arez

Class ComputedValue<T>

java.lang.Object

arez.Node

arez.ComputedValue<T>

All Implemented Interfaces:

Disposable

public final class ComputedValue<T>
extends Node

The ComputedValue represents an Observable derived from other observables within the Arez system. The value is calculated lazily. i.e. The ComputedValue will only be calculated if there is current observers on the calculated value.

It should be notes that the ComputedValue is backed by both an Observable and an Observer. The id's of each of these nodes differ but they share the name and thus while debugging appear to be a single element.

Method Summary

Modifier and Type	Method and Description
void	dispose() Dispose the ComputedValue so that it can no longer be used.
T	get() Return the computed value, calculating the value if it is not up to date.
boolean	isDisposed() Return true if dispose() has been called on object.

Methods inherited from class arez.Node

getName, toString

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface arez.Disposable

asDisposable, dispose, isDisposed

Method Detail

get

public T get()

Return the computed value, calculating the value if it is not up to date.

Returns:

the computed value.

dispose

public void dispose()

Dispose the ComputedValue so that it can no longer be used.

isDisposed

public boolean isDisposed()

Return true if dispose() has been called on object. This is very useful when the Disposable is a @Computed value representing the selected item in a UI component but the item can be disposed by other agents within the system. (i.e. The item was removed from the server).

Returns:

true if dispose has been called.