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/*
* @(#)TimeZone.java 1.51 00/01/19
*
* Copyright (C) 1996-2012, International Business Machines
* Corporation and others. All Rights Reserved.
*/
package com.ibm.icu.util;
import java.io.Serializable;
import java.util.Date;
import java.util.Locale;
import java.util.MissingResourceException;
import java.util.Set;
import java.util.logging.Logger;
import com.ibm.icu.impl.Grego;
import com.ibm.icu.impl.ICUConfig;
import com.ibm.icu.impl.JavaTimeZone;
import com.ibm.icu.impl.TimeZoneAdapter;
import com.ibm.icu.impl.ZoneMeta;
import com.ibm.icu.text.TimeZoneFormat;
import com.ibm.icu.text.TimeZoneFormat.Style;
import com.ibm.icu.text.TimeZoneFormat.TimeType;
import com.ibm.icu.text.TimeZoneNames;
import com.ibm.icu.text.TimeZoneNames.NameType;
import com.ibm.icu.util.ULocale.Category;
/**
* {@icuenhanced java.util.TimeZone}.{@icu _usage_}
*
* TimeZone represents a time zone offset, and also computes daylight
* savings.
*
*
Typically, you get a TimeZone using {@link #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 {@link #getTimeZone(String)}
* 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:
*
*
*
* TimeZone tz = TimeZone.getTimeZone("America/Los_Angeles");
*
*
* You can use the {@link #getAvailableIDs()} method to iterate through
* all the supported time zone IDs, or getCanonicalID method to check
* if a time zone ID is supported or not. 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 you can create a custom time zone ID with
* the following syntax:
*
*
*
* GMT[+|-]hh[[:]mm]
*
*
*
* For example, you might specify GMT+14:00 as a custom
* time zone ID. The TimeZone that is returned
* when you specify a custom time zone ID uses the specified
* offset from GMT(=UTC) and does not observe daylight saving
* time. For example, you might specify GMT+14:00 as a custom
* time zone ID to create a TimeZone representing 14 hours ahead
* of GMT (with no daylight saving time). In addition,
* getCanonicalID can also be used to
* normalize a custom time zone ID.
*
* 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.
*
*
Note: Starting from ICU4J 4.0, you can optionally choose
* JDK TimeZone as the time zone implementation. The TimeZone factory
* method getTimeZone creates an instance of ICU's own TimeZone
* subclass by default. If you want to use the JDK implementation always, you can
* set the default time zone implementation type by the new method
* setDefaultTimeZoneType. Alternatively, you can change the initial
* default implementation type by setting a property below.
*
*
*
* #
* # The default TimeZone implementation type used by the ICU TimeZone
* # factory method. [ ICU | JDK ]
* #
* com.ibm.icu.util.TimeZone.DefaultTimeZoneType = ICU
*
*
*
* This property is included in ICUConfig.properties in com.ibm.icu package. When the
* TimeZone class is loaded, the initialization code checks if the property
* com.ibm.icu.util.TimeZone.DefaultTimeZoneType=xxx is defined by the system
* properties. If not available, then it loads ICUConfig.properties to get the default
* time zone implementation type. The property setting is only used for the initial
* default value and you can change the default type by calling
* setDefaultTimeZoneType at runtime.
*
* @see Calendar
* @see GregorianCalendar
* @see SimpleTimeZone
* @author Mark Davis, David Goldsmith, Chen-Lieh Huang, Alan Liu
* @stable ICU 2.0
*/
abstract public class TimeZone implements Serializable, Cloneable, Freezable {
/**
* Logger instance for this class
*/
private static final Logger LOGGER = Logger.getLogger("com.ibm.icu.util.TimeZone");
// using serialver from jdk1.4.2_05
private static final long serialVersionUID = -744942128318337471L;
/**
* Default constructor. (For invocation by subclass constructors,
* typically implicit.)
* @stable ICU 2.8
*/
public TimeZone() {
}
/**
* Constructing a TimeZone with the given time zone ID.
* @param ID the time zone ID.
* @internal
* @deprecated This API is ICU internal only.
*/
protected TimeZone(String ID) {
if (ID == null) {
throw new NullPointerException();
}
this.ID = ID;
}
/**
* {@icu} A time zone implementation type indicating ICU's own TimeZone used by
* getTimeZone, setDefaultTimeZoneType
* and getDefaultTimeZoneType.
* @stable ICU 4.0
*/
public static final int TIMEZONE_ICU = 0;
/**
* {@icu} A time zone implementation type indicating JDK TimeZone used by
* getTimeZone, setDefaultTimeZoneType
* and getDefaultTimeZoneType.
