Package com.oracle.coherence.concurrent.atomic

Class RemoteAtomicReference<V>

java.lang.Object

com.oracle.coherence.concurrent.atomic.RemoteAtomicReference<V>

Type Parameters:

V - the type of object referred to by this reference

All Implemented Interfaces:

AtomicReference<V>

public class RemoteAtomicReference<V>
extends Object
implements AtomicReference<V>

The remote implementation of AtomicReference, backed by a Coherence NamedMap entry.

Every method in this class is guaranteed to execute effectively-once, and provides cluster-wide atomicity guarantees for the backing atomic value. However, keep in mind that this comes at a significant cost -- each method invocation results in a network call to a remote owner of the backing atomic value, which means that each operation has significantly higher latency than a corresponding local implementation.

To somewhat reduce that performance penalty, consider using non-blocking AsyncAtomicReference implementation instead.

Since:

21.12

Author:

Aleks Seovic 2020.12.08

Nested Class Summary

Nested classes/interfaces inherited from interface com.oracle.coherence.concurrent.atomic.AtomicReference

AtomicReference.Serializer<V>

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	RemoteAtomicReference(NamedMap<String,AtomicReference<V>> mapAtomic, String sName)	Construct RemoteAtomicReference instance.

Method Summary

Modifier and Type	Method	Description
V	accumulateAndGet(V x, Remote.BinaryOperator<V> accumulatorFunction)	Atomically updates the current value with the results of applying the given function to the current and given values, returning the updated value.
V	accumulateAndGet(V x, BinaryOperator<V> accumulatorFunction)	Atomically updates the current value with the results of applying the given function to the current and given values, returning the updated value.
AsyncRemoteAtomicReference<V>	async()	Return non-blocking API for this atomic reference.
V	compareAndExchange(V expectedValue, V newValue)	Atomically sets the value to newValue if the current value, referred to as the witness value, is equal to the == expectedValue.
boolean	compareAndSet(V expectedValue, V newValue)	Atomically sets the value to newValue if the current value is equal to the expectedValue.
V	get()	Returns the current value.
V	getAndAccumulate(V x, Remote.BinaryOperator<V> accumulatorFunction)	Atomically updates the current value with the results of applying the given function to the current and given values, returning the previous value.
V	getAndAccumulate(V x, BinaryOperator<V> accumulatorFunction)	Atomically updates the current value with the results of applying the given function to the current and given values, returning the previous value.
V	getAndSet(V newValue)	Atomically sets the value to newValue and returns the old value.
V	getAndUpdate(Remote.UnaryOperator<V> updateFunction)	Atomically updates the current value with the results of applying the given function, returning the previous value.
V	getAndUpdate(UnaryOperator<V> updateFunction)	Atomically updates the current value with the results of applying the given function, returning the previous value.
protected <R> R	invoke(Remote.Function<AtomicReference<V>,R> function)	Apply specified function against the remote object and return the result.
protected <R> R	invoke(Remote.Function<AtomicReference<V>,R> function, boolean fMutate)	Apply specified function against the remote object and return the result.
void	set(V newValue)	Sets the value to newValue.
String	toString()	Returns the String representation of the current value.
V	updateAndGet(Remote.UnaryOperator<V> updateFunction)	Atomically updates the current value with the results of applying the given function, returning the updated value.
V	updateAndGet(UnaryOperator<V> updateFunction)	Atomically updates the current value with the results of applying the given function, returning the updated value.

Methods inherited from class java.lang.Object

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

Constructor Detail

RemoteAtomicReference

protected RemoteAtomicReference(NamedMap<String,AtomicReference<V>> mapAtomic,
                                String sName)

Construct RemoteAtomicReference instance.

Parameters:

mapAtomic - the map that holds this atomic value

sName - the name of this atomic value

Method Detail

async

public AsyncRemoteAtomicReference<V> async()

Description copied from interface: AtomicReference

Return non-blocking API for this atomic reference.

Specified by:

async in interface AtomicReference<V>

Returns:

non-blocking API for this atomic reference

get

public V get()

Description copied from interface: AtomicReference

Returns the current value.

Specified by:

get in interface AtomicReference<V>

Returns:

the current value

set

public void set(V newValue)

Description copied from interface: AtomicReference

Sets the value to newValue.

Specified by:

set in interface AtomicReference<V>

Parameters:

newValue - the new value

getAndSet

public V getAndSet(V newValue)

Description copied from interface: AtomicReference

Atomically sets the value to newValue and returns the old value.

Specified by:

getAndSet in interface AtomicReference<V>

Parameters:

newValue - the new value

Returns:

the previous value

compareAndSet

public boolean compareAndSet(V expectedValue,
                             V newValue)

Description copied from interface: AtomicReference

Atomically sets the value to newValue if the current value is equal to the expectedValue.

Specified by:

compareAndSet in interface AtomicReference<V>

Parameters:

expectedValue - the expected value

newValue - the new value

Returns:

true if successful. False return indicates that the actual value was not equal to the expected value.

getAndUpdate

public V getAndUpdate(Remote.UnaryOperator<V> updateFunction)

Description copied from interface: AtomicReference

Atomically updates the current value with the results of applying the given function, returning the previous value. The function should be side-effect-free, since it may be re-applied when attempted updates fail due to contention among threads.

