java.util
Class TimeZone
java.lang.Object
|
+--java.util.TimeZone
- All Implemented Interfaces:
- Cloneable, Serializable
- Direct Known Subclasses:
- SimpleTimeZone
- public abstract class TimeZone
- extends Object
- implements Serializable, Cloneable
Untamed:
- See Also:
- Serialized Form
Field Summary
private String
ID
The string identifier of this
TimeZone.
static int
LONG
Enabled: A style specifier for
getDisplayName() indicating
a long name, such as "Pacific Standard Time."
static int
SHORT
Enabled: A style specifier for
getDisplayName() indicating
a short name, such as "PST."
Constructor Summary
Method Summary
Object
clone()
Suppressed: Creates a copy of this
TimeZone.
static String[]
getAvailableIDs(int rawOffset)
Enabled: Gets the available IDs according to the given time zone offset.
String
getDisplayName()
Enabled: Returns a name of this time zone suitable for presentation to the user
in the default locale.
String
getDisplayName(boolean daylight,
int style)
Enabled: Returns a name of this time zone suitable for presentation to the user
in the default locale.
String
getDisplayName(boolean daylight,
int style,
Locale locale)
Enabled: Returns a name of this time zone suitable for presentation to the user
in the specified locale.
String
getDisplayName(Locale locale)
Enabled: Returns a name of this time zone suitable for presentation to the user
in the specified locale.
int
getDSTSavings()
Enabled: Returns the amount of time to be added to local standard time
to get local wall clock time.
abstract int
getOffset(int era,
int year,
int month,
int day,
int dayOfWeek,
int milliseconds)
Enabled: Gets the time zone offset, for current date, modified in case of
daylight savings.
int
getOffset(long date)
Enabled: Returns the offset of this time zone from UTC at the specified
date.
(package private) int
getOffsets(long date,
int[] offsets)
Gets the raw GMT offset and the amount of daylight saving of this
time zone at the given time.
abstract int
getRawOffset()
Enabled: Returns the amount of time in milliseconds to add to UTC to get
standard time in this time zone.
boolean
hasSameRules(TimeZone other)
Enabled: Returns true if this zone has the same rule and offset as another zone.
abstract boolean
inDaylightTime(Date date)
Enabled: Queries if the given date is in daylight savings time in
this time zone.
static void
setDefault(TimeZone zone)
Enabled: Sets the
TimeZone that is
returned by the
getDefault method.
abstract void
setRawOffset(int offsetMillis)
Enabled: Sets the base time zone offset to GMT.
abstract boolean
useDaylightTime()
Enabled: Queries if this time zone uses daylight savings time.
Methods inherited from class java.lang.Object
Field Detail
SHORT
public static final int SHORT
- Enabled: A style specifier for
getDisplayName() indicating
a short name, such as "PST."
- Since:
- 1.2
- See Also:
LONG
LONG
public static final int LONG
- Enabled: A style specifier for
getDisplayName() indicating
a long name, such as "Pacific Standard Time."
- Since:
- 1.2
- See Also:
SHORT
ONE_MINUTE
private static final int ONE_MINUTE
ONE_HOUR
private static final int ONE_HOUR
ONE_DAY
private static final int ONE_DAY
cachedLocaleData
private static Hashtable cachedLocaleData
- Cache to hold the SimpleDateFormat objects for a Locale.
serialVersionUID
static final long serialVersionUID
ID
private String ID
- The string identifier of this
TimeZone. This is a
programmatic identifier used internally to look up TimeZone
objects from the system table and also to map them to their localized
display names. ID values are unique in the system
table but may not be for dynamically created zones.
defaultZone
private static TimeZone defaultZone
GMT_ID
static final String GMT_ID
GMT_ID_LENGTH
private static final int GMT_ID_LENGTH
Constructor Detail
TimeZone
public TimeZone()
- Enabled: Sole constructor. (For invocation by subclass constructors, typically
implicit.)
Method Detail
getOffset
public abstract int getOffset(int era,
int year,
int month,
int day,
int dayOfWeek,
int milliseconds)
- Enabled: 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:
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.milliseconds - the milliseconds in day in standard
local time.
- Returns:
- the offset in milliseconds to add to GMT to get local time.
- See Also:
Calendar.ZONE_OFFSET,
Calendar.DST_OFFSET
getOffset
public int getOffset(long date)
- Enabled: 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:
date - the date represented in milliseconds since January 1, 1970 00:00:00 GMT
- Returns:
- the amount of time in milliseconds to add to UTC to get local time.
- Since:
- 1.4
- See Also:
Calendar.ZONE_OFFSET,
Calendar.DST_OFFSET
getOffsets
int getOffsets(long date,
int[] offsets)
- Gets the raw GMT offset and the amount of daylight saving of this
time zone at the given time.
-
- Parameters:
date - the milliseconds (since January 1, 1970,
00:00:00.000 GMT) at which the time zone offset and daylight
saving amount are found
- Returns:
- the total amount of the raw GMT offset and daylight
saving at the specified date.
- See Also:
Calendar.ZONE_OFFSET,
Calendar.DST_OFFSET
setRawOffset
public abstract void setRawOffset(int offsetMillis)
- Enabled: 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:
offsetMillis - the given base time zone offset to GMT.
getRawOffset
public abstract int getRawOffset()
- Enabled: 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).
-
- Returns:
- the amount of raw offset time in milliseconds to add to UTC.
- See Also:
Calendar.ZONE_OFFSET
getID
public String getID()
- Enabled: Gets the ID of this time zone.