* @stable ICU 4.0
*/
public static final int TIMEZONE_JDK = 1;
/**
* A style specifier for getDisplayName() indicating
* a short name, such as "PST."
* @see #LONG
* @stable ICU 2.0
*/
public static final int SHORT = 0;
/**
* A style specifier for getDisplayName() indicating
* a long name, such as "Pacific Standard Time."
* @see #SHORT
* @stable ICU 2.0
*/
public static final int LONG = 1;
/**
* {@icu} A style specifier for getDisplayName() indicating
* a short generic name, such as "PT."
* @see #LONG_GENERIC
* @stable ICU 4.4
*/
public static final int SHORT_GENERIC = 2;
/**
* {@icu} A style specifier for getDisplayName() indicating
* a long generic name, such as "Pacific Time."
* @see #SHORT_GENERIC
* @stable ICU 4.4
*/
public static final int LONG_GENERIC = 3;
/**
* {@icu} A style specifier for getDisplayName() indicating
* a short name derived from the timezone's offset, such as "-0800."
* @see #LONG_GMT
* @stable ICU 4.4
*/
public static final int SHORT_GMT = 4;
/**
* {@icu} A style specifier for getDisplayName() indicating
* a long name derived from the timezone's offset, such as "GMT-08:00."
* @see #SHORT_GMT
* @stable ICU 4.4
*/
public static final int LONG_GMT = 5;
/**
* {@icu} A style specifier for getDisplayName() indicating
* a short name derived from the timezone's short standard or daylight
* timezone name ignoring commonlyUsed, such as "PDT."
* @stable ICU 4.4
*/
public static final int SHORT_COMMONLY_USED = 6;
/**
* {@icu} A style specifier for getDisplayName() indicating
* a long name derived from the timezone's fallback name, such as
* "United States (Los Angeles)."
* @stable ICU 4.4
*/
public static final int GENERIC_LOCATION = 7;
/**
* {@icu} The time zone ID reserved for unknown time zone.
* @see #getTimeZone(String)
*
* @stable ICU 4.8
*/
public static final String UNKNOWN_ZONE_ID = "Etc/Unknown";
/**
* The canonical ID for GMT(UTC) time zone.
*/
static final String GMT_ZONE_ID = "Etc/GMT";
/**
* {@icu} The immutable (frozen) "unknown" time zone.
* It behaves like the GMT/UTC time zone but has the UNKNOWN_ZONE_ID = "Etc/Unknown".
* {@link TimeZone#getTimeZone(String)} returns a mutable clone of this
* time zone if the input ID is not recognized.
*
* @see #UNKNOWN_ZONE_ID
* @see #getTimeZone(String)
*
* @draft ICU 49
* @provisional This API might change or be removed in a future release.
*/
public static final TimeZone UNKNOWN_ZONE = new SimpleTimeZone(0, UNKNOWN_ZONE_ID).freeze();
/**
* {@icu} The immutable GMT (=UTC) time zone. Its ID is "Etc/GMT".
*
* @draft ICU 49
* @provisional This API might change or be removed in a future release.
*/
public static final TimeZone GMT_ZONE = new SimpleTimeZone(0, GMT_ZONE_ID).freeze();
/**
* {@icu} System time zone type constants used by filtering zones in
* {@link TimeZone#getAvailableIDs(SystemTimeZoneType, String, Integer)}
*
* @stable ICU 4.8
*/
public enum SystemTimeZoneType {
/**
* Any system zones.
* @stable ICU 4.8
* @provisional This API might change or be removed in a future release.
*/
ANY,
/**
* Canonical system zones.
* @stable ICU 4.8
* @provisional This API might change or be removed in a future release.
*/
CANONICAL,
/**
* Canonical system zones associated with actual locations.
* @stable ICU 4.8
* @provisional This API might change or be removed in a future release.
*/
CANONICAL_LOCATION,
}
/**
* 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.
* @param era the era of the given date.
* @param year the year in the given date.
* @param month the month in the given date.
* Month is 0-based. e.g., 0 for January.
* @param day the day-in-month of the given date.
* @param dayOfWeek the day-of-week of the given date.
* @param milliseconds the millis in day in standard local time.
* @return the offset to add *to* GMT to get local time.
* @stable ICU 2.0
*/
abstract public int getOffset(int era, int year, int month, int day,
int dayOfWeek, int milliseconds);
/**
* 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.
*
* @param date the date represented in milliseconds since January 1, 1970 00:00:00 GMT
* @return the amount of time in milliseconds to add to UTC to get local time.