Specified by:

getAndUpdate in interface AtomicReference<V>

Parameters:

updateFunction - a side-effect-free function

Returns:

the previous value

getAndUpdate

public V getAndUpdate(UnaryOperator<V> updateFunction)

Description copied from interface: AtomicReference

Atomically updates the current value with the results of applying the given function, returning the previous value. The function should be side-effect-free, since it may be re-applied when attempted updates fail due to contention among threads.

Specified by:

getAndUpdate in interface AtomicReference<V>

Parameters:

updateFunction - a side-effect-free function

Returns:

the previous value

updateAndGet

public V updateAndGet(Remote.UnaryOperator<V> updateFunction)

Description copied from interface: AtomicReference

Atomically updates the current value with the results of applying the given function, returning the updated value. The function should be side-effect-free, since it may be re-applied when attempted updates fail due to contention among threads.

Specified by:

updateAndGet in interface AtomicReference<V>

Parameters:

updateFunction - a side-effect-free function

Returns:

the updated value

updateAndGet

public V updateAndGet(UnaryOperator<V> updateFunction)

Description copied from interface: AtomicReference

Atomically updates the current value with the results of applying the given function, returning the updated value. The function should be side-effect-free, since it may be re-applied when attempted updates fail due to contention among threads.

Specified by:

updateAndGet in interface AtomicReference<V>

Parameters:

updateFunction - a side-effect-free function

Returns:

the updated value

getAndAccumulate

public V getAndAccumulate(V x,
                          Remote.BinaryOperator<V> accumulatorFunction)

Description copied from interface: AtomicReference

Atomically updates the current value with the results of applying the given function to the current and given values, returning the previous value.

The function should beside-effect-free, since it may be re-applied when attempted updates fail due to contention among threads. The function is applied with the current value as its first argument, and the given update as the second argument.

Specified by:

getAndAccumulate in interface AtomicReference<V>

Parameters:

x - the update value

accumulatorFunction - a side-effect-free function of two arguments

Returns:

the previous value

getAndAccumulate

public V getAndAccumulate(V x,
                          BinaryOperator<V> accumulatorFunction)

Description copied from interface: AtomicReference

Atomically updates the current value with the results of applying the given function to the current and given values, returning the previous value.

The function should beside-effect-free, since it may be re-applied when attempted updates fail due to contention among threads. The function is applied with the current value as its first argument, and the given update as the second argument.

Specified by:

getAndAccumulate in interface AtomicReference<V>

Parameters:

x - the update value

accumulatorFunction - a side-effect-free function of two arguments

Returns:

the previous value

accumulateAndGet

public V accumulateAndGet(V x,
                          Remote.BinaryOperator<V> accumulatorFunction)

Description copied from interface: AtomicReference

Atomically updates the current value with the results of applying the given function to the current and given values, returning the updated value.

The function should be side-effect-free, since it may be re-applied when attempted updates fail due to contention among threads. The function is applied with the current value as its first argument, and the given update as the second argument.

Specified by:

accumulateAndGet in interface AtomicReference<V>

Parameters:

x - the update value

accumulatorFunction - a side-effect-free function of two arguments

Returns:

the updated value

accumulateAndGet

public V accumulateAndGet(V x,
                          BinaryOperator<V> accumulatorFunction)

Description copied from interface: AtomicReference

Atomically updates the current value with the results of applying the given function to the current and given values, returning the updated value.

The function should be side-effect-free, since it may be re-applied when attempted updates fail due to contention among threads. The function is applied with the current value as its first argument, and the given update as the second argument.

Specified by:

accumulateAndGet in interface AtomicReference<V>

Parameters:

x - the update value

accumulatorFunction - a side-effect-free function of two arguments

Returns:

the updated value

compareAndExchange

public V compareAndExchange(V expectedValue,
                            V newValue)

Description copied from interface: AtomicReference

Atomically sets the value to newValue if the current value, referred to as the witness value, is equal to the == expectedValue.

Specified by:

compareAndExchange in interface AtomicReference<V>

Parameters:

expectedValue - the expected value

newValue - the new value

Returns:

the witness value, which will be the same as the expected value if successful

toString

public String toString()

Returns the String representation of the current value.

Overrides:

toString in class Object

Returns:

the String representation of the current value

invoke

protected <R> R invoke(Remote.Function<AtomicReference<V>,R> function)

Apply specified function against the remote object and return the result.

Any changes the function makes to the remote object will be preserved.

Type Parameters:

R - the type of the result

Parameters:

function - the function to apply

Returns:

the result of the function applied to a remote object

invoke

protected <R> R invoke(Remote.Function<AtomicReference<V>,R> function,
                       boolean fMutate)

Apply specified function against the remote object and return the result.

If the fMutate argument is true, any changes to the remote object will be preserved.

Type Parameters:

R - the type of the result

Parameters:

function - the function to apply

fMutate - flag specifying whether the function mutates the object

Returns:

the result of the function applied to a remote object