TimeZone
abstract class TimeZone : Cloneable, Serializable
kotlin.Any | |
↳ | java.util.TimeZone |
represents a time zone offset, and also figures out daylight savings.
Typically, you get a TimeZone
using getDefault
which creates a TimeZone
based on the time zone where the program is running. For example, for a program running in Japan, getDefault
creates a TimeZone
object based on Japanese Standard Time.
You can also get a TimeZone
using getTimeZone
along with a time zone ID. For instance, the time zone ID for the U.S. Pacific Time zone is "America/Los_Angeles". So, you can get a U.S. Pacific Time TimeZone
object with:
getAvailableIDs
method to iterate through all the supported time zone IDs. You can then choose a supported ID to get a TimeZone
. If the time zone you want is not represented by one of the supported IDs, then a custom time zone ID can be specified to produce a TimeZone. The syntax of a custom time zone ID is:
<a id="CustomID"><i>CustomID:</i></a><code>GMT</code><i>Sign</i><i>Hours</i><code>:</code><i>Minutes</i><code>:</code><i>Seconds</i><code>GMT</code><i>Sign</i><i>Hours</i><code>:</code><i>Minutes</i><code>GMT</code><i>Sign</i><i>Hours</i><i>Minutes</i><code>GMT</code><i>Sign</i><i>Hours</i><i>Sign:</i>one of <code>+ -</code><i>Hours:</i><i>Digit</i><i>Digit</i><i>Digit</i><i>Minutes:</i><i>Digit</i><i>Digit</i><i>Seconds:</i><i>Digit</i><i>Digit</i><i>Digit:</i>one of <code>0 1 2 3 4 5 6 7 8 9</code>
The format is locale independent and digits must be taken from the Basic Latin block of the Unicode standard. No daylight saving time transition schedule can be specified with a custom time zone ID. If the specified string doesn't match the syntax, "GMT"
is used.
When creating a TimeZone
, the specified custom time zone ID is normalized in the following syntax:
<a id="NormalizedCustomID"><i>NormalizedCustomID:</i></a><code>GMT</code><i>Sign</i><i>TwoDigitHours</i><code>:</code><i>Minutes</i>[<i>ColonSeconds</i>] <i>Sign:</i>one of <code>+ -</code><i>TwoDigitHours:</i><i>Digit</i><i>Digit</i><i>Minutes:</i><i>Digit</i><i>Digit</i><i>ColonSeconds:</i><code>:</code><i>Digit</i><i>Digit</i><i>Digit:</i>one of <code>0 1 2 3 4 5 6 7 8 9</code>
Three-letter time zone IDs
For compatibility with JDK 1.1.x, some other three-letter time zone IDs (such as "PST", "CTT", "AST") are also supported. However, their use is deprecated because the same abbreviation is often used for multiple time zones (for example, "CST" could be U.S. "Central Standard Time" and "China Standard Time"), and the Java platform can then only recognize one of them.Summary
Constants | |
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static Int |
A style specifier for |
static Int |
A style specifier for |
Public constructors | |
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TimeZone() Sole constructor. |
Public methods | |
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open Any |
clone() Creates a copy of this |
open static Array<String!>! |
Gets all the available IDs supported. |
open static Array<String!>! |
getAvailableIDs(rawOffset: Int) Gets the available IDs according to the given time zone offset in milliseconds. |
open Int |
Returns the amount of time to be added to local standard time to get local wall clock time. |
open static TimeZone! |
Gets the default |
String! |
Returns a long standard time name of this |
String! |
getDisplayName(daylight: Boolean, style: Int) Returns a name in the specified |
open String! |
getDisplayName(daylightTime: Boolean, style: Int, locale: Locale!) Returns the |
String! |
getDisplayName(locale: Locale!) Returns a long standard time name of this |
open String! |
getID() Gets the ID of this time zone. |
abstract Int |
Gets the time zone offset, for current date, modified in case of daylight savings. |
open Int |
Returns the offset of this time zone from UTC at the specified date. |
abstract Int |
Returns the amount of time in milliseconds to add to UTC to get standard time in this time zone. |
open static TimeZone! |
getTimeZone(id: String!) Gets the |
open static TimeZone! |
getTimeZone(zoneId: ZoneId!) Gets the |
open Boolean |
hasSameRules(other: TimeZone!) Returns true if this zone has the same rule and offset as another zone. |
abstract Boolean |
inDaylightTime(date: Date!) Queries if the given |
open Boolean |
Returns |
open static Unit |
setDefault(timeZone: TimeZone!) Sets the |
open Unit |
Sets the time zone ID. |
abstract Unit |
setRawOffset(offsetMillis: Int) Sets the base time zone offset to GMT. |
open ZoneId! |
toZoneId() Converts this |
abstract Boolean |
Queries if this |
Constants
LONG
static val LONG: Int
A style specifier for getDisplayName()
indicating a long name, such as "Pacific Standard Time."