*
* @see Calendar#ZONE_OFFSET
* @see Calendar#DST_OFFSET
* @see #getOffset(long, boolean, int[])
* @stable ICU 2.8
*/
public int getOffset(long date) {
int[] result = new int[2];
getOffset(date, false, result);
return result[0]+result[1];
}
/**
* Returns the time zone raw and GMT offset for the given moment
* in time. Upon return, local-millis = GMT-millis + rawOffset +
* dstOffset. All computations are performed in the proleptic
* Gregorian calendar. The default implementation in the TimeZone
* class delegates to the 8-argument getOffset().
*
* @param date moment in time for which to return offsets, in
* units of milliseconds from January 1, 1970 0:00 GMT, either GMT
* time or local wall time, depending on `local'.
* @param local if true, `date' is local wall time; otherwise it
* is in GMT time.
* @param offsets output parameter to receive the raw offset, that
* is, the offset not including DST adjustments, in offsets[0],
* and the DST offset, that is, the offset to be added to
* `rawOffset' to obtain the total offset between local and GMT
* time, in offsets[1]. If DST is not in effect, the DST offset is
* zero; otherwise it is a positive value, typically one hour.
*
* @stable ICU 2.8
*/
public void getOffset(long date, boolean local, int[] offsets) {
offsets[0] = getRawOffset();
if (!local) {
date += offsets[0]; // now in local standard millis
}
// When local == true, date might not be in local standard
// millis. getOffset taking 6 parameters used here assume
// the given time in day is local standard time.
// At STD->DST transition, there is a range of time which
// does not exist. When 'date' is in this time range
// (and local == true), this method interprets the specified
// local time as DST. At DST->STD transition, there is a
// range of time which occurs twice. In this case, this
// method interprets the specified local time as STD.
// To support the behavior above, we need to call getOffset
// (with 6 args) twice when local == true and DST is
// detected in the initial call.
int fields[] = new int[6];
for (int pass = 0; ; pass++) {
Grego.timeToFields(date, fields);
offsets[1] = getOffset(GregorianCalendar.AD,
fields[0], fields[1], fields[2],
fields[3], fields[5]) - offsets[0];
if (pass != 0 || !local || offsets[1] == 0) {
break;
}
// adjust to local standard millis
date -= offsets[1];
}
}
/**
* Sets the base time zone offset to GMT.
* This is the offset to add *to* UTC to get local time.
* @param offsetMillis the given base time zone offset to GMT.
* @stable ICU 2.0
*/
abstract public void setRawOffset(int offsetMillis);
/**
* Gets unmodified offset, NOT modified in case of daylight savings.
* This is the offset to add *to* UTC to get local time.
* @return the unmodified offset to add *to* UTC to get local time.
* @stable ICU 2.0
*/
abstract public int getRawOffset();
/**
* Gets the ID of this time zone.
* @return the ID of this time zone.
* @stable ICU 2.0
*/
public String getID() {
return ID;
}
/**
* Sets the time zone ID. This does not change any other data in
* the time zone object.
* @param ID the new time zone ID.
* @stable ICU 2.0
*/
public void setID(String ID) {
if (ID == null) {
throw new NullPointerException();
}
if (isFrozen()) {
throw new UnsupportedOperationException("Attempt to modify a frozen TimeZone instance.");
}
this.ID = ID;
}
/**
* Returns a name of this time zone suitable for presentation to the user
* in the default DISPLAY locale.
* This method returns the long generic name.
* If the display name is not available for the locale,
* a fallback based on the country, city, or time zone id will be used.
* @return the human-readable name of this time zone in the default locale.
* @see Category#DISPLAY
* @stable ICU 2.0
*/
public final String getDisplayName() {
return _getDisplayName(LONG_GENERIC, false, ULocale.getDefault(Category.DISPLAY));
}
/**
* Returns a name of this time zone suitable for presentation to the user
* in the specified locale.
* This method returns the long generic name.
* If the display name is not available for the locale,
* a fallback based on the country, city, or time zone id will be used.
* @param locale the locale in which to supply the display name.
* @return the human-readable name of this time zone in the given locale
* or in the default locale if the given locale is not recognized.
* @stable ICU 2.0
*/
public final String getDisplayName(Locale locale) {
return _getDisplayName(LONG_GENERIC, false, ULocale.forLocale(locale));
}
/**
* 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,
* a fallback based on the country, city, or time zone id will be used.
* @param locale the ulocale in which to supply the display name.
* @return the human-readable name of this time zone in the given locale
* or in the default ulocale if the given ulocale is not recognized.
* @stable ICU 3.2
*/
public final String getDisplayName(ULocale locale) {
return _getDisplayName(LONG_GENERIC, false, locale);
}
/**
* Returns a name of this time zone suitable for presentation to the user
* in the default DISPLAY locale.
