java.lang.Object
- org.joda.time.DateTimeZone

All Implemented Interfaces:

java.io.Serializable

Direct Known Subclasses:

CachedDateTimeZone, FixedDateTimeZone
```
public abstract class DateTimeZone
extends java.lang.Object
implements java.io.Serializable
```
DateTimeZone represents a time zone.
A time zone is a system of rules to convert time from one geographic location to another. For example, Paris, France is one hour ahead of London, England. Thus when it is 10:00 in London, it is 11:00 in Paris.
All time zone rules are expressed, for historical reasons, relative to Greenwich, London. Local time in Greenwich is referred to as Greenwich Mean Time (GMT). This is similar, but not precisely identical, to Universal Coordinated Time, or UTC. This library only uses the term UTC.
Using this system, America/Los_Angeles is expressed as UTC-08:00, or UTC-07:00 in the summer. The offset -08:00 indicates that America/Los_Angeles time is obtained from UTC by adding -08:00, that is, by subtracting 8 hours.
The offset differs in the summer because of daylight saving time, or DST. The following definitions of time are generally used:
- UTC - The reference time.
- Standard Time - The local time without a daylight saving time offset. For example, in Paris, standard time is UTC+01:00.
- Daylight Saving Time - The local time with a daylight saving time offset. This offset is typically one hour, but not always. It is typically used in most countries away from the equator. In Paris, daylight saving time is UTC+02:00.
- Wall Time - This is what a local clock on the wall reads. This will be either Standard Time or Daylight Saving Time depending on the time of year and whether the location uses Daylight Saving Time.
Unlike the Java TimeZone class, DateTimeZone is immutable. It also only supports long format time zone ids. Thus EST and ECT are not accepted. However, the factory that accepts a TimeZone will attempt to convert from the old short id to a suitable long id.
There are four approaches to loading time-zone data, which are tried in this order:
1. load the specific Provider specified by the system property org.joda.time.DateTimeZone.Provider.
2. load ZoneInfoProvider using the data in the filing system folder pointed to by system property org.joda.time.DateTimeZone.Folder.
3. load ZoneInfoProvider using the data in the classpath location org/joda/time/tz/data.
4. load UTCProvider
Unless you override the standard behaviour, the default if the third approach.
DateTimeZone is thread-safe and immutable, and all subclasses must be as well.
Since:

1.0

See Also:

