Class SimpleTimeZone
- All Implemented Interfaces:
Freezable<TimeZone>
,Serializable
,Cloneable
SimpleTimeZone
is a concrete subclass of TimeZone
that represents a time zone for use with a Gregorian calendar. This
class does not handle historical changes.
Use a negative value for dayOfWeekInMonth
to indicate that
SimpleTimeZone
should count from the end of the month backwards. For
example, if Daylight Savings Time starts or ends at the last Sunday in a month, use
dayOfWeekInMonth = -1
along with dayOfWeek = Calendar.SUNDAY
to specify the rule.
- Author:
- Deborah Goldsmith, Mark Davis, Chen-Lieh Huang, Alan Liu
- See Also:
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Nested Class Summary
Nested classes/interfaces inherited from class com.ibm.icu.util.BasicTimeZone
BasicTimeZone.LocalOption
Nested classes/interfaces inherited from class com.ibm.icu.util.TimeZone
TimeZone.SystemTimeZoneType
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Field Summary
FieldsModifier and TypeFieldDescriptionstatic final int
Constant for a mode of start or end time specified as local standard time.static final int
Constant for a mode of start or end time specified as UTC.static final int
Constant for a mode of start or end time specified as local wall time.Fields inherited from class com.ibm.icu.util.BasicTimeZone
FORMER_LATTER_MASK, LOCAL_DST, LOCAL_FORMER, LOCAL_LATTER, LOCAL_STD, STD_DST_MASK
Fields inherited from class com.ibm.icu.util.TimeZone
GENERIC_LOCATION, GMT_ZONE, LONG, LONG_GENERIC, LONG_GMT, SHORT, SHORT_COMMONLY_USED, SHORT_GENERIC, SHORT_GMT, TIMEZONE_ICU, TIMEZONE_JDK, UNKNOWN_ZONE, UNKNOWN_ZONE_ID
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Constructor Summary
ConstructorsConstructorDescriptionSimpleTimeZone
(int rawOffset, String ID) Constructs a SimpleTimeZone with the given base time zone offset from GMT and time zone ID.SimpleTimeZone
(int rawOffset, String ID, int startMonth, int startDay, int startDayOfWeek, int startTime, int endMonth, int endDay, int endDayOfWeek, int endTime) Constructs a SimpleTimeZone with the given base time zone offset from GMT, time zone ID, time to start and end the daylight time.SimpleTimeZone
(int rawOffset, String ID, int startMonth, int startDay, int startDayOfWeek, int startTime, int endMonth, int endDay, int endDayOfWeek, int endTime, int dstSavings) Constructor.SimpleTimeZone
(int rawOffset, String ID, int startMonth, int startDay, int startDayOfWeek, int startTime, int startTimeMode, int endMonth, int endDay, int endDayOfWeek, int endTime, int endTimeMode, int dstSavings) Constructs a SimpleTimeZone with the given base time zone offset from GMT, time zone ID, time and its mode to start and end the daylight time. -
Method Summary
Modifier and TypeMethodDescriptionclone()
Overrides clone.Provides for the clone operation.boolean
Overrides equals.freeze()
Freezes the object.int
Returns the amount of time in ms that the clock is advanced during DST.getNextTransition
(long base, boolean inclusive) Returns the first time zone transition after the base time.int
getOffset
(int era, int year, int month, int day, int dayOfWeek, int millis) Gets the time zone offset, for current date, modified in case of daylight savings.int
getOffset
(int era, int year, int month, int day, int dayOfWeek, int millis, int monthLength) Deprecated.This API is ICU internal only.void
getOffsetFromLocal
(long date, BasicTimeZone.LocalOption nonExistingTimeOpt, BasicTimeZone.LocalOption duplicatedTimeOpt, int[] offsets) Returns time zone offsets from local wall time.getPreviousTransition
(long base, boolean inclusive) Returns the last time zone transition before the base time.int