Value: 1
See Also
SHORT
static val SHORT: Int
A style specifier for getDisplayName()
indicating a short name, such as "PST."
Value: 0
See Also
Public constructors
TimeZone
TimeZone()
Sole constructor. (For invocation by subclass constructors, typically implicit.)
Public methods
clone
open fun clone(): Any
Creates a copy of this TimeZone
.
Return | |
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Any |
a clone of this TimeZone |
Exceptions | |
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java.lang.CloneNotSupportedException |
if the object's class does not support the Cloneable interface. Subclasses that override the clone method can also throw this exception to indicate that an instance cannot be cloned. |
getAvailableIDs
open static fun getAvailableIDs(): Array<String!>!
Gets all the available IDs supported.
Return | |
---|---|
Array<String!>! |
an array of IDs. |
getAvailableIDs
open static fun getAvailableIDs(rawOffset: Int): Array<String!>!
Gets the available IDs according to the given time zone offset in milliseconds.
Parameters | |
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rawOffset |
Int: the given time zone GMT offset in milliseconds. |
Return | |
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Array<String!>! |
an array of IDs, where the time zone for that ID has the specified GMT offset. For example, "America/Phoenix" and "America/Denver" both have GMT-07:00, but differ in daylight saving behavior. |
See Also
getDSTSavings
open fun getDSTSavings(): Int
Returns the amount of time to be added to local standard time to get local wall clock time.
The default implementation returns 3600000 milliseconds (i.e., one hour) if a call to useDaylightTime()
returns true
. Otherwise, 0 (zero) is returned.
If an underlying TimeZone
implementation subclass supports historical and future Daylight Saving Time schedule changes, this method returns the amount of saving time of the last known Daylight Saving Time rule that can be a future prediction.
If the amount of saving time at any given time stamp is required, construct a Calendar
with this TimeZone
and the time stamp, and call Calendar.get
(
Calendar.DST_OFFSET
)
.
Return | |
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Int |
the amount of saving time in milliseconds |
getDefault
open static fun getDefault(): TimeZone!
Gets the default TimeZone
for this host. The source of the default TimeZone
may vary with implementation.
Return | |
---|---|
TimeZone! |
a default TimeZone . |
See Also
getDisplayName
fun getDisplayName(): String!
Returns a long standard time name of this TimeZone
suitable for presentation to the user in the default locale.
This method is equivalent to:
{@snippet lang=java : * // @link substring="LONG" target="#LONG" : * getDisplayName(false, LONG, * // @link substring="Locale.Category.DISPLAY" target="Locale.Category#DISPLAY" : * Locale.getDefault(Locale.Category.DISPLAY)); * }Return | |
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String! |
the human-readable name of this time zone in the default locale. |
getDisplayName
fun getDisplayName(
daylight: Boolean,
style: Int
): String!
Returns a name in the specified style
of this TimeZone
suitable for presentation to the user in the default locale. If the specified daylight
is true
, a Daylight Saving Time name is returned (even if this TimeZone
doesn't observe Daylight Saving Time). Otherwise, a Standard Time name is returned.