Serialized Form

Field Summary

Fields
Modifier and Type Field Description

static DateTimeZone UTC
The time zone for Universal Coordinated Time

Method Summary

All Methods Static Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method	Description
`long`	`adjustOffset(long instant, boolean earlierOrLater)`	Adjusts the offset to be the earlier or later one during an overlap.
`long`	`convertLocalToUTC(long instantLocal, boolean strict)`	Converts a local instant to a standard UTC instant with the same local time.
`long`	`convertLocalToUTC(long instantLocal, boolean strict, long originalInstantUTC)`	Converts a local instant to a standard UTC instant with the same local time attempting to use the same offset as the original.
`long`	`convertUTCToLocal(long instantUTC)`	Converts a standard UTC instant to a local instant with the same local time.
`abstract boolean`	`equals(java.lang.Object object)`	Compare this datetime zone with another.
`static DateTimeZone`	`forID(java.lang.String id)`	Gets a time zone instance for the specified time zone id.
`static DateTimeZone`	`forOffsetHours(int hoursOffset)`	Gets a time zone instance for the specified offset to UTC in hours.
`static DateTimeZone`	`forOffsetHoursMinutes(int hoursOffset, int minutesOffset)`	Gets a time zone instance for the specified offset to UTC in hours and minutes.
`static DateTimeZone`	`forOffsetMillis(int millisOffset)`	Gets a time zone instance for the specified offset to UTC in milliseconds.
`static DateTimeZone`	`forTimeZone(java.util.TimeZone zone)`	Gets a time zone instance for a JDK TimeZone.
`static java.util.Set<java.lang.String>`	`getAvailableIDs()`	Gets all the available IDs supported.
`static DateTimeZone`	`getDefault()`	Gets the default time zone.
`java.lang.String`	`getID()`	Gets the ID of this datetime zone.
`long`	`getMillisKeepLocal(DateTimeZone newZone, long oldInstant)`	Gets the millisecond instant in another zone keeping the same local time.
`java.lang.String`	`getName(long instant)`	Gets the long name of this datetime zone suitable for display using the default locale.
`java.lang.String`	`getName(long instant, java.util.Locale locale)`	Gets the long name of this datetime zone suitable for display using the specified locale.
`abstract java.lang.String`	`getNameKey(long instant)`	Returns a non-localized name that is unique to this time zone.
`static NameProvider`	`getNameProvider()`	Gets the name provider factory.
`abstract int`	`getOffset(long instant)`	Gets the millisecond offset to add to UTC to get local time.
`int`	`getOffset(ReadableInstant instant)`	Gets the millisecond offset to add to UTC to get local time.
`int`	`getOffsetFromLocal(long instantLocal)`	Gets the millisecond offset to subtract from local time to get UTC time.
`static Provider`	`getProvider()`	Gets the zone provider factory.
`java.lang.String`	`getShortName(long instant)`	Gets the short name of this datetime zone suitable for display using the default locale.
`java.lang.String`	`getShortName(long instant, java.util.Locale locale)`	Gets the short name of this datetime zone suitable for display using the specified locale.
`abstract int`	`getStandardOffset(long instant)`	Gets the standard millisecond offset to add to UTC to get local time, when standard time is in effect.
`int`	`hashCode()`	Gets a hash code compatable with equals.
`abstract boolean`	`isFixed()`	Returns true if this time zone has no transitions.
`boolean`	`isLocalDateTimeGap(LocalDateTime localDateTime)`	Checks if the given `LocalDateTime` is within a gap.
`boolean`	`isStandardOffset(long instant)`	Checks whether, at a particular instant, the offset is standard or not.
`abstract long`	`nextTransition(long instant)`	Advances the given instant to where the time zone offset or name changes.
`abstract long`	`previousTransition(long instant)`	Retreats the given instant to where the time zone offset or name changes.
`static void`	`setDefault(DateTimeZone zone)`	Sets the default time zone.
`static void`	`setNameProvider(NameProvider nameProvider)`	Sets the name provider factory.
`static void`	`setProvider(Provider provider)`	Sets the zone provider factory.
`java.lang.String`	`toString()`	Gets the datetime zone as a string, which is simply its ID.
`java.util.TimeZone`	`toTimeZone()`	Get the datetime zone as a `TimeZone`.

Methods inherited from class java.lang.Object
getClass, notify, notifyAll, wait, wait, wait

- Field Detail
  - UTC
```
public static final DateTimeZone UTC
```
    The time zone for Universal Coordinated Time
- Method Detail
  - getDefault
```
public static DateTimeZone getDefault()
```
    Gets the default time zone.
    The default time zone is derived from the system property user.timezone. If that is null or is not a valid identifier, then the value of the JDK TimeZone default is converted. If that fails, UTC is used.
    NOTE: If the java.util.TimeZone default is updated after calling this method, then the change will not be picked up here.
    
    Returns:
    
    the default datetime zone object
  - setDefault
```
public static void setDefault(DateTimeZone zone)
                       throws java.lang.SecurityException
```
    Sets the default time zone.
    NOTE: Calling this method does not set the java.util.TimeZone default.
    
    Parameters:
    
    zone - the default datetime zone object, must not be null
    
    Throws:
    
    java.lang.IllegalArgumentException - if the zone is null
    
    java.lang.SecurityException - if the application has insufficient security rights
  - forID
```
public static DateTimeZone forID(java.lang.String id)
```
    Gets a time zone instance for the specified time zone id.
    The time zone id may be one of those returned by getAvailableIDs. Short ids, as accepted by TimeZone, are not accepted. All IDs must be specified in the long format. The exception is UTC, which is an acceptable id.
    Alternatively a locale independent, fixed offset, datetime zone can be specified. The form [+-]hh:mm can be used.
    