Overrides TimeZone Gets the GMT offset for this time zone.Returns the array ofTimeZoneRule
which represents the rule of this time zone object.int
hashCode()
Overrides hashCode.boolean
hasSameRules
(TimeZone othr) Returns true if this zone has the same rules and offset as another zone.boolean
inDaylightTime
(Date date) Overrides TimeZone Queries if the give date is in Daylight Saving Time.boolean
isFrozen()
Determines whether the object has been frozen or not.boolean
Queries if this time zone is in daylight saving time or will observe daylight saving time at any future time.void
setDSTSavings
(int millisSavedDuringDST) Sets the amount of time in ms that the clock is advanced during DST.void
setEndRule
(int month, int dayOfMonth, int time) Sets the DST end rule to a fixed date within a month.void
setEndRule
(int month, int dayOfWeekInMonth, int dayOfWeek, int time) Sets the daylight savings ending rule.void
setEndRule
(int month, int dayOfMonth, int dayOfWeek, int time, boolean after) Sets the DST end rule to a weekday before or after a give date within a month, e.g., the first Monday on or after the 8th.void
Sets the time zone ID.void
setRawOffset
(int offsetMillis) Overrides TimeZone Sets the base time zone offset to GMT.void
setStartRule
(int month, int dayOfMonth, int time) Sets the DST start rule to a fixed date within a month.void
setStartRule
(int month, int dayOfWeekInMonth, int dayOfWeek, int time) Sets the daylight savings starting rule.void
setStartRule
(int month, int dayOfMonth, int dayOfWeek, int time, boolean after) Sets the DST start rule to a weekday before or after a give date within a month, e.g., the first Monday on or after the 8th.void
setStartYear
(int year) Sets the daylight savings starting year.toString()
Returns a string representation of this object.boolean
Overrides TimeZone Queries if this time zone uses Daylight Saving Time.Methods inherited from class com.ibm.icu.util.BasicTimeZone
getLocalOptionValue, getSimpleTimeZoneRulesNear, getTimeZoneRules, hasEquivalentTransitions, hasEquivalentTransitions
Methods inherited from class com.ibm.icu.util.TimeZone
countEquivalentIDs, forLocaleOrDefault, forULocaleOrDefault, getAvailableIDs, getAvailableIDs, getAvailableIDs, getAvailableIDs, getCanonicalID, getCanonicalID, getDefault, getDefaultTimeZoneType, getDisplayName, getDisplayName, getDisplayName, getDisplayName, getDisplayName, getDisplayName, getEquivalentID, getFrozenTimeZone, getID, getIDForWindowsID, getOffset, getOffset, getRegion, getTimeZone, getTimeZone, getTZDataVersion, getWindowsID, setDefault, setDefaultTimeZoneType, setICUDefault
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Field Details
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WALL_TIME
public static final int WALL_TIMEConstant for a mode of start or end time specified as local wall time.- See Also:
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STANDARD_TIME
public static final int STANDARD_TIMEConstant for a mode of start or end time specified as local standard time.- See Also:
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UTC_TIME
public static final int UTC_TIMEConstant for a mode of start or end time specified as UTC.- See Also:
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Constructor Details
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SimpleTimeZone
Constructs a SimpleTimeZone with the given base time zone offset from GMT and time zone ID. Timezone IDs can be obtained from TimeZone.getAvailableIDs. Normally you should use TimeZone.getDefault to construct a TimeZone.- Parameters:
rawOffset
- The given base time zone offset to GMT.ID
- The time zone ID which is obtained from TimeZone.getAvailableIDs.