This method is equivalent to:
{@snippet lang=java : * getDisplayName(daylight, style, * // @link substring="Locale.Category.DISPLAY" target="Locale.Category#DISPLAY" : * Locale.getDefault(Locale.Category.DISPLAY)); * }Parameters | |
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daylight |
Boolean: true specifying a Daylight Saving Time name, or false specifying a Standard Time name |
style |
Int: either LONG or SHORT |
Return | |
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String! |
the human-readable name of this time zone in the default locale. |
Exceptions | |
---|---|
java.lang.IllegalArgumentException |
if style is invalid. |
getDisplayName
open fun getDisplayName(
daylightTime: Boolean,
style: Int,
locale: Locale!
): String!
Returns the short
or long
name of this time zone with either standard or daylight time, as written in locale
. If the name is not available, the result is in the format GMT[+-]hh:mm
.
Parameters | |
---|---|
daylightTime |
Boolean: true specifying a Daylight Saving Time name, or false specifying a Standard Time name |
style |
Int: either LONG or SHORT |
locale |
Locale!: the locale in which to supply the display name. |
Return | |
---|---|
String! |
the human-readable name of this time zone in the given locale. |
Exceptions | |
---|---|
java.lang.IllegalArgumentException |
This method may throw an IllegalArgumentException if style is invalid. |
java.lang.NullPointerException |
This method may throw a NullPointerException if ID is null |
getDisplayName
fun getDisplayName(locale: Locale!): String!
Returns a long standard time name of this TimeZone
suitable for presentation to the user in the specified locale
.
This method is equivalent to:
{@snippet lang=java : * // @link substring="LONG" target="#LONG" : * getDisplayName(false, LONG, locale); * }Parameters | |
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locale |
Locale!: the locale in which to supply the display name. |
Return | |
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String! |
the human-readable name of this time zone in the given locale. |
Exceptions | |
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java.lang.NullPointerException |
if locale is null . |
getID
open fun getID(): String!
Gets the ID of this time zone.
Return | |
---|---|
String! |
the ID of this time zone. |
getOffset
abstract fun getOffset(
era: Int,
year: Int,
month: Int,
day: Int,
dayOfWeek: Int,
milliseconds: Int
): Int
Gets the time zone offset, for current date, modified in case of daylight savings. This is the offset to add to UTC to get local time.
This method returns a historically correct offset if an underlying TimeZone
implementation subclass supports historical Daylight Saving Time schedule and GMT offset changes.
Parameters | |
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era |
Int: the era of the given date. |
year |
Int: the year in the given date. |
month |
Int: the month in the given date. Month is 0-based. e.g., 0 for January. |
day |
Int: the day-in-month of the given date. |
dayOfWeek |
Int: the day-of-week of the given date. |
milliseconds |
Int: the milliseconds in day in standard local time. |
Return | |
---|---|
Int |
the offset in milliseconds to add to GMT to get local time. |
getOffset
open fun getOffset(date: Long): Int
Returns the offset of this time zone from UTC at the specified date. If Daylight Saving Time is in effect at the specified date, the offset value is adjusted with the amount of daylight saving.
This method returns a historically correct offset value if an underlying TimeZone implementation subclass supports historical Daylight Saving Time schedule and GMT offset changes.
Parameters | |
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date |
Long: the date represented in milliseconds since January 1, 1970 00:00:00 GMT |
Return | |
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Int |
the amount of time in milliseconds to add to UTC to get local time. |
getRawOffset
abstract fun getRawOffset(): Int
Returns the amount of time in milliseconds to add to UTC to get standard time in this time zone. Because this value is not affected by daylight saving time, it is called raw offset.
If an underlying TimeZone
implementation subclass supports historical GMT offset changes, the method returns the raw offset value of the current date. In Honolulu, for example, its raw offset changed from GMT-10:30 to GMT-10:00 in 1947, and this method always returns -36000000 milliseconds (i.e., -10 hours).
Return | |
---|---|
Int |
the amount of raw offset time in milliseconds to add to UTC. |
See Also
getTimeZone
open static fun getTimeZone(id: String!): TimeZone!
