org.openbase.jul.pattern

Class ObservableImpl<T>

java.lang.Object

org.openbase.jul.pattern.AbstractObservable<T>

org.openbase.jul.pattern.ObservableImpl<T>

Type Parameters:

T - the data type on whose changes is notified

All Implemented Interfaces:

Shutdownable, Observable<T>

public class ObservableImpl<T>
extends AbstractObservable<T>

Author:

Divine Threepwood

Nested Class Summary

Nested classes/interfaces inherited from interface org.openbase.jul.iface.Shutdownable

Shutdownable.ShutdownDeamon

Field Summary

Fields

Modifier and Type	Field and Description
protected Object	VALUE_LOCK

Fields inherited from class org.openbase.jul.pattern.AbstractObservable

latestValueHash, observers, unchangedValueFilter

Constructor Summary

Constructors

Constructor and Description
ObservableImpl()
ObservableImpl(boolean unchangedValueFilter)
ObservableImpl(boolean unchangedValueFilter, Object source)
ObservableImpl(Object source)

Method Summary

Modifier and Type	Method and Description
protected void	applyValueUpdate(T value) Method is called if a observer notification delivers a new value.
T	getValue() Method returns the latest observable value.
CompletableFuture<T>	getValueFuture() Method returns a Future object which represents the value availability.
boolean	isValueAvailable() Checks if a value was ever notified.
void	waitForValue(long timeout, TimeUnit timeUnit) Method blocks until the observable is available.

Methods inherited from class org.openbase.jul.pattern.AbstractObservable

addObserver, isNotificationInProgess, notifyObservers, notifyObservers, removeObserver, setExecutorService, setHashGenerator, shutdown, toString, waitUntilNotificationIsFinished

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.openbase.jul.pattern.Observable

getLatestValue, waitForValue

Methods inherited from interface org.openbase.jul.iface.Shutdownable

registerShutdownHook, registerShutdownHook

Field Detail

VALUE_LOCK

protected final Object VALUE_LOCK

Constructor Detail

ObservableImpl

public ObservableImpl()

ObservableImpl

public ObservableImpl(Object source)

Parameters:

source -

ObservableImpl

public ObservableImpl(boolean unchangedValueFilter)

Parameters:

unchangedValueFilter -

ObservableImpl

public ObservableImpl(boolean unchangedValueFilter,
                      Object source)

Parameters:

unchangedValueFilter -

source -

Method Detail

waitForValue

public void waitForValue(long timeout,
                         TimeUnit timeUnit)
                  throws CouldNotPerformException,
                         InterruptedException

Method blocks until the observable is available. In case the given timeout is reached an TimeoutException is thrown.

Parameters:

timeout - is the timeout related to the given TimeUnit.

timeUnit - is the unit of the timeout.

Throws:

InterruptedException - is thrown if the current thread was interrupted externally.

CouldNotPerformException - is thrown with a TimeoutException cause if the given timeout is reached.

getValue

public T getValue()
           throws NotAvailableException

Method returns the latest observable value.

Returns:

the latest value of the observable.

Throws:

NotAvailableException

getValueFuture

public CompletableFuture<T> getValueFuture()

Method returns a Future object which represents the value availability.

Returns:

a future object providing the value.

isValueAvailable

public boolean isValueAvailable()

Checks if a value was ever notified.

Returns:

true if the value is available.

applyValueUpdate

protected void applyValueUpdate(T value)
                         throws NotAvailableException

Method is called if a observer notification delivers a new value.

Overrides:

applyValueUpdate in class AbstractObservable<T>

Parameters:

value - the new value

Note: Overwrite this method for getting informed about value changes.

Throws:

NotAvailableException