    Parameters:
    
    id - the ID of the datetime zone, null means default
    
    Returns:
    
    the DateTimeZone object for the ID
    
    Throws:
    
    java.lang.IllegalArgumentException - if the ID is not recognised
  - forOffsetHours
```
public static DateTimeZone forOffsetHours(int hoursOffset)
                                   throws java.lang.IllegalArgumentException
```
    Gets a time zone instance for the specified offset to UTC in hours. This method assumes standard length hours.
    This factory is a convenient way of constructing zones with a fixed offset.
    
    Parameters:
    
    hoursOffset - the offset in hours from UTC, from -23 to +23
    
    Returns:
    
    the DateTimeZone object for the offset
    
    Throws:
    
    java.lang.IllegalArgumentException - if the offset is too large or too small
  - forOffsetHoursMinutes
```
public static DateTimeZone forOffsetHoursMinutes(int hoursOffset,
                                                 int minutesOffset)
                                          throws java.lang.IllegalArgumentException
```
    Gets a time zone instance for the specified offset to UTC in hours and minutes. This method assumes 60 minutes in an hour, and standard length minutes.
    This factory is a convenient way of constructing zones with a fixed offset. The hours value must be in the range -23 to +23. The minutes value must be in the range -59 to +59. The following combinations of sign for the hour and minute are possible:
    Hour Minute Example Result +ve +ve (2, 15) +02:15 +ve zero (2, 0) +02:00 +ve -ve (2, -15) IllegalArgumentException zero +ve (0, 15) +00:15 zero zero (0, 0) +00:00 zero -ve (0, -15) -00:15 -ve +ve (-2, 15) -02:15 -ve zero (-2, 0) -02:00 -ve -ve (-2, -15) -02:15
    Note that in versions before 2.3, the minutes had to be zero or positive.
    Parameters:
    
    hoursOffset - the offset in hours from UTC, from -23 to +23
    
    minutesOffset - the offset in minutes from UTC, from -59 to +59
    
    Returns:
    
    the DateTimeZone object for the offset
    
    Throws:
    
    java.lang.IllegalArgumentException - if any value is out of range, the minutes are negative when the hours are positive, or the resulting offset exceeds +/- 23:59:59.000
  - forOffsetMillis
```
public static DateTimeZone forOffsetMillis(int millisOffset)
```
    Gets a time zone instance for the specified offset to UTC in milliseconds.
    
    Parameters:
    
    millisOffset - the offset in millis from UTC, from -23:59:59.999 to +23:59:59.999
    
    Returns:
    
    the DateTimeZone object for the offset
  - forTimeZone
```
public static DateTimeZone forTimeZone(java.util.TimeZone zone)
```
    Gets a time zone instance for a JDK TimeZone.
    DateTimeZone only accepts a subset of the IDs from TimeZone. The excluded IDs are the short three letter form (except UTC). This method will attempt to convert between time zones created using the short IDs and the full version.
    This method is not designed to parse time zones with rules created by applications using SimpleTimeZone directly.
    
    Parameters:
    
    zone - the zone to convert, null means default
    
    Returns:
    
    the DateTimeZone object for the zone
    
    Throws:
    
    java.lang.IllegalArgumentException - if the zone is not recognised
  - getAvailableIDs
```
public static java.util.Set<java.lang.String> getAvailableIDs()
```
    Gets all the available IDs supported.
    
    Returns:
    
    an unmodifiable Set of String IDs
  - getProvider
```
public static Provider getProvider()
```
    Gets the zone provider factory.
    The zone provider is a pluggable instance factory that supplies the actual instances of DateTimeZone.
    
    Returns:
    
    the provider
  - setProvider
```
public static void setProvider(Provider provider)
                        throws java.lang.SecurityException
```
    Sets the zone provider factory.
    The zone provider is a pluggable instance factory that supplies the actual instances of DateTimeZone.
    
