Time zone offset java

Class TimeZone

Typically, you get a TimeZone using 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 getTimeZone 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 getAvailableIDs method to iterate through all the supported time zone IDs. 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 a custom time zone ID can be specified to produce a TimeZone. The syntax of a custom time zone ID is:

CustomID: GMT Sign Hours : Minutes GMT Sign Hours Minutes GMT Sign Hours Sign: one of + - Hours: Digit Digit Digit Minutes: Digit Digit Digit: one of 0 1 2 3 4 5 6 7 8 9 

Hours must be between 0 to 23 and Minutes must be between 00 to 59. For example, «GMT+10» and «GMT+0010» mean ten hours and ten minutes ahead of GMT, respectively.

The format is locale independent and digits must be taken from the Basic Latin block of the Unicode standard. No daylight saving time transition schedule can be specified with a custom time zone ID. If the specified string doesn’t match the syntax, «GMT» is used.

When creating a TimeZone , the specified custom time zone ID is normalized in the following syntax:

NormalizedCustomID: GMT Sign TwoDigitHours : Minutes Sign: one of + - TwoDigitHours: Digit Digit Minutes: Digit Digit Digit: one of 0 1 2 3 4 5 6 7 8 9 

Three-letter time zone IDs

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.

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Class ZoneOffset

A time-zone offset is the amount of time that a time-zone differs from Greenwich/UTC. This is usually a fixed number of hours and minutes.

Different parts of the world have different time-zone offsets. The rules for how offsets vary by place and time of year are captured in the ZoneId class.

For example, Paris is one hour ahead of Greenwich/UTC in winter and two hours ahead in summer. The ZoneId instance for Paris will reference two ZoneOffset instances — a +01:00 instance for winter, and a +02:00 instance for summer.

In 2008, time-zone offsets around the world extended from -12:00 to +14:00. To prevent any problems with that range being extended, yet still provide validation, the range of offsets is restricted to -18:00 to 18:00 inclusive.

This class is designed for use with the ISO calendar system. The fields of hours, minutes and seconds make assumptions that are valid for the standard ISO definitions of those fields. This class may be used with other calendar systems providing the definition of the time fields matches those of the ISO calendar system.

Instances of ZoneOffset must be compared using equals(java.lang.Object) . Implementations may choose to cache certain common offsets, however applications must not rely on such caching.

This is a value-based class; programmers should treat instances that are equal as interchangeable and should not use instances for synchronization, or unpredictable behavior may occur. For example, in a future release, synchronization may fail. The equals method should be used for comparisons.

Field Summary

Fields declared in class java.time.ZoneId

Method Summary

Methods declared in class java.time.ZoneId

Methods declared in class java.lang.Object

Field Details

UTC

MIN

MAX

Method Details

of

• Z — for UTC
• +h
• +hh
• +hh:mm
• -hh:mm
• +hhmm
• -hhmm
• +hh:mm:ss
• -hh:mm:ss
• +hhmmss
• -hhmmss

The ID of the returned offset will be normalized to one of the formats described by getId() .

The maximum supported range is from +18:00 to -18:00 inclusive.

ofHours

ofHoursMinutes

Obtains an instance of ZoneOffset using an offset in hours and minutes. The sign of the hours and minutes components must match. Thus, if the hours is negative, the minutes must be negative or zero. If the hours is zero, the minutes may be positive, negative or zero.

ofHoursMinutesSeconds

Obtains an instance of ZoneOffset using an offset in hours, minutes and seconds. The sign of the hours, minutes and seconds components must match. Thus, if the hours is negative, the minutes and seconds must be negative or zero.

from

Obtains an instance of ZoneOffset from a temporal object. This obtains an offset based on the specified temporal. A TemporalAccessor represents an arbitrary set of date and time information, which this factory converts to an instance of ZoneOffset . A TemporalAccessor represents some form of date and time information. This factory converts the arbitrary temporal object to an instance of ZoneOffset . The conversion uses the TemporalQueries.offset() query, which relies on extracting the OFFSET_SECONDS field. This method matches the signature of the functional interface TemporalQuery allowing it to be used as a query via method reference, ZoneOffset::from .

ofTotalSeconds

Obtains an instance of ZoneOffset specifying the total offset in seconds The offset must be in the range -18:00 to +18:00 , which corresponds to -64800 to +64800.

getTotalSeconds

Gets the total zone offset in seconds. This is the primary way to access the offset amount. It returns the total of the hours, minutes and seconds fields as a single offset that can be added to a time.

getId

• Z — for UTC (ISO-8601)
• +hh:mm or -hh:mm — if the seconds are zero (ISO-8601)
• +hh:mm:ss or -hh:mm:ss — if the seconds are non-zero (not ISO-8601)

getRules

Gets the associated time-zone rules. The rules will always return this offset when queried. The implementation class is immutable, thread-safe and serializable.

