io.atomix.core.semaphore

Interface AsyncAtomicSemaphore

All Superinterfaces:

AsyncPrimitive, DistributedPrimitive

public interface AsyncAtomicSemaphore
extends AsyncPrimitive

Distributed implementation of Semaphore.

Field Summary

Fields inherited from interface io.atomix.primitive.DistributedPrimitive

DEFAULT_OPERATION_TIMEOUT_MILLIS

Method Summary

Modifier and Type	Method and Description
CompletableFuture<Version>	acquire() Acquires a permit from this semaphore.
CompletableFuture<Version>	acquire(int permits) Acquires the given number of permits from this semaphore.
CompletableFuture<Integer>	availablePermits() Query the current number of permits available.
CompletableFuture<Integer>	drainPermits() Acquires and returns all permits that are immediately available.
CompletableFuture<Integer>	increasePermits(int permits) Increases the number of available permits by the indicated amount.
CompletableFuture<QueueStatus>	queueStatus() Query the waiting queue status.
CompletableFuture<Integer>	reducePermits(int permits) Shrinks the number of available permits by the indicated reduction.
CompletableFuture<Void>	release() Releases a permit.
CompletableFuture<Void>	release(int permits) Releases the given number of permits.
default AtomicSemaphore	sync() Returns a synchronous wrapper around the asynchronous primitive.
AtomicSemaphore	sync(Duration operationTimeout) Returns a synchronous wrapper around the asynchronous primitive.
CompletableFuture<Optional<Version>>	tryAcquire() Acquires a permit, if one is available and returns immediately.
CompletableFuture<Optional<Version>>	tryAcquire(Duration timeout) Acquires a permit from this semaphore if one becomes available within the given waiting time.
CompletableFuture<Optional<Version>>	tryAcquire(int permits) Acquires the given number of permits, if they are available and returns immediately.
CompletableFuture<Optional<Version>>	tryAcquire(int permits, Duration timeout) Acquires the given number of permits, if they are available within the given waiting time.

Methods inherited from interface io.atomix.primitive.AsyncPrimitive

close, delete

Methods inherited from interface io.atomix.primitive.DistributedPrimitive

addStateChangeListener, name, protocol, removeStateChangeListener, type

Method Detail

acquire

CompletableFuture<Version> acquire()

Acquires a permit from this semaphore.

Returns:

future to be completed once the permit has been acquired

acquire

CompletableFuture<Version> acquire(int permits)

Acquires the given number of permits from this semaphore.

Returns:

future to be completed once the permits has been acquired

tryAcquire

CompletableFuture<Optional<Version>> tryAcquire()

Acquires a permit, if one is available and returns immediately.

Returns:

future to be completed with a boolean indicating whether the permit was acquired

tryAcquire

CompletableFuture<Optional<Version>> tryAcquire(int permits)

Acquires the given number of permits, if they are available and returns immediately.

Parameters:

permits - permits to acquire

Returns:

future to be completed with a boolean indicating whether the permits was acquired

tryAcquire

CompletableFuture<Optional<Version>> tryAcquire(Duration timeout)

Acquires a permit from this semaphore if one becomes available within the given waiting time.

Parameters:

timeout - the maximum time to wait for a permit

Returns:

future to be completed with a boolean indicating whether the permit was acquired

tryAcquire

CompletableFuture<Optional<Version>> tryAcquire(int permits,
                                                Duration timeout)

Acquires the given number of permits, if they are available within the given waiting time.

Parameters:

permits - permits to acquire

timeout - the maximum time to wait for a permit

Returns:

future to be completed with a boolean indicating whether the permits was acquired

release

CompletableFuture<Void> release()

Releases a permit.

Returns:

future to be completed once the permit has been released

release

CompletableFuture<Void> release(int permits)

Releases the given number of permits.

Parameters:

permits - permits to release

Returns:

future to be completed once the permits has been released

availablePermits

CompletableFuture<Integer> availablePermits()

Query the current number of permits available.

Returns:

a future for available permits

drainPermits

CompletableFuture<Integer> drainPermits()

Acquires and returns all permits that are immediately available. If the initial permits is negative, this will set available permits to 0, and return a negative number. If a positive number is returned, the acquired permits will be recorded. If the Client disconnects, these permits will be automatically released.

Returns:

the future complete with number of permits acquired

increasePermits

CompletableFuture<Integer> increasePermits(int permits)

Increases the number of available permits by the indicated amount. This method differs from release in that it does not effect the amount of permits this caller has acquired.

Parameters:

permits - the number of permits to add

Returns:

the future complete with available permits after increase

reducePermits

CompletableFuture<Integer> reducePermits(int permits)

Shrinks the number of available permits by the indicated reduction. This method differs from acquire in that it does not block waiting for permits to become available and can be reduced to negative.

Parameters:

permits - the number of permits to remove

Returns:

the future complete with available permits after increase

queueStatus

CompletableFuture<QueueStatus> queueStatus()

Query the waiting queue status.

Returns:

the future complete with waiting queue status

sync

default AtomicSemaphore sync()

Description copied from interface: AsyncPrimitive

Returns a synchronous wrapper around the asynchronous primitive.

Specified by:

sync in interface AsyncPrimitive

Returns:

the synchronous primitive

sync

AtomicSemaphore sync(Duration operationTimeout)

Description copied from interface: AsyncPrimitive

Returns a synchronous wrapper around the asynchronous primitive.

Specified by:

sync in interface AsyncPrimitive

Parameters:

operationTimeout - the synchronous operation timeout

Returns:

the synchronous primitive