    Parameters:
    
    provider - provider to use, or null for default
    
    Throws:
    
    java.lang.SecurityException - if you do not have the permission DateTimeZone.setProvider
    
    java.lang.IllegalArgumentException - if the provider is invalid
  - getNameProvider
```
public static NameProvider getNameProvider()
```
    Gets the name provider factory.
    The name provider is a pluggable instance factory that supplies the names of each DateTimeZone.
    
    Returns:
    
    the provider
  - setNameProvider
```
public static void setNameProvider(NameProvider nameProvider)
                            throws java.lang.SecurityException
```
    Sets the name provider factory.
    The name provider is a pluggable instance factory that supplies the names of each DateTimeZone.
    
    Parameters:
    
    nameProvider - provider to use, or null for default
    
    Throws:
    
    java.lang.SecurityException - if you do not have the permission DateTimeZone.setNameProvider
    
    java.lang.IllegalArgumentException - if the provider is invalid
  - getID
```
public final java.lang.String getID()
```
    Gets the ID of this datetime zone.
    
    Returns:
    
    the ID of this datetime zone
  - getNameKey
```
public abstract java.lang.String getNameKey(long instant)
```
    Returns a non-localized name that is unique to this time zone. It can be combined with id to form a unique key for fetching localized names.
    
    Parameters:
    
    instant - milliseconds from 1970-01-01T00:00:00Z to get the name for
    
    Returns:
    
    name key or null if id should be used for names
  - getShortName
```
public final java.lang.String getShortName(long instant)
```
    Gets the short name of this datetime zone suitable for display using the default locale.
    If the name is not available for the locale, then this method returns a string in the format [+-]hh:mm.
    
    Parameters:
    
    instant - milliseconds from 1970-01-01T00:00:00Z to get the name for
    
    Returns:
    
    the human-readable short name in the default locale
  - getShortName
```
public java.lang.String getShortName(long instant,
                                     java.util.Locale locale)
```
    Gets the short name of this datetime zone suitable for display using the specified locale.
    If the name is not available for the locale, then this method returns a string in the format [+-]hh:mm.
    
    Parameters:
    
    instant - milliseconds from 1970-01-01T00:00:00Z to get the name for
    
    locale - the locale to get the name for
    
    Returns:
    
    the human-readable short name in the specified locale
  - getName
```
public final java.lang.String getName(long instant)
```
    Gets the long name of this datetime zone suitable for display using the default locale.
    If the name is not available for the locale, then this method returns a string in the format [+-]hh:mm.
    
    Parameters:
    
    instant - milliseconds from 1970-01-01T00:00:00Z to get the name for
    
    Returns:
    
    the human-readable long name in the default locale
  - getName
```
public java.lang.String getName(long instant,
                                java.util.Locale locale)
```
    Gets the long name of this datetime zone suitable for display using the specified locale.
    If the name is not available for the locale, then this method returns a string in the format [+-]hh:mm.
    
    Parameters:
    
    instant - milliseconds from 1970-01-01T00:00:00Z to get the name for
    
    locale - the locale to get the name for
    
    Returns:
    
    the human-readable long name in the specified locale
  - getOffset
```
public abstract int getOffset(long instant)
```
    Gets the millisecond offset to add to UTC to get local time.
    
    Parameters:
    
    instant - milliseconds from 1970-01-01T00:00:00Z to get the offset for
    
    Returns:
    
    the millisecond offset to add to UTC to get local time
  - getOffset
```
public final int getOffset(ReadableInstant instant)
```
    Gets the millisecond offset to add to UTC to get local time.
    
    Parameters:
    
    instant - instant to get the offset for, null means now
    
    Returns:
    
    the millisecond offset to add to UTC to get local time
  - getStandardOffset
```
public abstract int getStandardOffset(long instant)
```
    Gets the standard millisecond offset to add to UTC to get local time, when standard time is in effect.
    