* If the display name is not available for the locale,
* then this method returns a string in the localized GMT offset format
* such as GMT[+-]HH:mm.
* @param daylight if true, return the daylight savings name.
* @param style the output style of the display name. Valid styles are
* SHORT, LONG, SHORT_GENERIC,
* LONG_GENERIC, SHORT_GMT, LONG_GMT,
* SHORT_COMMONLY_USED or GENERIC_LOCATION.
* @return the human-readable name of this time zone in the default locale.
* @see Category#DISPLAY
* @stable ICU 2.0
*/
public final String getDisplayName(boolean daylight, int style) {
return getDisplayName(daylight, style, ULocale.getDefault(Category.DISPLAY));
}
/**
* 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 localized GMT offset format
* such as GMT[+-]HH:mm.
* @param daylight if true, return the daylight savings name.
* @param style the output style of the display name. Valid styles are
* SHORT, LONG, SHORT_GENERIC,
* LONG_GENERIC, SHORT_GMT, LONG_GMT,
* SHORT_COMMONLY_USED or GENERIC_LOCATION.
* @param locale the locale in which to supply the display name.
* @return the human-readable name of this time zone in the given locale
* or in the default locale if the given locale is not recognized.
* @exception IllegalArgumentException style is invalid.
* @stable ICU 2.0
*/
public String getDisplayName(boolean daylight, int style, Locale locale) {
return getDisplayName(daylight, style, ULocale.forLocale(locale));
}
/**
* 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 localized GMT offset format
* such as GMT[+-]HH:mm.
* @param daylight if true, return the daylight savings name.
* @param style the output style of the display name. Valid styles are
* SHORT, LONG, SHORT_GENERIC,
* LONG_GENERIC, SHORT_GMT, LONG_GMT,
* SHORT_COMMONLY_USED or GENERIC_LOCATION.
* @param locale the locale in which to supply the display name.
* @return the human-readable name of this time zone in the given locale
* or in the default locale if the given locale is not recognized.
* @exception IllegalArgumentException style is invalid.
* @stable ICU 3.2
*/
public String getDisplayName(boolean daylight, int style, ULocale locale) {
if (style < SHORT || style > GENERIC_LOCATION) {
throw new IllegalArgumentException("Illegal style: " + style);
}
return _getDisplayName(style, daylight, locale);
}
/**
* internal version (which is called by public APIs) accepts
* SHORT, LONG, SHORT_GENERIC, LONG_GENERIC, SHORT_GMT, LONG_GMT,
* SHORT_COMMONLY_USED and GENERIC_LOCATION.
*/
private String _getDisplayName(int style, boolean daylight, ULocale locale) {
if (locale == null) {
throw new NullPointerException("locale is null");
}
String result = null;
if (style == GENERIC_LOCATION || style == LONG_GENERIC || style == SHORT_GENERIC) {
// Generic format
TimeZoneFormat tzfmt = TimeZoneFormat.getInstance(locale);
long date = System.currentTimeMillis();
Output timeType = new Output(TimeType.UNKNOWN);
switch (style) {
case GENERIC_LOCATION:
result = tzfmt.format(Style.GENERIC_LOCATION, this, date, timeType);
break;
case LONG_GENERIC:
result = tzfmt.format(Style.GENERIC_LONG, this, date, timeType);
break;
case SHORT_GENERIC:
result = tzfmt.format(Style.GENERIC_SHORT, this, date, timeType);
break;
}
// Generic format many use Localized GMT as the final fallback.
// When Localized GMT format is used, the result might not be
// appropriate for the requested daylight value.
if (daylight && timeType.value == TimeType.STANDARD ||
!daylight && timeType.value == TimeType.DAYLIGHT) {
int offset = daylight ? getRawOffset() + getDSTSavings() : getRawOffset();
result = tzfmt.formatOffsetLocalizedGMT(offset);
}
} else if (style == LONG_GMT || style == SHORT_GMT) {
// Offset format
TimeZoneFormat tzfmt = TimeZoneFormat.getInstance(locale);
int offset = daylight && useDaylightTime() ? getRawOffset() + getDSTSavings() : getRawOffset();
switch (style) {
case LONG_GMT:
result = tzfmt.formatOffsetLocalizedGMT(offset);
break;
case SHORT_GMT:
result = tzfmt.formatOffsetRFC822(offset);
break;
}
} else {
// Specific format
assert(style == LONG || style == SHORT || style == SHORT_COMMONLY_USED);
// Gets the name directly from TimeZoneNames
long date = System.currentTimeMillis();
TimeZoneNames tznames = TimeZoneNames.getInstance(locale);
NameType nameType = null;
switch (style) {
case LONG:
nameType = daylight ? NameType.LONG_DAYLIGHT : NameType.LONG_STANDARD;
break;
case SHORT:
case SHORT_COMMONLY_USED:
nameType = daylight ? NameType.SHORT_DAYLIGHT : NameType.SHORT_STANDARD;
break;
}
result = tznames.getDisplayName(ZoneMeta.getCanonicalCLDRID(this), nameType, date);
if (result == null) {
// Fallback to localized GMT
TimeZoneFormat tzfmt = TimeZoneFormat.getInstance(locale);
int offset = daylight && useDaylightTime() ? getRawOffset() + getDSTSavings() : getRawOffset();
result = tzfmt.formatOffsetLocalizedGMT(offset);
}
}
assert(result != null);
return result;
}
/**
* 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.
