Clock Class

Definition

[Android.Runtime.Register("java/time/Clock", ApiSince=26, DoNotGenerateAcw=true)]
public abstract class Clock : Java.Lang.Object, IDisposable, Java.Interop.IJavaPeerable, Java.Time.IInstantSource

[<Android.Runtime.Register("java/time/Clock", ApiSince=26, DoNotGenerateAcw=true)>]
type Clock = class
    inherit Object
    interface IInstantSource
    interface IJavaObject
    interface IDisposable
    interface IJavaPeerable

Inheritance

Object

Object

Clock

Attributes

RegisterAttribute

Implements

IJavaObject IJavaPeerable IInstantSource IDisposable

Remarks

A clock providing access to the current instant, date and time using a time-zone.

Instances of this abstract class are used to access a pluggable representation of the current instant, which can be interpreted using the stored time-zone to find the current date and time. For example, Clock can be used instead of System#currentTimeMillis() and TimeZone#getDefault().

Use of a Clock is optional. All key date-time classes also have a now() factory method that uses the system clock in the default time zone. The primary purpose of this abstraction is to allow alternate clocks to be plugged in as and when required. Applications use an object to obtain the current time rather than a static method. This can simplify testing.

As such, this abstract class does not guarantee the result actually represents the current instant on the time-line. Instead, it allows the application to provide a controlled view as to what the current instant and time-zone are.

Best practice for applications is to pass a Clock into any method that requires the current instant and time-zone. A dependency injection framework is one way to achieve this:

public class MyBean {
               private Clock clock;  // dependency inject
               ...
               public void process(LocalDate eventDate) {
                 if (eventDate.isBefore(LocalDate.now(clock)) {
                   ...
                 }
               }
             }

This approach allows an alternative clock, such as #fixed(Instant, ZoneId) fixed or #offset(Clock, Duration) offset to be used during testing.

The system factory methods provide clocks based on the best available system clock. This may use System#currentTimeMillis(), or a higher resolution clock if one is available.

Added in 1.8.

Java documentation for java.time.Clock.

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

Properties

Methods

Explicit Interface Implementations

Extension Methods

Applies to