    Parameters:
    
    instant - milliseconds from 1970-01-01T00:00:00Z to get the offset for
    
    Returns:
    
    the millisecond offset to add to UTC to get local time
  - isStandardOffset
```
public boolean isStandardOffset(long instant)
```
    Checks whether, at a particular instant, the offset is standard or not.
    This method can be used to determine whether Summer Time (DST) applies. As a general rule, if the offset at the specified instant is standard, then either Winter time applies, or there is no Summer Time. If the instant is not standard, then Summer Time applies.
    The implementation of the method is simply whether getOffset(long) equals getStandardOffset(long) at the specified instant.
    
    Parameters:
    
    instant - milliseconds from 1970-01-01T00:00:00Z to get the offset for
    
    Returns:
    
    true if the offset at the given instant is the standard offset
    
    Since:
    
    1.5
  - getOffsetFromLocal
```
public int getOffsetFromLocal(long instantLocal)
```
    Gets the millisecond offset to subtract from local time to get UTC time. This offset can be used to undo adding the offset obtained by getOffset.
    millisLocal == millisUTC + getOffset(millisUTC) millisUTC == millisLocal - getOffsetFromLocal(millisLocal)
    NOTE: After calculating millisLocal, some error may be introduced. At offset transitions (due to DST or other historical changes), ranges of local times may map to different UTC times.
    For overlaps (where the local time is ambiguous), this method returns the offset applicable before the gap. The effect of this is that any instant calculated using the offset from an overlap will be in "summer" time.
    For gaps, this method returns the offset applicable before the gap, ie "winter" offset. However, the effect of this is that any instant calculated using the offset from a gap will be after the gap, in "summer" time.
    For example, consider a zone with a gap from 01:00 to 01:59:
    Input: 00:00 (before gap) Output: Offset applicable before gap DateTime: 00:00
    Input: 00:30 (before gap) Output: Offset applicable before gap DateTime: 00:30
    Input: 01:00 (in gap) Output: Offset applicable before gap DateTime: 02:00
    Input: 01:30 (in gap) Output: Offset applicable before gap DateTime: 02:30
    Input: 02:00 (after gap) Output: Offset applicable after gap DateTime: 02:00
    Input: 02:30 (after gap) Output: Offset applicable after gap DateTime: 02:30
    
    NOTE: Prior to v2.0, the DST overlap behaviour was not defined and varied by hemisphere. Prior to v1.5, the DST gap behaviour was also not defined. In v2.4, the documentation was clarified again.
    Parameters:
    
    instantLocal - the millisecond instant, relative to this time zone, to get the offset for
    
    Returns:
    
    the millisecond offset to subtract from local time to get UTC time
  - convertUTCToLocal
```
public long convertUTCToLocal(long instantUTC)
```
    Converts a standard UTC instant to a local instant with the same local time. This conversion is used before performing a calculation so that the calculation can be done using a simple local zone.
    
    Parameters:
    
    instantUTC - the UTC instant to convert to local
    
    Returns:
    
    the local instant with the same local time
    
    Throws:
    
    java.lang.ArithmeticException - if the result overflows a long
    
    Since:
    
    1.5
  - convertLocalToUTC
```
public long convertLocalToUTC(long instantLocal,
                              boolean strict,
                              long originalInstantUTC)
```
    Converts a local instant to a standard UTC instant with the same local time attempting to use the same offset as the original.
    This conversion is used after performing a calculation where the calculation was done using a simple local zone. Whenever possible, the same offset as the original offset will be used. This is most significant during a daylight savings overlap.
    
    Parameters:
    
    instantLocal - the local instant to convert to UTC
    
    strict - whether the conversion should reject non-existent local times
    
    originalInstantUTC - the original instant that the calculation is based on
    
    Returns:
    
    the UTC instant with the same local time,
    
    Throws:
    
    java.lang.ArithmeticException - if the result overflows a long
    
    java.lang.IllegalArgumentException - if the zone has no equivalent local time
    
    Since:
    
    2.0
  - convertLocalToUTC
```
public long convertLocalToUTC(long instantLocal,
                              boolean strict)
```
    Converts a local instant to a standard UTC instant with the same local time. This conversion is used after performing a calculation where the calculation was done using a simple local zone.
    