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SimpleTimeZone
public SimpleTimeZone(int rawOffset, String ID, int startMonth, int startDay, int startDayOfWeek, int startTime, int endMonth, int endDay, int endDayOfWeek, int endTime) Constructs a SimpleTimeZone with the given base time zone offset from GMT, time zone ID, time to start and end the daylight time. Timezone IDs can be obtained from TimeZone.getAvailableIDs. Normally you should use TimeZone.getDefault to create a TimeZone. For a time zone that does not use daylight saving time, do not use this constructor; instead you should use SimpleTimeZone(rawOffset, ID). By default, this constructor specifies day-of-week-in-month rules. That is, if the startDay is 1, and the startDayOfWeek is SUNDAY, then this indicates the first Sunday in the startMonth. A startDay of -1 likewise indicates the last Sunday. However, by using negative or zero values for certain parameters, other types of rules can be specified. Day of month. To specify an exact day of the month, such as March 1, set startDayOfWeek to zero. Day of week after day of month. To specify the first day of the week occurring on or after an exact day of the month, make the day of the week negative. For example, if startDay is 5 and startDayOfWeek is -MONDAY, this indicates the first Monday on or after the 5th day of the startMonth. Day of week before day of month. To specify the last day of the week occurring on or before an exact day of the month, make the day of the week and the day of the month negative. For example, if startDay is -21 and startDayOfWeek is -WEDNESDAY, this indicates the last Wednesday on or before the 21st of the startMonth. The above examples refer to the startMonth, startDay, and startDayOfWeek; the same applies for the endMonth, endDay, and endDayOfWeek.- Parameters:
rawOffset
- The given base time zone offset to GMT.ID
- The time zone ID which is obtained from TimeZone.getAvailableIDs.startMonth
- The daylight savings starting month. Month is 0-based. eg, 0 for January.startDay
- The daylight savings starting day-of-week-in-month. Please see the member description for an example.startDayOfWeek
- The daylight savings starting day-of-week. Please see the member description for an example.startTime
- The daylight savings starting time in local wall time, which is standard time in this case. Please see the member description for an example.endMonth
- The daylight savings ending month. Month is 0-based. eg, 0 for January.endDay
- The daylight savings ending day-of-week-in-month. Please see the member description for an example.endDayOfWeek
- The daylight savings ending day-of-week. Please see the member description for an example.endTime
- The daylight savings ending time in local wall time, which is daylight time in this case. Please see the member description for an example.- Throws:
IllegalArgumentException
- the month, day, dayOfWeek, or time parameters are out of range for the start or end rule
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SimpleTimeZone
public SimpleTimeZone(int rawOffset, String ID, int startMonth, int startDay, int startDayOfWeek, int startTime, int startTimeMode, int endMonth, int endDay, int endDayOfWeek, int endTime, int endTimeMode, int dstSavings) Constructs a SimpleTimeZone with the given base time zone offset from GMT, time zone ID, time and its mode to start and end the daylight time. The mode specifies eitherWALL_TIME
orSTANDARD_TIME
orUTC_TIME
.- Parameters:
rawOffset
- The given base time zone offset to GMT.ID
- The time zone ID which is obtained from TimeZone.getAvailableIDs.startMonth
- The daylight savings starting month. Month is 0-based. eg, 0 for January.startDay
- The daylight savings starting day-of-week-in-month. Please see the member description for an example.startDayOfWeek
- The daylight savings starting day-of-week. Please see the member description for an example.startTime
- The daylight savings starting time in local wall time, which is standard time in this case. Please see the member description for an example.startTimeMode
- The mode of the start time specified by startTime.endMonth
- The daylight savings ending month. Month is 0-based. eg, 0 for January.endDay
- The daylight savings ending day-of-week-in-month. Please see the member description for an example.endDayOfWeek
- The daylight savings ending day-of-week. Please see the member description for an example.endTime
- The daylight savings ending time in local wall time, which is daylight time in this case. Please see the member description for an example.endTimeMode
- The mode of the end time specified by endTime.dstSavings
- The amount of time in ms saved during DST.- Throws:
IllegalArgumentException
