ZoneId Class

Definition

A time-zone ID, such as Europe/Paris.

[Android.Runtime.Register("java/time/ZoneId", ApiSince=26, DoNotGenerateAcw=true)]
public abstract class ZoneId : Java.Lang.Object, IDisposable, Java.Interop.IJavaPeerable, Java.IO.ISerializable
[<Android.Runtime.Register("java/time/ZoneId", ApiSince=26, DoNotGenerateAcw=true)>]
type ZoneId = class
    inherit Object
    interface ISerializable
    interface IJavaObject
    interface IDisposable
    interface IJavaPeerable
Inheritance
ZoneId
Derived
Attributes
Implements

Remarks

A time-zone ID, such as Europe/Paris.

A ZoneId is used to identify the rules used to convert between an Instant and a LocalDateTime. There are two distinct types of ID: <ul> <li>Fixed offsets - a fully resolved offset from UTC/Greenwich, that uses the same offset for all local date-times <li>Geographical regions - an area where a specific set of rules for finding the offset from UTC/Greenwich apply </ul> Most fixed offsets are represented by ZoneOffset. Calling #normalized() on any ZoneId will ensure that a fixed offset ID will be represented as a ZoneOffset.

The actual rules, describing when and how the offset changes, are defined by ZoneRules. This class is simply an ID used to obtain the underlying rules. This approach is taken because rules are defined by governments and change frequently, whereas the ID is stable.

The distinction has other effects. Serializing the ZoneId will only send the ID, whereas serializing the rules sends the entire data set. Similarly, a comparison of two IDs only examines the ID, whereas a comparison of two rules examines the entire data set.

<h2>Time-zone IDs</h2> The ID is unique within the system. There are three types of ID.

The simplest type of ID is that from ZoneOffset. This consists of 'Z' and IDs starting with '+' or '-'.

The next type of ID are offset-style IDs with some form of prefix, such as 'GMT+2' or 'UTC+01:00'. The recognised prefixes are 'UTC', 'GMT' and 'UT'. The offset is the suffix and will be normalized during creation. These IDs can be normalized to a ZoneOffset using normalized().

The third type of ID are region-based IDs. A region-based ID must be of two or more characters, and not start with 'UTC', 'GMT', 'UT' '+' or '-'. Region-based IDs are defined by configuration. The configuration focuses on providing the lookup from the ID to the underlying ZoneRules.

Time-zone rules are defined by governments and change frequently. There are a number of organizations, known here as groups, that monitor time-zone changes and collate them. The default group is the IANA Time Zone Database (TZDB). Other organizations include IATA (the airline industry body) and Microsoft.

Each group defines its own format for the region ID it provides. The TZDB group defines IDs such as 'Europe/London' or 'America/New_York'. TZDB IDs take precedence over other groups.

It is strongly recommended that the group name is included in all IDs supplied by groups other than TZDB to avoid conflicts. For example, IATA airline time-zone region IDs are typically the same as the three letter airport code. However, the airport of Utrecht has the code 'UTC', which is obviously a conflict. The recommended format for region IDs from groups other than TZDB is 'group~region'. Thus if IATA data were defined, Utrecht airport would be 'IATA~UTC'.

<h2>Serialization</h2> This class can be serialized and stores the string zone ID in the external form. The ZoneOffset subclass uses a dedicated format that only stores the offset from UTC/Greenwich.

A ZoneId can be deserialized in a Java Runtime where the ID is unknown. For example, if a server-side Java Runtime has been updated with a new zone ID, but the client-side Java Runtime has not been updated. In this case, the ZoneId object will exist, and can be queried using getId, equals, hashCode, toString, getDisplayName and normalized. However, any call to getRules will fail with ZoneRulesException. This approach is designed to allow a ZonedDateTime to be loaded and queried, but not modified, on a Java Runtime with incomplete time-zone information.

Added in 1.8.

Java documentation for java.time.ZoneId.

Portions of this page are modifications based on work created and shared by the Android Open Source Project and used according to terms described in the Creative Commons 2.5 Attribution License.

Constructors

ZoneId(IntPtr, JniHandleOwnership)

Properties

AvailableZoneIds
Class

Returns the runtime class of this Object.

(Inherited from Object)
Handle

The handle to the underlying Android instance.

(Inherited from Object)
Id
JniIdentityHashCode (Inherited from Object)
JniPeerMembers
PeerReference (Inherited from Object)
Rules
ShortIds
ThresholdClass
ThresholdType

Methods

Clone()

Creates and returns a copy of this object.

(Inherited from Object)
Dispose() (Inherited from Object)
Dispose(Boolean) (Inherited from Object)
Equals(Object)

Indicates whether some other object is "equal to" this one.

(Inherited from Object)
From(ITemporalAccessor)
GetDisplayName(TextStyle, Locale)
GetHashCode()

Returns a hash code value for the object.

(Inherited from Object)
JavaFinalize()

Called by the garbage collector on an object when garbage collection determines that there are no more references to the object.

(Inherited from Object)
Normalized()
Notify()

Wakes up a single thread that is waiting on this object's monitor.

(Inherited from Object)
NotifyAll()

Wakes up all threads that are waiting on this object's monitor.

(Inherited from Object)
Of(String)
Of(String, IDictionary<String,String>)
OfOffset(String, ZoneOffset)
SetHandle(IntPtr, JniHandleOwnership)

Sets the Handle property.

(Inherited from Object)
SystemDefault()
ToArray<T>() (Inherited from Object)
ToString()

Returns a string representation of the object.

(Inherited from Object)
UnregisterFromRuntime() (Inherited from Object)
Wait()

Causes the current thread to wait until it is awakened, typically by being <em>notified</em> or <em>interrupted</em>.

(Inherited from Object)
Wait(Int64)

Causes the current thread to wait until it is awakened, typically by being <em>notified</em> or <em>interrupted</em>, or until a certain amount of real time has elapsed.

(Inherited from Object)
Wait(Int64, Int32)

Causes the current thread to wait until it is awakened, typically by being <em>notified</em> or <em>interrupted</em>, or until a certain amount of real time has elapsed.

(Inherited from Object)

Explicit Interface Implementations

IJavaPeerable.Disposed() (Inherited from Object)
IJavaPeerable.DisposeUnlessReferenced() (Inherited from Object)
IJavaPeerable.Finalized() (Inherited from Object)
IJavaPeerable.JniManagedPeerState (Inherited from Object)
IJavaPeerable.SetJniIdentityHashCode(Int32) (Inherited from Object)
IJavaPeerable.SetJniManagedPeerState(JniManagedPeerStates) (Inherited from Object)
IJavaPeerable.SetPeerReference(JniObjectReference) (Inherited from Object)

Extension Methods

JavaCast<TResult>(IJavaObject)

Performs an Android runtime-checked type conversion.

JavaCast<TResult>(IJavaObject)
GetJniTypeName(IJavaPeerable)

Applies to