    Parameters:
    
    instantLocal - the local instant to convert to UTC
    
    strict - whether the conversion should reject non-existent local times
    
    Returns:
    
    the UTC instant with the same local time,
    
    Throws:
    
    java.lang.ArithmeticException - if the result overflows a long
    
    IllegalInstantException - if the zone has no equivalent local time
    
    Since:
    
    1.5
  - getMillisKeepLocal
```
public long getMillisKeepLocal(DateTimeZone newZone,
                               long oldInstant)
```
    Gets the millisecond instant in another zone keeping the same local time.
    The conversion is performed by converting the specified UTC millis to local millis in this zone, then converting back to UTC millis in the new zone.
    
    Parameters:
    
    newZone - the new zone, null means default
    
    oldInstant - the UTC millisecond instant to convert
    
    Returns:
    
    the UTC millisecond instant with the same local time in the new zone
  - isLocalDateTimeGap
```
public boolean isLocalDateTimeGap(LocalDateTime localDateTime)
```
    Checks if the given LocalDateTime is within a gap.
    When switching from standard time to Daylight Savings Time there is typically a gap where a clock hour is missing. This method identifies whether the local datetime refers to such a gap.
    
    Parameters:
    
    localDateTime - the time to check, not null
    
    Returns:
    
    true if the given datetime refers to a gap
    
    Since:
    
    1.6
  - adjustOffset
```
public long adjustOffset(long instant,
                         boolean earlierOrLater)
```
    Adjusts the offset to be the earlier or later one during an overlap.
    
    Parameters:
    
    instant - the instant to adjust
    
    earlierOrLater - false for earlier, true for later
    
    Returns:
    
    the adjusted instant millis
  - isFixed
```
public abstract boolean isFixed()
```
    Returns true if this time zone has no transitions.
    
    Returns:
    
    true if no transitions
  - nextTransition
```
public abstract long nextTransition(long instant)
```
    Advances the given instant to where the time zone offset or name changes. If the instant returned is exactly the same as passed in, then no changes occur after the given instant.
    
    Parameters:
    
    instant - milliseconds from 1970-01-01T00:00:00Z
    
    Returns:
    
    milliseconds from 1970-01-01T00:00:00Z
  - previousTransition
```
public abstract long previousTransition(long instant)
```
    Retreats the given instant to where the time zone offset or name changes. If the instant returned is exactly the same as passed in, then no changes occur before the given instant.
    
    Parameters:
    
    instant - milliseconds from 1970-01-01T00:00:00Z
    
    Returns:
    
    milliseconds from 1970-01-01T00:00:00Z
  - toTimeZone
```
public java.util.TimeZone toTimeZone()
```
    Get the datetime zone as a TimeZone.
    
    Returns:
    
    the closest matching TimeZone object
  - equals
```
public abstract boolean equals(java.lang.Object object)
```
    Compare this datetime zone with another.
    
    Overrides:
    
    equals in class java.lang.Object
    
    Parameters:
    
    object - the object to compare with
    
    Returns:
    
    true if equal, based on the ID and all internal rules
  - hashCode
```
public int hashCode()
```
    Gets a hash code compatable with equals.
    
    Overrides:
    
    hashCode in class java.lang.Object
    
    Returns:
    
    suitable hashcode
  - toString
```
public java.lang.String toString()
```
    Gets the datetime zone as a string, which is simply its ID.
    
    Overrides:
    
    toString in class java.lang.Object
    
    Returns:
    
    the id of the zone

Class DateTimeZone

Field Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

UTC

Method Detail

getDefault

setDefault

forID

forOffsetHours

forOffsetHoursMinutes

forOffsetMillis

forTimeZone

getAvailableIDs

getProvider

setProvider

getNameProvider

setNameProvider

getID

getNameKey

getShortName

getShortName

getName

getName

getOffset

getOffset

getStandardOffset

isStandardOffset

getOffsetFromLocal

convertUTCToLocal

convertLocalToUTC

convertLocalToUTC

getMillisKeepLocal

isLocalDateTimeGap

adjustOffset

isFixed

nextTransition

previousTransition

toTimeZone

equals

hashCode

toString