- the month, day, dayOfWeek, or time parameters are out of range for the start or end rule
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SimpleTimeZone
public SimpleTimeZone(int rawOffset, String ID, int startMonth, int startDay, int startDayOfWeek, int startTime, int endMonth, int endDay, int endDayOfWeek, int endTime, int dstSavings) Constructor. This constructor is identical to the 10-argument constructor, but also takes a dstSavings parameter.- Parameters:
rawOffset
- The given base time zone offset to GMT.ID
- The time zone ID which is obtained from TimeZone.getAvailableIDs.startMonth
- The daylight savings starting month. Month is 0-based. eg, 0 for January.startDay
- The daylight savings starting day-of-week-in-month. Please see the member description for an example.startDayOfWeek
- The daylight savings starting day-of-week. Please see the member description for an example.startTime
- The daylight savings starting time in local wall time, which is standard time in this case. Please see the member description for an example.endMonth
- The daylight savings ending month. Month is 0-based. eg, 0 for January.endDay
- The daylight savings ending day-of-week-in-month. Please see the member description for an example.endDayOfWeek
- The daylight savings ending day-of-week. Please see the member description for an example.endTime
- The daylight savings ending time in local wall time, which is daylight time in this case. Please see the member description for an example.dstSavings
- The amount of time in ms saved during DST.- Throws:
IllegalArgumentException
- the month, day, dayOfWeek, or time parameters are out of range for the start or end rule
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Method Details
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setID
Sets the time zone ID. This does not change any other data in the time zone object. -
setRawOffset
public void setRawOffset(int offsetMillis) Overrides TimeZone Sets the base time zone offset to GMT. This is the offset to add "to" UTC to get local time.- Specified by:
setRawOffset
in classTimeZone
- Parameters:
offsetMillis
- the raw offset of the time zone
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getRawOffset
public int getRawOffset()Overrides TimeZone Gets the GMT offset for this time zone.- Specified by:
getRawOffset
in classTimeZone
- Returns:
- the raw offset
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setStartYear
public void setStartYear(int year) Sets the daylight savings starting year.- Parameters:
year
- The daylight savings starting year.
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setStartRule
public void setStartRule(int month, int dayOfWeekInMonth, int dayOfWeek, int time) Sets the daylight savings starting rule. For example, Daylight Savings Time starts at the second Sunday in March, at 2 AM in standard time. Therefore, you can set the start rule by calling: setStartRule(Calendar.MARCH, 2, Calendar.SUNDAY, 2*60*60*1000);- Parameters:
month
- The daylight savings starting month. Month is 0-based. eg, 0 for January.dayOfWeekInMonth
- The daylight savings starting day-of-week-in-month. Please see the member description for an example.dayOfWeek
- The daylight savings starting day-of-week. Please see the member description for an example.time
- The daylight savings starting time in local wall time, which is standard time in this case. Please see the member description for an example.- Throws:
IllegalArgumentException
- the month, dayOfWeekInMonth, dayOfWeek, or time parameters are out of range
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setStartRule
public void setStartRule(int month, int dayOfMonth, int time) Sets the DST start rule to a fixed date within a month.- Parameters:
month
- The month in which this rule occurs (0-based).dayOfMonth
- The date in that month (1-based).time
- The time of that day (number of millis after midnight) when DST takes effect in local wall time, which is standard time in this case.- Throws:
IllegalArgumentException
- the month, dayOfMonth, or time parameters are out of range
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setStartRule
public void setStartRule(int month, int dayOfMonth, int dayOfWeek, int time, boolean after) Sets the DST start rule to a weekday before or after a give date within a month, e.g., the first Monday on or after the 8th.- Parameters:
month
- The month in which this rule occurs (0-based).dayOfMonth
- A date within that month (1-based).dayOfWeek
- The day of the week on which this rule occurs.time
- The time of that day (number of millis after midnight) when DST takes effect in local wall time, which is standard time in this case.after
- If true, this rule selects the first dayOfWeek on or after dayOfMonth. If false, this rule selects the last dayOfWeek on or before dayOfMonth.- Throws:
