org.jctools.queues

Class SpscUnboundedArrayQueue<E>

java.lang.Object

java.util.AbstractCollection<E>

java.util.AbstractQueue<E>

org.jctools.queues.SpscUnboundedArrayQueue<E>

All Implemented Interfaces:

Iterable<E>, Collection<E>, Queue<E>, QueueProgressIndicators

public class SpscUnboundedArrayQueue<E>
extends AbstractQueue<E>

Field Summary

Fields

Modifier and Type	Field and Description
protected E[]	consumerBuffer
protected long	consumerIndex
protected long	consumerMask
protected static Object	JUMP
protected int	maxQueueCapacity
protected E[]	producerBuffer
protected long	producerIndex
protected long	producerLimit
protected int	producerLookAheadStep
protected long	producerMask

Constructor Summary

Constructors

Constructor and Description
SpscUnboundedArrayQueue(int chunkSize)

Method Summary

Modifier and Type	Method and Description
long	currentConsumerIndex() This method has no concurrent visibility semantics.
long	currentProducerIndex() This method has no concurrent visibility semantics.
Iterator<E>	iterator()
protected long	lvConsumerIndex()
protected E[]	lvNext(E[] curr)
protected long	lvProducerIndex()
boolean	offer(E e)
protected boolean	offerColdPath(E[] buffer, long mask, E e, long index, long offset)
E	peek()
E	poll()
int	size()
protected void	soConsumerIndex(long v)
protected void	soNext(E[] curr, E[] next)
protected void	soProducerIndex(long v)
protected void	writeToQueue(E[] buffer, E e, long index, long offset)

Methods inherited from class java.util.AbstractQueue

add, addAll, clear, element, remove

Methods inherited from class java.util.AbstractCollection

contains, containsAll, isEmpty, remove, removeAll, retainAll, toArray, toArray, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Collection

contains, containsAll, equals, hashCode, isEmpty, parallelStream, remove, removeAll, removeIf, retainAll, spliterator, stream, toArray, toArray

Methods inherited from interface java.lang.Iterable

forEach

Field Detail

JUMP

protected static final Object JUMP

consumerIndex

protected long consumerIndex

consumerMask

protected long consumerMask

consumerBuffer

protected E[] consumerBuffer

producerIndex

protected long producerIndex

maxQueueCapacity

protected int maxQueueCapacity

producerLookAheadStep

protected int producerLookAheadStep

producerLimit

protected long producerLimit

producerMask

protected long producerMask

producerBuffer

protected E[] producerBuffer

Constructor Detail

SpscUnboundedArrayQueue

public SpscUnboundedArrayQueue(int chunkSize)

Method Detail

offerColdPath

protected boolean offerColdPath(E[] buffer,
                                long mask,
                                E e,
                                long index,
                                long offset)

size

public int size()

Specified by:

size in interface Collection<E>

Specified by:

size in class AbstractCollection<E>

soProducerIndex

protected void soProducerIndex(long v)

soConsumerIndex

protected void soConsumerIndex(long v)

lvProducerIndex

protected long lvProducerIndex()

lvConsumerIndex

protected long lvConsumerIndex()

iterator

public final Iterator<E> iterator()

Specified by:

iterator in interface Iterable<E>

Specified by:

iterator in interface Collection<E>

Specified by:

iterator in class AbstractCollection<E>

currentProducerIndex

public long currentProducerIndex()

Description copied from interface: QueueProgressIndicators

This method has no concurrent visibility semantics. The value returned may be negative. Under normal circumstances 2 consecutive calls to this method can offer an idea of progress made by producer threads by subtracting the 2 results though in extreme cases (if producers have progressed by more than 2^64) this may also fail.
This value will normally indicate number of elements passed into the queue, but may under some circumstances be a derivative of that figure. This method should not be used to derive size or emptiness.

Specified by:

currentProducerIndex in interface QueueProgressIndicators

Returns:

the current value of the producer progress index

currentConsumerIndex

public long currentConsumerIndex()

Description copied from interface: QueueProgressIndicators

This method has no concurrent visibility semantics. The value returned may be negative. Under normal circumstances 2 consecutive calls to this method can offer an idea of progress made by consumer threads by subtracting the 2 results though in extreme cases (if consumers have progressed by more than 2^64) this may also fail.
This value will normally indicate number of elements taken out of the queue, but may under some circumstances be a derivative of that figure. This method should not be used to derive size or emptiness.

Specified by:

currentConsumerIndex in interface QueueProgressIndicators

Returns:

the current value of the consumer progress index

soNext

protected final void soNext(E[] curr,
                            E[] next)

lvNext

protected final E[] lvNext(E[] curr)

offer

public boolean offer(E e)

This implementation is correct for single producer thread use only.

Specified by:

offer in interface Queue<E>

writeToQueue

protected final void writeToQueue(E[] buffer,
                                  E e,
                                  long index,
                                  long offset)

poll

public E poll()

This implementation is correct for single consumer thread use only.

Specified by:

poll in interface Queue<E>

peek

public E peek()

This implementation is correct for single consumer thread use only.

Specified by:

peek in interface Queue<E>