Gets the TimeZone
for the given ID.
Parameters | |
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id |
String!: the ID for a TimeZone , either an abbreviation such as "PST", a full name such as "America/Los_Angeles", or a custom ID such as "GMT-8:00". Note that the support of abbreviations is for JDK 1.1.x compatibility only and full names should be used. |
Return | |
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TimeZone! |
the specified TimeZone , or the GMT zone if the given ID cannot be understood. |
Exceptions | |
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java.lang.NullPointerException |
if ID is null |
getTimeZone
open static fun getTimeZone(zoneId: ZoneId!): TimeZone!
Gets the TimeZone
for the given zoneId
.
Parameters | |
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zoneId |
ZoneId!: a ZoneId from which the time zone ID is obtained |
Return | |
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TimeZone! |
the specified TimeZone , or the GMT zone if the given ID cannot be understood. |
Exceptions | |
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java.lang.NullPointerException |
if zoneId is null |
hasSameRules
open fun hasSameRules(other: TimeZone!): Boolean
Returns true if this zone has the same rule and offset as another zone. That is, if this zone differs only in ID, if at all. Returns false if the other zone is null.
Parameters | |
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other |
TimeZone!: the TimeZone object to be compared with |
Return | |
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Boolean |
true if the other zone is not null and is the same as this one, with the possible exception of the ID |
inDaylightTime
abstract fun inDaylightTime(date: Date!): Boolean
Queries if the given date
is in Daylight Saving Time in this time zone.
Parameters | |
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date |
Date!: the given Date. |
Return | |
---|---|
Boolean |
true if the given date is in Daylight Saving Time, false , otherwise. |
Exceptions | |
---|---|
java.lang.NullPointerException |
This method may throw a NullPointerException if date is null |
observesDaylightTime
open fun observesDaylightTime(): Boolean
Returns true
if this TimeZone
is currently in Daylight Saving Time, or if a transition from Standard Time to Daylight Saving Time occurs at any future time.
The default implementation returns true
if useDaylightTime()
or inDaylightTime(new Date())
returns true
.
Return | |
---|---|
Boolean |
true if this TimeZone is currently in Daylight Saving Time, or if a transition from Standard Time to Daylight Saving Time occurs at any future time; false otherwise. |
setDefault
open static fun setDefault(timeZone: TimeZone!): Unit
Sets the TimeZone
that is returned by the getDefault
method. zone
is cached. If zone
is null, the cached default TimeZone
is cleared. This method doesn't change the value of the user.timezone
property.
Parameters | |
---|---|
timeZone |
TimeZone!: the new default TimeZone , or null |
See Also
setID
open fun setID(ID: String!): Unit
Sets the time zone ID. This does not change any other data in the time zone object.
Parameters | |
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ID |
String!: the new time zone ID. |
Exceptions | |
---|---|
java.lang.NullPointerException |
This method may throw a NullPointerException if ID is null |
setRawOffset
abstract fun setRawOffset(offsetMillis: Int): Unit
Sets the base time zone offset to GMT. This is the offset to add to UTC to get local time.
If an underlying TimeZone
implementation subclass supports historical GMT offset changes, the specified GMT offset is set as the latest GMT offset and the difference from the known latest GMT offset value is used to adjust all historical GMT offset values.
Parameters | |
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offsetMillis |
Int: the given base time zone offset to GMT. |
toZoneId
open fun toZoneId(): ZoneId!
Converts this TimeZone
object to a ZoneId
.
Return | |
---|---|
ZoneId! |
a ZoneId representing the same time zone as this TimeZone |
useDaylightTime
abstract fun useDaylightTime(): Boolean
Queries if this TimeZone
uses Daylight Saving Time.
If an underlying TimeZone
implementation subclass supports historical and future Daylight Saving Time schedule changes, this method refers to the last known Daylight Saving Time rule that can be a future prediction and may not be the same as the current rule. Consider calling observesDaylightTime()
if the current rule should also be taken into account.
Return | |
---|---|
Boolean |
true if this TimeZone uses Daylight Saving Time, false , otherwise. |