IllegalArgumentException
- the month, dayOfMonth, dayOfWeek, or time parameters are out of range
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setEndRule
public void setEndRule(int month, int dayOfWeekInMonth, int dayOfWeek, int time) Sets the daylight savings ending rule. For example, if Daylight Savings Time ends at the last (-1) Sunday in October, at 2 AM in standard time, you can set the end rule by calling:setEndRule(Calendar.OCTOBER, -1, Calendar.SUNDAY, 2*60*60*1000);
- Parameters:
month
- The daylight savings ending month. Month is 0-based. eg, 0 for January.dayOfWeekInMonth
- The daylight savings ending day-of-week-in-month. Please see the member description for an example.dayOfWeek
- The daylight savings ending day-of-week. Please see the member description for an example.time
- The daylight savings ending time in local wall time, which is daylight time in this case. Please see the member description for an example.- Throws:
IllegalArgumentException
- the month, dayOfWeekInMonth, dayOfWeek, or time parameters are out of range
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setEndRule
public void setEndRule(int month, int dayOfMonth, int time) Sets the DST end rule to a fixed date within a month.- Parameters:
month
- The month in which this rule occurs (0-based).dayOfMonth
- The date in that month (1-based).time
- The time of that day (number of millis after midnight) when DST ends in local wall time, which is daylight time in this case.- Throws:
IllegalArgumentException
- the month, dayOfMonth, or time parameters are out of range
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setEndRule
public void setEndRule(int month, int dayOfMonth, int dayOfWeek, int time, boolean after) Sets the DST end rule to a weekday before or after a give date within a month, e.g., the first Monday on or after the 8th.- Parameters:
month
- The month in which this rule occurs (0-based).dayOfMonth
- A date within that month (1-based).dayOfWeek
- The day of the week on which this rule occurs.time
- The time of that day (number of millis after midnight) when DST ends in local wall time, which is daylight time in this case.after
- If true, this rule selects the first dayOfWeek on or after dayOfMonth. If false, this rule selects the last dayOfWeek on or before dayOfMonth.- Throws:
IllegalArgumentException
- the month, dayOfMonth, dayOfWeek, or time parameters are out of range
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setDSTSavings
public void setDSTSavings(int millisSavedDuringDST) Sets the amount of time in ms that the clock is advanced during DST.- Parameters:
millisSavedDuringDST
- the number of milliseconds the time is advanced with respect to standard time when the daylight savings rules are in effect. Typically one hour (+3600000). The amount could be negative, but not 0.
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getDSTSavings
public int getDSTSavings()Returns the amount of time in ms that the clock is advanced during DST.- Overrides:
getDSTSavings
in classTimeZone
- Returns:
- the number of milliseconds the time is advanced with respect to standard time when the daylight savings rules are in effect. Typically one hour (3600000). The amount could be negative, but not 0.
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toString
Returns a string representation of this object. -
getOffset
public int getOffset(int era, int year, int month, int day, int dayOfWeek, int millis) 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.- Specified by:
getOffset
in classTimeZone
- Parameters:
era
- the era of the given date.year
- the year in the given date.month
- the month in the given date. Month is 0-based. e.g., 0 for January.day
- the day-in-month of the given date.dayOfWeek
- the day-of-week of the given date.millis
- the millis in day in standard local time.- Returns:
- the offset to add to GMT to get local time.
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getOffset
@Deprecated public int getOffset(int era, int year, int month, int day, int dayOfWeek, int millis, int monthLength) Deprecated.This API is ICU internal only. -
getOffsetFromLocal
public void getOffsetFromLocal(long date, BasicTimeZone.LocalOption nonExistingTimeOpt, BasicTimeZone.LocalOption duplicatedTimeOpt, int[] offsets) Returns time zone offsets from local wall time.- Overrides:
getOffsetFromLocal
in classBasicTimeZone
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useDaylightTime
public boolean useDaylightTime()Overrides TimeZone Queries if this time zone uses Daylight Saving Time.- Specified by:
useDaylightTime
in classTimeZone
- Returns:
- true if this time zone uses daylight savings time,
false, otherwise.