isSupported

Checks if the specified field is supported. This checks if this offset can be queried for the specified field. If false, then calling the range and get methods will throw an exception. If the field is a ChronoField then the query is implemented here. The OFFSET_SECONDS field returns true. All other ChronoField instances will return false. If the field is not a ChronoField , then the result of this method is obtained by invoking TemporalField.isSupportedBy(TemporalAccessor) passing this as the argument. Whether the field is supported is determined by the field.

range

Gets the range of valid values for the specified field. The range object expresses the minimum and maximum valid values for a field. This offset is used to enhance the accuracy of the returned range. If it is not possible to return the range, because the field is not supported or for some other reason, an exception is thrown. If the field is a ChronoField then the query is implemented here. The supported fields will return appropriate range instances. All other ChronoField instances will throw an UnsupportedTemporalTypeException . If the field is not a ChronoField , then the result of this method is obtained by invoking TemporalField.rangeRefinedBy(TemporalAccessor) passing this as the argument. Whether the range can be obtained is determined by the field.

get

Gets the value of the specified field from this offset as an int . This queries this offset for the value of the specified field. The returned value will always be within the valid range of values for the field. If it is not possible to return the value, because the field is not supported or for some other reason, an exception is thrown. If the field is a ChronoField then the query is implemented here. The OFFSET_SECONDS field returns the value of the offset. All other ChronoField instances will throw an UnsupportedTemporalTypeException . If the field is not a ChronoField , then the result of this method is obtained by invoking TemporalField.getFrom(TemporalAccessor) passing this as the argument. Whether the value can be obtained, and what the value represents, is determined by the field.

getLong

Gets the value of the specified field from this offset as a long . This queries this offset for the value of the specified field. If it is not possible to return the value, because the field is not supported or for some other reason, an exception is thrown. If the field is a ChronoField then the query is implemented here. The OFFSET_SECONDS field returns the value of the offset. All other ChronoField instances will throw an UnsupportedTemporalTypeException . If the field is not a ChronoField , then the result of this method is obtained by invoking TemporalField.getFrom(TemporalAccessor) passing this as the argument. Whether the value can be obtained, and what the value represents, is determined by the field.

query

Queries this offset using the specified query. This queries this offset using the specified query strategy object. The TemporalQuery object defines the logic to be used to obtain the result. Read the documentation of the query to understand what the result of this method will be. The result of this method is obtained by invoking the TemporalQuery.queryFrom(TemporalAccessor) method on the specified query passing this as the argument.

adjustInto

Adjusts the specified temporal object to have the same offset as this object. This returns a temporal object of the same observable type as the input with the offset changed to be the same as this. The adjustment is equivalent to using Temporal.with(TemporalField, long) passing ChronoField.OFFSET_SECONDS as the field. In most cases, it is clearer to reverse the calling pattern by using Temporal.with(TemporalAdjuster) :

// these two lines are equivalent, but the second approach is recommended temporal = thisOffset.adjustInto(temporal); temporal = temporal.with(thisOffset);

compareTo

Compares this offset to another offset in descending order. The offsets are compared in the order that they occur for the same time of day around the world. Thus, an offset of +10:00 comes before an offset of +09:00 and so on down to -18:00 . The comparison is «consistent with equals», as defined by Comparable .

equals

Checks if this offset is equal to another offset. The comparison is based on the amount of the offset in seconds. This is equivalent to a comparison by ID.

hashCode

toString

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Time zone offset java

Class ZoneOffset

public final class ZoneOffset extends ZoneId implements TemporalAccessor, TemporalAdjuster, ComparableZoneOffset>, Serializable

A time-zone offset from Greenwich/UTC, such as +02:00 . A time-zone offset is the amount of time that a time-zone differs from Greenwich/UTC. This is usually a fixed number of hours and minutes. Different parts of the world have different time-zone offsets. The rules for how offsets vary by place and time of year are captured in the ZoneId class. For example, Paris is one hour ahead of Greenwich/UTC in winter and two hours ahead in summer. The ZoneId instance for Paris will reference two ZoneOffset instances — a +01:00 instance for winter, and a +02:00 instance for summer. In 2008, time-zone offsets around the world extended from -12:00 to +14:00. To prevent any problems with that range being extended, yet still provide validation, the range of offsets is restricted to -18:00 to 18:00 inclusive. This class is designed for use with the ISO calendar system. The fields of hours, minutes and seconds make assumptions that are valid for the standard ISO definitions of those fields. This class may be used with other calendar systems providing the definition of the time fields matches those of the ISO calendar system. Instances of ZoneOffset must be compared using equals(java.lang.Object) . Implementations may choose to cache certain common offsets, however applications must not rely on such caching. This is a value-based class; use of identity-sensitive operations (including reference equality ( == ), identity hash code, or synchronization) on instances of ZoneOffset may have unpredictable results and should be avoided. The equals method should be used for comparisons.

Field Summary

Fields inherited from class java.time.ZoneId

Method Summary

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