paris is one hours ahead of UTC in winter and two hours ahead in summer. The ZoneId instance for Paris will reference two ZoneOffset instances - a +01:00 instance for winter, and a +02:00 instance for summer.

In 2008, time-zone offsets around the world extended from -12:00 to +14:00. To prevent any problems with that range being extended, yet still provide validation, the range of offsets is restricted to -18:00 to 18:00 inclusive.

This class is designed for use with the ISO calendar system The fields of hours, minutes and seconds make assumptions that are valid for the standard ISO definitions of those fields. This class may be used with other calendar systems providing the definition of the time fields matches those of the ISO calendar system.

Instances of ZoneOffset must be compared using equals(java.lang.Object). Implementations may choose to cache certain common offsets, however applications must not rely on such caching.

Implementation notes

This class is immutable and thread-safe.

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
static ZoneOffset	UTC The time-zone offset for UTC, with an id of 'Z'.

Method Summary

Methods

Modifier and Type	Method and Description
int	compareTo(ZoneOffset other) Compares this offset to another offset in descending order.
boolean	equals(java.lang.Object obj) Checks if this offset is equal to another offset.
<R> R	extract(java.lang.Class<R> type) Extracts date-time information in a generic way.
static ZoneOffset	from(CalendricalObject calendrical) Obtains an instance of ZoneOffset from a calendrical.
int	getHoursField() Gets the hours field of the zone offset.
java.lang.String	getID() Gets the normalized zone offset id.
int	getMinutesField() Gets the minutes field of the zone offset.
int	getSecondsField() Gets the seconds field of the zone offset.
int	getTotalSeconds() Gets the total zone offset in seconds.
int	hashCode() A hash code for this offset.
static ZoneOffset	of(java.lang.String offsetID) Obtains an instance of ZoneOffset using the id.
static ZoneOffset	ofHours(int hours) Obtains an instance of ZoneOffset using an offset in hours.
static ZoneOffset	ofHoursMinutes(int hours, int minutes) Obtains an instance of ZoneOffset using an offset in hours and minutes.
static ZoneOffset	ofHoursMinutesSeconds(int hours, int minutes, int seconds) Obtains an instance of ZoneOffset using an offset in hours, minutes and seconds.
static ZoneOffset	ofTotalSeconds(int totalSeconds) Obtains an instance of ZoneOffset specifying the total offset in seconds
java.lang.String	toString() Outputs this offset as a String, using the normalized ID.
ZoneId	toZoneId() Converts this offset to a time-zone.
ZoneOffset	with(CalendricalAdjuster adjuster) Returns a copy of this calendrical with the specified calendrical set.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

UTC

public static final ZoneOffset UTC

The time-zone offset for UTC, with an id of 'Z'.

Method Detail

of

public static ZoneOffset of(java.lang.String offsetID)

Obtains an instance of ZoneOffset using the id.

This method parses the string id of a ZoneOffset to return an instance. The parsing accepts all the formats generated by getID(), plus some additional formats:

• Z - for UTC
• +hh:mm
• -hh:mm
• +hhmm
• -hhmm
• +hh:mm:ss
• -hh:mm:ss
• +hhmmss
• -hhmmss

Note that ± means either the plus or minus symbol.

The ID of the returned offset will be normalized to one of the formats described by getID().

The maximum supported range is from +18:00 to -18:00 inclusive.

Parameters:

offsetID - the offset id, not null

Returns:

the zone-offset, not null

Throws:

java.lang.IllegalArgumentException - if the offset id is invalid

ofHours

public static ZoneOffset ofHours(int hours)

Obtains an instance of ZoneOffset using an offset in hours.

Parameters:

hours - the time-zone offset in hours, from -18 to +18

Returns:

the zone-offset, not null

Throws:

java.lang.IllegalArgumentException - if the offset is not in the required range

ofHoursMinutes

public static ZoneOffset ofHoursMinutes(int hours,
                        int minutes)

Obtains an instance of ZoneOffset using an offset in hours and minutes.

The sign of the hours and minutes components must match. Thus, if the hours is negative, the minutes must be negative or zero. If the hours is zero, the minutes may be positive, negative or zero.

Parameters:

hours - the time-zone offset in hours, from -18 to +18

minutes - the time-zone offset in minutes, from 0 to ±59, sign matches hours

Returns:

the zone-offset, not null

Throws:

java.lang.IllegalArgumentException - if the offset is not in the required range

ofHoursMinutesSeconds

public static ZoneOffset ofHoursMinutesSeconds(int hours,
                               int minutes,
                               int seconds)

Obtains an instance of ZoneOffset using an offset in hours, minutes and seconds.

The sign of the hours, minutes and seconds components must match. Thus, if the hours is negative, the minutes and seconds must be negative or zero.

Parameters:

hours - the time-zone offset in hours, from -18 to +18

minutes - the time-zone offset in minutes, from 0 to ±59, sign matches hours and seconds

seconds - the time-zone offset in seconds, from 0 to ±59, sign matches hours and minutes

Returns:

the zone-offset, not null

Throws:

java.lang.IllegalArgumentException - if the offset is not in the required range

from

public static ZoneOffset from(CalendricalObject calendrical)

Obtains an instance of ZoneOffset from a calendrical.