*
* @return the amount of saving time in milliseconds
* @stable ICU 2.8
*/
public int getDSTSavings() {
if (useDaylightTime()) {
return 3600000;
}
return 0;
}
/**
* Queries if this time zone uses daylight savings time.
* @return 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 returns true
* when the time zone uses daylight savings time in the current
* (Gregorian) calendar year.
* @stable ICU 2.0
*/
abstract public boolean useDaylightTime();
/**
* 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 if {@link #useDaylightTime()}
* or {@link #inDaylightTime(Date) inDaylightTime(new Date())} returns true.
*
* Note: This method was added for JDK compatibility support.
* The JDK's useDaylightTime() only checks the last known rule(s), therefore
* it may return false even the zone observes daylight saving time currently. JDK added
* observesDaylightTime() to resolve the issue. In ICU, {@link #useDaylightTime()}
* works differently. The ICU implementation checks if the zone uses daylight saving time
* in the current calendar year. Therefore, it will never return false if
* daylight saving time is currently used.
*
* ICU's TimeZone subclass implementations override this method to support the same behavior
* with JDK's observesDaylightSavingTime(). Unlike {@link #useDaylightTime()},
* the implementation does not take past daylight saving time into account, so
* that this method may return false even when {@link #useDaylightTime()} returns
* true.
*
* @return true if this time zone is in daylight saving time or will observe
* daylight saving time at any future time.
* @see #useDaylightTime
* @stable ICU 49
*/
public boolean observesDaylightTime() {
return useDaylightTime() || inDaylightTime(new Date());
}
/**
* Queries if the given date is in daylight savings time in
* this time zone.
* @param date the given Date.
* @return true if the given date is in daylight savings time,
* false, otherwise.
* @stable ICU 2.0
*/
abstract public boolean inDaylightTime(Date date);
/**
* Gets the TimeZone for the given ID.
*
* @param ID the ID for a TimeZone, such as "America/Los_Angeles",
* or a custom ID such as "GMT-8:00". Note that the support of abbreviations,
* such as "PST", is for JDK 1.1.x compatibility only and full names should be used.
*
* @return the specified TimeZone, or a mutable clone of the UNKNOWN_ZONE
* if the given ID cannot be understood or if the given ID is "Etc/Unknown".
* @see #UNKNOWN_ZONE
* @stable ICU 2.0
*/
public static TimeZone getTimeZone(String ID) {
return getTimeZone(ID, TZ_IMPL, false);
}
/**
* Gets the TimeZone for the given ID. The instance of TimeZone
* returned by this method is immutable. Any methods mutate the instance({@link #setID(String)},
* {@link #setRawOffset(int)}) will throw UnsupportedOperationException upon its
* invocation.
*
* @param ID the ID for a TimeZone, such as "America/Los_Angeles",
* or a custom ID such as "GMT-8:00". Note that the support of abbreviations,
* such as "PST", is for JDK 1.1.x compatibility only and full names should be used.
*
* @return the specified TimeZone, or the UNKNOWN_ZONE
* if the given ID cannot be understood.
* @see #UNKNOWN_ZONE
* @draft ICU 49
* @provisional This API might change or be removed in a future release.
*/
public static TimeZone getFrozenTimeZone(String ID) {
return getTimeZone(ID, TZ_IMPL, true);
}
/**
* Gets the TimeZone for the given ID and the timezone type.
* @param ID the ID for a TimeZone, such as "America/Los_Angeles", or a
* custom ID such as "GMT-8:00". Note that the support of abbreviations, such as
* "PST", is for JDK 1.1.x compatibility only and full names should be used.
* @param type Time zone type, either TIMEZONE_ICU or
* TIMEZONE_JDK.
* @return the specified TimeZone, or a mutable clone of the UNKNOWN_ZONE if the given ID
* cannot be understood or if the given ID is "Etc/Unknown".