Note:The default implementation of ICU TimeZone uses the tz database, which supports historic rule changes, for system time zones. With the implementation, there are time zones that used daylight savings time in the past, but no longer used currently. For example, Asia/Tokyo has never used daylight savings time since 1951. Most clients would expect that this method to return
false
for such case. The default implementation of this method returnstrue
when the time zone uses daylight savings time in the current (Gregorian) calendar year.
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observesDaylightTime
public boolean observesDaylightTime()Queries if this time zone is in daylight saving time or will observe daylight saving time at any future time.The default implementation in this class returns
true
ifTimeZone.useDaylightTime()
orinDaylightTime(new Date())
returnstrue
.Note: This method was added for
TimeZone
compatibility support. TheTimeZone.useDaylightTime()
method only checks the last known rule(s), therefore it may return false even the zone observes daylight saving time currently.TimeZone
addedobservesDaylightTime()
to resolve the issue. In ICU,TimeZone.useDaylightTime()
works differently. The ICU implementation checks if the zone uses daylight saving time in the current calendar year. Therefore, it will never returnfalse
if daylight saving time is currently used.ICU's TimeZone subclass implementations override this method to support the same behavior with
TimeZone.observesDaylightTime()
. UnlikeTimeZone.useDaylightTime()
, the implementation does not take past daylight saving time into account, so that this method may returnfalse
even whenTimeZone.useDaylightTime()
returnstrue
.- Overrides:
observesDaylightTime
in classTimeZone
- Returns:
true
if this time zone is in daylight saving time or will observe daylight saving time at any future time.- See Also:
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inDaylightTime
Overrides TimeZone Queries if the give date is in Daylight Saving Time.- Specified by:
inDaylightTime
in classTimeZone
- Parameters:
date
- the given Date.- Returns:
- true if the given date is in daylight savings time, false, otherwise.
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equals
Overrides equals. -
hashCode
public int hashCode()Overrides hashCode. -
clone
Overrides clone. -
hasSameRules
Returns true if this zone has the same rules and offset as another zone.- Overrides:
hasSameRules
in classTimeZone
- Parameters:
othr
- the TimeZone object to be compared with- Returns:
- true if the given zone has the same rules and offset as this one
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getNextTransition
Returns the first time zone transition after the base time.Example code:invalid input: '{@'.jcite com.ibm.icu.samples.util.timezone.BasicTimeZoneExample:---getNextTransitionExample}
- Specified by:
getNextTransition
in classBasicTimeZone
- Parameters:
base
- The base time.inclusive
- Whether the base time is inclusive or not.- Returns:
- A
Date
holding the first time zone transition time after the given base time, or null if no time zone transitions are available after the base time.
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getPreviousTransition
Returns the last time zone transition before the base time.Example code:invalid input: '{@'.jcite com.ibm.icu.samples.util.timezone.BasicTimeZoneExample:---getPreviousTransitionExample}
- Specified by:
getPreviousTransition
in classBasicTimeZone
- Parameters:
base
- The base time.inclusive
- Whether the base time is inclusive or not.- Returns:
- A
Date
holding the last time zone transition time before the given base time, or null if no time zone transitions are available before the base time.
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getTimeZoneRules
Returns the array ofTimeZoneRule
which represents the rule of this time zone object. The first element in the result array will be theInitialTimeZoneRule
instance for the initial rule. The rest will be eitherAnnualTimeZoneRule
orTimeArrayTimeZoneRule
instances representing transitions.- Specified by:
getTimeZoneRules
in classBasicTimeZone
- Returns:
- The array of
TimeZoneRule
which represents this time zone.
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isFrozen
public boolean isFrozen()Determines whether the object has been frozen or not. -
freeze
Freezes the object. -
cloneAsThawed
Provides for the clone operation. Any clone is initially unfrozen.- Specified by:
cloneAsThawed
in interfaceFreezable<TimeZone>
- Overrides:
cloneAsThawed
in classTimeZone
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