Also see:

LONG
since: 1.2 -

Also see:

SHORT
since: 1.2 -

 public TimeZone() 
{

}

Sole constructor. (For invocation by subclass constructors, typically implicit.)

 public Object clone() 
{
        try {
            TimeZone other = (TimeZone) super.clone();
            other.ID = ID;
            return other;
        } catch (CloneNotSupportedException e) {
            throw new InternalError();
        }
}

Creates a copy of this TimeZone.

 public static synchronized String[] getAvailableIDs() 
{
        return ZoneInfo.getAvailableIDs();
}

Gets all the available IDs supported.

 public static synchronized String[] getAvailableIDs(int rawOffset) 
{
        return ZoneInfo.getAvailableIDs(rawOffset);
}

Gets the available IDs according to the given time zone offset in milliseconds.

 public int getDSTSavings() 
{
        if (useDaylightTime()) {
            return 3600000;
        }
        return 0;
}

Returns the amount of time to be added to local standard time to get local wall clock time.

The default implementation returns 3600000 milliseconds (i.e., one hour) if a call to #useDaylightTime() returns {@code true}. Otherwise, 0 (zero) is returned.

If an underlying {@code TimeZone} implementation subclass supports historical and future Daylight Saving Time schedule changes, this method returns the amount of saving time of the last known Daylight Saving Time rule that can be a future prediction.

If the amount of saving time at any given time stamp is required, construct a Calendar with this {@code TimeZone} and the time stamp, and call Calendar.get {@code (}Calendar#DST_OFFSET {@code )}.

 public static TimeZone getDefault() 
{
        return (TimeZone) getDefaultRef().clone();
}

Gets the default TimeZone for this host. The source of the default TimeZone may vary with implementation.

 static TimeZone getDefaultRef() 
{
        TimeZone defaultZone = defaultZoneTL.get();
        if (defaultZone == null) {
            defaultZone = defaultTimeZone;
            if (defaultZone == null) {
                // Need to initialize the default time zone.
                defaultZone = setDefaultZone();
                assert defaultZone != null;
            }
        }
        // Don't clone here.
        return defaultZone;
}

Returns the reference to the default TimeZone object. This method doesn't create a clone.

 public final String getDisplayName() 
{
        return getDisplayName(false, LONG,
                              Locale.getDefault(Locale.Category.DISPLAY));
}

Returns a long standard time name of this {@code TimeZone} suitable for presentation to the user in the default locale.

This method is equivalent to:

getDisplayName(false, #LONG ,
               Locale.getDefault(Locale.Category#DISPLAY ))

 public final String getDisplayName(Locale locale) 
{
        return getDisplayName(false, LONG, locale);
}

Returns a long standard time name of this {@code TimeZone} suitable for presentation to the user in the specified {@code locale}.

This method is equivalent to:

getDisplayName(false, #LONG , locale)

 public final String getDisplayName(boolean daylight,
    int style) 
{
        return getDisplayName(daylight, style,
                              Locale.getDefault(Locale.Category.DISPLAY));
}

Returns a name in the specified {@code style} of this {@code TimeZone} suitable for presentation to the user in the default locale. If the specified {@code daylight} is {@code true}, a Daylight Saving Time name is returned (even if this {@code TimeZone} doesn't observe Daylight Saving Time). Otherwise, a Standard Time name is returned.

This method is equivalent to:

getDisplayName(daylight, style,
               Locale.getDefault(Locale.Category#DISPLAY ))

 public String getDisplayName(boolean daylight,
    int style,
    Locale locale) 
{
        if (style != SHORT && style != LONG) {
            throw new IllegalArgumentException("Illegal style: " + style);
        }
        String id = getID();
        String[] names = getDisplayNames(id, locale);
        if (names == null) {
            if (id.startsWith("GMT")) {
                char sign = id.charAt(3);
                if (sign == '+' || sign == '-') {
                    return id;
                }
            }
            int offset = getRawOffset();
            if (daylight) {
                offset += getDSTSavings();
            }
            return ZoneInfoFile.toCustomID(offset);
        }
        int index = daylight ? 3 : 1;
        if (style == SHORT) {
            index++;
        }
        return names[index];
}

Returns a name in the specified {@code style} of this {@code TimeZone} suitable for presentation to the user in the specified {@code locale}. If the specified {@code daylight} is {@code true}, a Daylight Saving Time name is returned (even if this {@code TimeZone} doesn't observe Daylight Saving Time). Otherwise, a Standard Time name is returned.

When looking up a time zone name, the {@linkplain ResourceBundle.Control#getCandidateLocales(String,Locale) default Locale search path of ResourceBundle} derived from the specified {@code locale} is used. (No {@linkplain ResourceBundle.Control#getFallbackLocale(String,Locale) fallback Locale} search is performed.) If a time zone name in any {@code Locale} of the search path, including Locale#ROOT , is found, the name is returned. Otherwise, a string in the normalized custom ID format is returned.

 public String getID() 
{
        return ID;
}

Gets the ID of this time zone.

 public int getOffset(long date) 
{
        if (inDaylightTime(new Date(date))) {
            return getRawOffset() + getDSTSavings();
        }
        return getRawOffset();
}

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.

 abstract public int getOffset(int era,
    int year,
    int month,
    int day,
    int dayOfWeek,
    int milliseconds)
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.

 int getOffsets(long date,
    int[] offsets) 
{
        int rawoffset = getRawOffset();
        int dstoffset = 0;
        if (inDaylightTime(new Date(date))) {
            dstoffset = getDSTSavings();
        }
        if (offsets != null) {
            offsets[0] = rawoffset;
            offsets[1] = dstoffset;
        }
        return rawoffset + dstoffset;
}

Gets the raw GMT offset and the amount of daylight saving of this time zone at the given time.

 abstract public int getRawOffset()
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).

 public static synchronized TimeZone getTimeZone(String ID) 
{
        return getTimeZone(ID, true);
}

Gets the TimeZone for the given ID.

 public boolean hasSameRules(TimeZone other) 
{
        return other != null && getRawOffset() == other.getRawOffset() &&
            useDaylightTime() == other.useDaylightTime();
}

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.

 abstract public boolean inDaylightTime(Date date)
Queries if the given {@code date} is in Daylight Saving Time in
this time zone.

 public boolean observesDaylightTime() 
{
        return useDaylightTime() || inDaylightTime(new Date());
}

Returns {@code true} if this {@code TimeZone} is currently in Daylight Saving Time, or if a transition from Standard Time to Daylight Saving Time occurs at any future time.

The default implementation returns {@code true} if {@code useDaylightTime()} or {@code inDaylightTime(new Date())} returns {@code true}.

 public static  void setDefault(TimeZone zone) 
{
        if (hasPermission()) {
            synchronized (TimeZone.class) {
                defaultTimeZone = zone;
                defaultZoneTL.set(null);
            }
        } else {
            defaultZoneTL.set(zone);
        }
}

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.

 public  void setID(String ID) 
{
        if (ID == null) {
            throw new NullPointerException();
        }
        this.ID = ID;
}

Sets the time zone ID. This does not change any other data in the time zone object.

 abstract public  void setRawOffset(int offsetMillis)
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.

 abstract public boolean useDaylightTime()
Queries if this {@code TimeZone} uses Daylight Saving Time.

If an underlying {@code TimeZone} implementation subclass
supports historical and future Daylight Saving Time schedule
changes, this method refers to the last known Daylight Saving Time
rule that can be a future prediction and may not be the same as
the current rule. Consider calling #observesDaylightTime() 
if the current rule should also be taken into account.