* @see #UNKNOWN_ZONE
* @stable ICU 4.0
*/
public static TimeZone getTimeZone(String ID, int type) {
return getTimeZone(ID, type, false);
}
/**
* Gets the TimeZone for the given ID and the timezone type.
* @param ID time zone ID
* @param type time zone implementation type, TIMEZONE_JDK or TIMEZONE_ICU
* @param frozen specify if the returned object can be frozen
* @return the specified TimeZone or UNKNOWN_ZONE if the given ID
* cannot be understood.
*/
private static synchronized TimeZone getTimeZone(String ID, int type, boolean frozen) {
TimeZone result;
if (type == TIMEZONE_JDK) {
result = JavaTimeZone.createTimeZone(ID);
if (result != null) {
return frozen ? result.freeze() : result;
}
} else {
/* We first try to lookup the zone ID in our system list. If this
* fails, we try to parse it as a custom string GMT[+-]HH:mm. If
* all else fails, we return GMT, which is probably not what the
* user wants, but at least is a functioning TimeZone object.
*
* We cannot return NULL, because that would break compatibility
* with the JDK.
*/
if(ID==null){
throw new NullPointerException();
}
result = ZoneMeta.getSystemTimeZone(ID);
}
if (result == null) {
result = ZoneMeta.getCustomTimeZone(ID);
}
if (result == null) {
LOGGER.fine("\"" +ID + "\" is a bogus id so timezone is falling back to Etc/Unknown(GMT).");
result = UNKNOWN_ZONE;
}
return frozen ? result : result.cloneAsThawed();
}
/**
* Sets the default time zone type used by getTimeZone.
* @param type time zone type, either TIMEZONE_ICU or
* TIMEZONE_JDK.
* @stable ICU 4.0
*/
public static synchronized void setDefaultTimeZoneType(int type) {
if (type != TIMEZONE_ICU && type != TIMEZONE_JDK) {
throw new IllegalArgumentException("Invalid timezone type");
}
TZ_IMPL = type;
}
/**
* {@icu} Returns the default time zone type currently used.
* @return The default time zone type, either TIMEZONE_ICU or
* TIMEZONE_JDK.
* @stable ICU 4.0
*/
public static int getDefaultTimeZoneType() {
return TZ_IMPL;
}
/**
* {@icu} Returns a set of time zone ID strings with the given filter conditions.
*
Note:A Set returned by this method is
* immutable.
* @param zoneType The system time zone type.
* @param region The ISO 3166 two-letter country code or UN M.49 three-digit area code.
* When null, no filtering done by region.
* @param rawOffset An offset from GMT in milliseconds, ignoring the effect of daylight savings
* time, if any. When null, no filtering done by zone offset.
* @return an immutable set of system time zone IDs.
* @see SystemTimeZoneType
*
* @stable ICU 4.8
*/
public static Set getAvailableIDs(SystemTimeZoneType zoneType,
String region, Integer rawOffset) {
return ZoneMeta.getAvailableIDs(zoneType, region, rawOffset);
}
/**
* Return a new String array containing all system TimeZone IDs
* with the given raw offset from GMT. These IDs may be passed to
* get() to construct the corresponding TimeZone
* object.
* @param rawOffset the offset in milliseconds from GMT
* @return an array of IDs for system TimeZones with the given
* raw offset. If there are none, return a zero-length array.
* @see #getAvailableIDs(SystemTimeZoneType, String, Integer)
*
* @stable ICU 2.0
*/
public static String[] getAvailableIDs(int rawOffset) {
Set ids = getAvailableIDs(SystemTimeZoneType.ANY, null, Integer.valueOf(rawOffset));
return ids.toArray(new String[0]);
}
/**
* Return a new String array containing all system TimeZone IDs
* associated with the given country. These IDs may be passed to
* get() to construct the corresponding TimeZone
* object.
* @param country a two-letter ISO 3166 country code, or null
* to return zones not associated with any country
* @return an array of IDs for system TimeZones in the given
* country. If there are none, return a zero-length array.
* @see #getAvailableIDs(SystemTimeZoneType, String, Integer)
*
* @stable ICU 2.0
*/
public static String[] getAvailableIDs(String country) {
Set ids = getAvailableIDs(SystemTimeZoneType.ANY, country, null);
return ids.toArray(new String[0]);
}
/**
* Return a new String array containing all system TimeZone IDs.
* These IDs (and only these IDs) may be passed to
* get() to construct the corresponding TimeZone
* object.
* @return an array of all system TimeZone IDs
* @see #getAvailableIDs(SystemTimeZoneType, String, Integer)
*
* @stable ICU 2.0
*/
public static String[] getAvailableIDs() {
Set ids = getAvailableIDs(SystemTimeZoneType.ANY, null, null);
return ids.toArray(new String[0]);
}
/**
* {@icu} Returns the number of IDs in the equivalency group that
* includes the given ID. An equivalency group contains zones
* that have the same GMT offset and rules.