-
- Returns:
- the ID of this time zone.
setID
public void setID(String ID)
- Enabled: Sets the time zone ID. This does not change any other data in
the time zone object.
-
- Parameters:
ID - the new time zone ID.
getDisplayName
public final String getDisplayName()
- Enabled: Returns a name of this time zone suitable for presentation to the user
in the default locale.
This method returns the long name, not including daylight savings.
If the display name is not available for the locale,
then this method returns a string in the
normalized custom ID format.
-
- Returns:
- the human-readable name of this time zone in the default locale.
- Since:
- 1.2
getDisplayName
public final String getDisplayName(Locale locale)
- Enabled: Returns a name of this time zone suitable for presentation to the user
in the specified locale.
This method returns the long name, not including daylight savings.
If the display name is not available for the locale,
then this method returns a string in the
normalized custom ID format.
-
- Parameters:
locale - the locale in which to supply the display name.
- Returns:
- the human-readable name of this time zone in the given locale
or in the default locale if the given locale is not recognized.
- Since:
- 1.2
getDisplayName
public final String getDisplayName(boolean daylight,
int style)
- Enabled: Returns a name of this time zone suitable for presentation to the user
in the default locale.
If the display name is not available for the locale, then this
method returns a string in the
normalized custom ID format.
-
- Parameters:
daylight - if true, return the daylight savings name.style - either LONG or SHORT
- Returns:
- the human-readable name of this time zone in the default locale.
- Since:
- 1.2
getDisplayName
public String getDisplayName(boolean daylight,
int style,
Locale locale)
- Enabled: Returns a name of this time zone suitable for presentation to the user
in the specified locale.
If the display name is not available for the locale,
then this method returns a string in the
normalized custom ID format.
-
- Parameters:
daylight - if true, return the daylight savings name.style - either LONG or SHORTlocale - the locale in which to supply the display name.
- Returns:
- the human-readable name of this time zone in the given locale
or in the default locale if the given locale is not recognized.
- Since:
- 1.2
getDSTSavings
public int getDSTSavings()
- Enabled: Returns the amount of time to be added to local standard time
to get local wall clock time.
The default implementation always returns 3600000 milliseconds
(i.e., one hour) if this time zone observes Daylight Saving
Time. Otherwise, 0 (zero) is returned.
If an underlying TimeZone implementation subclass supports
historical Daylight Saving Time changes, this method returns
the known latest daylight saving value.
-
- Returns:
- the amount of saving time in milliseconds
- Since:
- 1.4
useDaylightTime
public abstract boolean useDaylightTime()
- Enabled: Queries if this time zone uses daylight savings time.
If an underlying TimeZone implementation subclass
supports historical Daylight Saving Time schedule changes, the
method refers to the latest Daylight Saving Time schedule
information.
-
- Returns:
- true if this time zone uses daylight savings time,
false, otherwise.
inDaylightTime
public abstract boolean inDaylightTime(Date date)
- Enabled: Queries if the given date is in daylight savings time in
this time zone.
-
- Parameters:
date - the given Date.
- Returns:
- true if the given date is in daylight savings time,
false, otherwise.
getTimeZone
public static TimeZone getTimeZone(String ID)
- Enabled: Gets the
TimeZone for the given ID.
-
- Parameters:
ID - 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.
- Returns:
- the specified
TimeZone, or the GMT zone if the given ID
cannot be understood.
getTimeZone
private static TimeZone getTimeZone(String ID,
boolean fallback)
-
-
getAvailableIDs
public static String[] getAvailableIDs(int rawOffset)
- Enabled: Gets the available IDs according to the given time zone offset.
-
- Parameters:
rawOffset - the given time zone GMT offset.
- Returns:
- 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 savings behavior.
getAvailableIDs
public static String[] getAvailableIDs()
- Enabled: Gets all the available IDs supported.
-
- Returns:
- an array of IDs.
getSystemTimeZoneID
private static String getSystemTimeZoneID(String javaHome,
String country)
- Gets the platform defined TimeZone ID.
-
-
getSystemGMTOffsetID
private static String getSystemGMTOffsetID()
- Gets the custom time zone ID based on the GMT offset of the
platform. (e.g., "GMT+08:00")
-
-
getDefault
public static TimeZone getDefault()
- Enabled: Gets the default
TimeZone for this host.
The source of the default TimeZone
may vary with implementation.
-
- Returns:
- a default
TimeZone. - See Also:
setDefault(java.util.TimeZone)
setDefault
public static void setDefault(TimeZone zone)
- Enabled: Sets the
TimeZone that is
returned by the getDefault method. If zone
is null, reset the default to the value it had originally when the
VM first started.
-
- Parameters:
zone - the new default time zone- See Also:
getDefault()
hasSameRules
public boolean hasSameRules(TimeZone other)
- Enabled: 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:
other - the TimeZone object to be compared with
- Returns:
- true if the other zone is not null and is the same as this one,
with the possible exception of the ID
- Since:
- 1.2
clone
public Object clone()
- Suppressed: Creates a copy of this
TimeZone.
- Overrides:
clone in class Object
- Returns:
- a clone of this
TimeZone - See Also:
java.lang.Cloneable
parseCustomTimeZone
private static final TimeZone parseCustomTimeZone(String id)
- Parses a custom time zone identifier and returns a corresponding zone.
This method doesn't support the RFC 822 time zone format. (e.g., +hhmm)
-
- Parameters:
id - a string of the custom ID form.
- Returns:
- a newly created TimeZone with the given offset and
no daylight saving time, or null if the id cannot be parsed.