A calendrical represents some form of date and time information. This factory converts the arbitrary calendrical to an instance of ZoneOffset.

Parameters:

calendrical - the calendrical to convert, not null

Returns:

the zone-offset, not null

Throws:

CalendricalException - if unable to convert to an ZoneOffset

ofTotalSeconds

public static ZoneOffset ofTotalSeconds(int totalSeconds)

Obtains an instance of ZoneOffset specifying the total offset in seconds

The offset must be in the range -18:00 to +18:00, which corresponds to -64800 to +64800.

Parameters:

totalSeconds - the total time-zone offset in seconds, from -64800 to +64800

Returns:

the ZoneOffset, not null

Throws:

java.lang.IllegalArgumentException - if the offset is not in the required range

getTotalSeconds

public int getTotalSeconds()

Gets the total zone offset in seconds.

This is the primary way to access the offset amount. It returns the total of the hours, minutes and seconds fields as a single offset that can be added to a time.

Returns:

the total zone offset amount in seconds

getID

public java.lang.String getID()

Gets the normalized zone offset id.

The id is minor variation to the standard ISO-8601 formatted string for the offset. There are three formats:

• Z - for UTC (ISO-8601)
• +hh:mm or -hh:mm - if the seconds are zero (ISO-8601)
• +hh:mm:ss or -hh:mm:ss - if the seconds are non-zero (not ISO-8601)

Returns:

the zone offset ID, not null

getHoursField

public int getHoursField()

Gets the hours field of the zone offset.

The zone offset is divided into three fields - hours, minutes and seconds. This method returns the value of the hours field. The sign of the value returned by this method will match that of the minutes and seconds fields.

It is recommended to use the underlying representation of a zone offset, a count of seconds accessed using getTotalSeconds(), rather than this method.

Returns:

the hours field of the zone offset amount, from -18 to 18

getMinutesField

public int getMinutesField()

Gets the minutes field of the zone offset.

The zone offset is divided into three fields - hours, minutes and seconds. This method returns the value of the minutes field. The sign of the value returned by this method will match that of the hours and seconds fields.

It is recommended to use the underlying representation of a zone offset, a count of seconds accessed using getTotalSeconds(), rather than this method.

Returns:

the minutes field of the zone offset amount, from -59 to 59 where the sign matches the hours and seconds

getSecondsField

public int getSecondsField()

Gets the seconds field of the zone offset.

The zone offset is divided into three fields - hours, minutes and seconds. This method returns the value of the seconds field. The sign of the value returned by this method will match that of the hours and minutes fields.

It is recommended to use the underlying representation of a zone offset, a count of seconds accessed using getTotalSeconds(), rather than this method.

Returns:

the seconds field of the zone offset amount, from -59 to 59 where the sign matches the hours and minutes

extract

public <R> R extract(java.lang.Class<R> type)

Extracts date-time information in a generic way.

This method exists to fulfill the CalendricalObject interface. This implementation returns the following types:

• ZoneOffset
• DateTimeBuilder
• Class, returning ZoneOffset

Specified by:

extract in interface CalendricalObject

Type Parameters:

R - the type to extract

Parameters:

type - the type to extract, null returns null

Returns:

the extracted object, null if unable to extract

with

public ZoneOffset with(CalendricalAdjuster adjuster)

Description copied from interface: CalendricalObject

Returns a copy of this calendrical with the specified calendrical set.

This allows the manipulation of a calendrical in a general way. For example, if this calendrical is a LocalDateTime and the specified calendrical is a LocalDate, then the implementation will return a new LocalDateTime with the date changed.

An implementation must handle the following types if possible:

• DateAdjuster
• TimeAdjuster
• LocalDate
• LocalTime
• LocalDateTime
• OffsetDate
• OffsetTime
• OffsetDateTime
• ZoneOffset
• ZoneId
• Instant
• this object if the specified type is passed in

Specified by:

with in interface CalendricalObject

Parameters:

adjuster - the calendrical to set into this calendrical, null returns null

Returns:

a copy of this calendrical with the specified calendrical set, not null

toZoneId

public ZoneId toZoneId()

Converts this offset to a time-zone.

The returned time-zone will use this offset for all instants.

Returns:

the time-zone, not null

compareTo

public int compareTo(ZoneOffset other)

Compares this offset to another offset in descending order.

The offsets are compared in the order that they occur for the same time of day around the world. Thus, an offset of +10:00 comes before an offset of +09:00 and so on down to -18:00.

Specified by:

compareTo in interface java.lang.Comparable<ZoneOffset>

Parameters:

other - the other date to compare to, not null

Returns:

the comparator value, negative if less, postive if greater

Throws:

java.lang.NullPointerException - if other is null

equals

public boolean equals(java.lang.Object obj)

Checks if this offset is equal to another offset.

The comparison is based on the amount of the offset in seconds.

Overrides:

equals in class java.lang.Object

Parameters:

obj - the object to check, null returns false

Returns:

true if this is equal to the other offset

hashCode

public int hashCode()

A hash code for this offset.

Overrides:

hashCode in class java.lang.Object

Returns:

a suitable hash code

toString

public java.lang.String toString()

Outputs this offset as a String, using the normalized ID.

Overrides:

toString in class java.lang.Object

Returns:

a string representation of this offset, not null