*
* The returned count includes the given ID; it is always >= 1
* for valid IDs. The given ID must be a system time zone. If it
* is not, returns zero.
* @param id a system time zone ID
* @return the number of zones in the equivalency group containing
* 'id', or zero if 'id' is not a valid system ID
* @see #getEquivalentID
* @stable ICU 2.0
*/
public static int countEquivalentIDs(String id) {
return ZoneMeta.countEquivalentIDs(id);
}
/**
* Returns an ID in the equivalency group that
* includes the given ID. An equivalency group contains zones
* that have the same GMT offset and rules.
*
*
The given index must be in the range 0..n-1, where n is the
* value returned by countEquivalentIDs(id). For
* some value of 'index', the returned value will be equal to the
* given id. If the given id is not a valid system time zone, or
* if 'index' is out of range, then returns an empty string.
* @param id a system time zone ID
* @param index a value from 0 to n-1, where n is the value
* returned by countEquivalentIDs(id)
* @return the ID of the index-th zone in the equivalency group
* containing 'id', or an empty string if 'id' is not a valid
* system ID or 'index' is out of range
* @see #countEquivalentIDs
* @stable ICU 2.0
*/
public static String getEquivalentID(String id, int index) {
return ZoneMeta.getEquivalentID(id, index);
}
/**
* Gets the default TimeZone for this host.
* The source of the default TimeZone
* may vary with implementation.
* @return a default TimeZone.
* @stable ICU 2.0
*/
public static synchronized TimeZone getDefault() {
if (defaultZone == null) {
if (TZ_IMPL == TIMEZONE_JDK) {
defaultZone = new JavaTimeZone();
} else {
java.util.TimeZone temp = java.util.TimeZone.getDefault();
defaultZone = getFrozenTimeZone(temp.getID());
}
}
return defaultZone.cloneAsThawed();
}
/**
* 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.
* @param tz the new default time zone
* @stable ICU 2.0
*/
public static synchronized void setDefault(TimeZone tz) {
defaultZone = tz;
java.util.TimeZone jdkZone = null;
if (defaultZone instanceof JavaTimeZone) {
jdkZone = ((JavaTimeZone)defaultZone).unwrap();
} else {
// Keep java.util.TimeZone default in sync so java.util.Date
// can interoperate with com.ibm.icu.util classes.
if (tz != null) {
if (tz instanceof com.ibm.icu.impl.OlsonTimeZone) {
// Because of the lack of APIs supporting historic
// zone offset/dst saving in JDK TimeZone,
// wrapping ICU TimeZone with JDK TimeZone will
// cause historic offset calculation in Calendar/Date.
// JDK calendar implementation calls getRawOffset() and
// getDSTSavings() when the instance of JDK TimeZone
// is not an instance of JDK internal TimeZone subclass
// (sun.util.calendar.ZoneInfo). Ticket#6459
String icuID = tz.getID();
jdkZone = java.util.TimeZone.getTimeZone(icuID);
if (!icuID.equals(jdkZone.getID())) {
// JDK does not know the ID..
jdkZone = null;
}
}
if (jdkZone == null) {
jdkZone = TimeZoneAdapter.wrap(tz);
}
}
}
java.util.TimeZone.setDefault(jdkZone);
}
/**
* 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.
* @param other the TimeZone object to be compared with
* @return true if the other zone is not null and is the same as this one,
* with the possible exception of the ID
* @stable ICU 2.0
*/
public boolean hasSameRules(TimeZone other) {
return other != null &&
getRawOffset() == other.getRawOffset() &&
useDaylightTime() == other.useDaylightTime();
}
/**
* Overrides clone.
* @stable ICU 2.0
*/
public Object clone() {
if (isFrozen()) {
return this;
}
return cloneAsThawed();
}
/**
* Overrides equals.
* @stable ICU 3.6
*/
public boolean equals(Object obj){
if (this == obj) return true;
if (obj == null || getClass() != obj.getClass()) return false;
return (ID.equals(((TimeZone)obj).ID));
}
/**
* Overrides hashCode.
* @stable ICU 3.6
*/
public int hashCode(){
return ID.hashCode();
}
/**
* {@icu} Returns the time zone data version currently used by ICU.
*
* @return the version string, such as "2007f"
* @throws MissingResourceException if ICU time zone resource bundle
* is missing or the version information is not available.
