Package org.joda.time.tz

Class CachedDateTimeZone

java.lang.Object

org.joda.time.DateTimeZone

org.joda.time.tz.CachedDateTimeZone

All Implemented Interfaces:

java.io.Serializable

public class CachedDateTimeZone
extends DateTimeZone

Improves the performance of requesting time zone offsets and name keys by caching the results. Time zones that have simple rules or are fixed should not be cached, as it is unlikely to improve performance.

CachedDateTimeZone is thread-safe and immutable.

Since:

1.0

See Also:

Serialized Form

Field Summary

Fields inherited from class org.joda.time.DateTimeZone

DEFAULT_TZ_DATA_PATH, UTC

Method Summary

Modifier and Type	Method	Description
boolean	equals(java.lang.Object obj)	Compare this datetime zone with another.
static CachedDateTimeZone	forZone(DateTimeZone zone)	Returns a new CachedDateTimeZone unless given zone is already cached.
java.lang.String	getNameKey(long instant)	Returns a non-localized name that is unique to this time zone.
int	getOffset(long instant)	Gets the millisecond offset to add to UTC to get local time.
int	getStandardOffset(long instant)	Gets the raw millisecond offset to add to UTC.
DateTimeZone	getUncachedZone()	Returns the DateTimeZone being wrapped.
int	hashCode()	Gets a hash code compatible with equals.
boolean	isFixed()	Returns true if this time zone has no transitions.
long	nextTransition(long instant)	Advances the given instant to where the time zone offset or name changes.
long	previousTransition(long instant)	Retreats the given instant to where the time zone offset or name changes.

Methods inherited from class org.joda.time.DateTimeZone

adjustOffset, convertLocalToUTC, convertLocalToUTC, convertUTCToLocal, forID, forOffsetHours, forOffsetHoursMinutes, forOffsetMillis, forTimeZone, getAvailableIDs, getDefault, getID, getMillisKeepLocal, getName, getName, getNameProvider, getOffset, getOffsetFromLocal, getProvider, getShortName, getShortName, isLocalDateTimeGap, isStandardOffset, setDefault, setNameProvider, setProvider, toString, toTimeZone

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Method Detail

forZone

public static CachedDateTimeZone forZone(DateTimeZone zone)

Returns a new CachedDateTimeZone unless given zone is already cached.

getUncachedZone

public DateTimeZone getUncachedZone()

Returns the DateTimeZone being wrapped.

getNameKey

public java.lang.String getNameKey(long instant)

Description copied from class: DateTimeZone

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.

Specified by:

getNameKey in class DateTimeZone

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

getOffset

public int getOffset(long instant)

Description copied from class: DateTimeZone

Gets the millisecond offset to add to UTC to get local time.

This returns the actual offset from UTC for the zone at the specified instant. If the method is called with a different instant, the offset returned may be different as a result of daylight saving or other government rule changes.

Specified by:

getOffset in class DateTimeZone

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

getStandardOffset

public int getStandardOffset(long instant)

Description copied from class: DateTimeZone

Gets the raw millisecond offset to add to UTC.

This should be treated as an implementation detail. End-users should use DateTimeZone.getOffset(long).

This returns the raw offset from UTC for the zone at the specified instant, effectively ignoring DST. If the method is called with a different instant, the offset returned may be different as a result of government rule changes.

This method should be named getRawOffset() but cannot be renamed for compatibility reasons.

Specified by:

getStandardOffset in class DateTimeZone

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

isFixed

public boolean isFixed()

Description copied from class: DateTimeZone

Returns true if this time zone has no transitions.

Specified by:

isFixed in class DateTimeZone

Returns:

true if no transitions

nextTransition

public long nextTransition(long instant)

Description copied from class: DateTimeZone

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.

Specified by:

nextTransition in class DateTimeZone

Parameters:

instant - milliseconds from 1970-01-01T00:00:00Z

Returns:

milliseconds from 1970-01-01T00:00:00Z

previousTransition

public long previousTransition(long instant)

Description copied from class: DateTimeZone

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.

Specified by:

previousTransition in class DateTimeZone

Parameters:

instant - milliseconds from 1970-01-01T00:00:00Z

Returns:

milliseconds from 1970-01-01T00:00:00Z

hashCode

public int hashCode()

Description copied from class: DateTimeZone

Gets a hash code compatible with equals.

Overrides:

hashCode in class DateTimeZone

Returns:

suitable hashcode

equals

public boolean equals(java.lang.Object obj)

Description copied from class: DateTimeZone

Compare this datetime zone with another.

Specified by:

equals in class DateTimeZone

Parameters:

obj - the object to compare with

Returns:

true if equal, based on the ID and all internal rules