*
* @stable ICU 3.8
*/
public static synchronized String getTZDataVersion() {
if (TZDATA_VERSION == null) {
UResourceBundle tzbundle = UResourceBundle.getBundleInstance(
"com/ibm/icu/impl/data/icudt" + VersionInfo.ICU_DATA_VERSION_PATH, "zoneinfo64");
TZDATA_VERSION = tzbundle.getString("TZVersion");
}
return TZDATA_VERSION;
}
/**
* {@icu} Returns the canonical system time zone ID or the normalized
* custom time zone ID for the given time zone ID.
* @param id The input time zone ID to be canonicalized.
* @return The canonical system time zone ID or the custom time zone ID
* in normalized format for the given time zone ID. When the given time zone ID
* is neither a known system time zone ID nor a valid custom time zone ID,
* null is returned.
* @stable ICU 4.0
*/
public static String getCanonicalID(String id) {
return getCanonicalID(id, null);
}
/**
* {@icu} Returns the canonical system time zone ID or the normalized
* custom time zone ID for the given time zone ID.
* @param id The input time zone ID to be canonicalized.
* @param isSystemID When non-null boolean array is specified and
* the given ID is a known system time zone ID, true is set to isSystemID[0]
* @return The canonical system time zone ID or the custom time zone ID
* in normalized format for the given time zone ID. When the given time zone ID
* is neither a known system time zone ID nor a valid custom time zone ID,
* null is returned.
* @stable ICU 4.0
*/
public static String getCanonicalID(String id, boolean[] isSystemID) {
String canonicalID = null;
boolean systemTzid = false;
if (id != null && id.length() != 0) {
if (id.equals(TimeZone.UNKNOWN_ZONE_ID)) {
// special case - Etc/Unknown is a canonical ID, but not system ID
canonicalID = TimeZone.UNKNOWN_ZONE_ID;
systemTzid = false;
} else {
canonicalID = ZoneMeta.getCanonicalCLDRID(id);
if (canonicalID != null) {
systemTzid = true;
} else {
canonicalID = ZoneMeta.getCustomID(id);
}
}
}
if (isSystemID != null) {
isSystemID[0] = systemTzid;
}
return canonicalID;
}
/**
* {@icu} Returns the region code associated with the given
* system time zone ID. The region code is either ISO 3166
* 2-letter country code or UN M.49 3-digit area code.
* When the time zone is not associated with a specific location,
* for example - "Etc/UTC", "EST5EDT", then this method returns
* "001" (UN M.49 area code for World).
* @param id the system time zone ID.
* @return the region code associated with the given
* system time zone ID.
* @throws IllegalArgumentException if id is not a known system ID.
* @see #getAvailableIDs(String)
*
* @stable ICU 4.8
*/
public static String getRegion(String id) {
String region = null;
// "Etc/Unknown" is not a system time zone ID,
// but in the zone data.
if (!id.equals(UNKNOWN_ZONE_ID)) {
region = ZoneMeta.getRegion(id);
}
if (region == null) {
// unknown id
throw new IllegalArgumentException("Unknown system zone id: " + id);
}
return region;
}
// Freezable stuffs
/**
* {@inheritDoc}
* @draft ICU 49
* @provisional This API might change or be removed in a future release.
*/
public boolean isFrozen() {
return false;
}
/**
* {@inheritDoc}
* @draft ICU 49
* @provisional This API might change or be removed in a future release.
*/
public TimeZone freeze() {
throw new UnsupportedOperationException("Needs to be implemented by the subclass.");
}
/**
* {@inheritDoc}
* @draft ICU 49
* @provisional This API might change or be removed in a future release.
*/
public TimeZone cloneAsThawed() {
try {
TimeZone other = (TimeZone) super.clone();
return other;
} catch (CloneNotSupportedException e) {
throw new RuntimeException(e);
}
}
// =======================privates===============================
/**
* 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.
* @serial
*/
private String ID;
/**
* The default time zone, or null if not set.
*/
private static TimeZone defaultZone = null;
/**
* The tzdata version
*/
private static String TZDATA_VERSION = null;
/**
* TimeZone implementation type
*/
private static int TZ_IMPL = TIMEZONE_ICU;
/**
* TimeZone implementation type initialization
*/
private static final String TZIMPL_CONFIG_KEY = "com.ibm.icu.util.TimeZone.DefaultTimeZoneType";
private static final String TZIMPL_CONFIG_ICU = "ICU";
private static final String TZIMPL_CONFIG_JDK = "JDK";
static {
String type = ICUConfig.get(TZIMPL_CONFIG_KEY, TZIMPL_CONFIG_ICU);
if (type.equalsIgnoreCase(TZIMPL_CONFIG_JDK)) {
TZ_IMPL = TIMEZONE_JDK;
}
}
}
//eof