Package org.jctools.queues

Interface QueueProgressIndicators

All Known Implementing Classes:
AtomicReferenceArrayQueue, ConcurrentSequencedCircularArrayQueue, ConcurrentSequencedCircularUnpaddedArrayQueue, FFBuffer, MpmcArrayQueue, MpmcAtomicArrayQueue, MpmcAtomicUnpaddedArrayQueue, MpmcUnboundedXaddArrayQueue, MpmcUnpaddedArrayQueue, MpscArrayQueue, MpscAtomicArrayQueue, MpscAtomicUnpaddedArrayQueue, MpscBlockingConsumerArrayQueue, MpscChunkedArrayQueue, MpscChunkedAtomicArrayQueue, MpscChunkedAtomicUnpaddedArrayQueue, MpscChunkedUnpaddedArrayQueue, MpscGrowableArrayQueue, MpscGrowableAtomicArrayQueue, MpscGrowableAtomicUnpaddedArrayQueue, MpscGrowableUnpaddedArrayQueue, MpscSequencedArrayQueue, MpscUnboundedArrayQueue, MpscUnboundedAtomicArrayQueue, MpscUnboundedAtomicUnpaddedArrayQueue, MpscUnboundedUnpaddedArrayQueue, MpscUnboundedXaddArrayQueue, MpscUnpaddedArrayQueue, SequencedAtomicReferenceArrayQueue, SpmcArrayQueue, SpmcAtomicArrayQueue, SpmcAtomicUnpaddedArrayQueue, SpmcUnpaddedArrayQueue, SpscArrayQueue, SpscAtomicArrayQueue, SpscAtomicUnpaddedArrayQueue, SpscChunkedArrayQueue, SpscChunkedAtomicArrayQueue, SpscChunkedAtomicUnpaddedArrayQueue, SpscChunkedUnpaddedArrayQueue, SpscGrowableArrayQueue, SpscGrowableAtomicArrayQueue, SpscGrowableAtomicUnpaddedArrayQueue, SpscGrowableUnpaddedArrayQueue, SpscUnboundedArrayQueue, SpscUnboundedAtomicArrayQueue, SpscUnboundedAtomicUnpaddedArrayQueue, SpscUnboundedUnpaddedArrayQueue, SpscUnpaddedArrayQueue
public interface QueueProgressIndicators
This interface is provided for monitoring purposes only and is only available on queues where it is easy to provide it. The producer/consumer progress indicators usually correspond with the number of elements offered/polled, but they are not guaranteed to maintain that semantic.

  • Method Summary

    Modifier and Type
    Method
    Description
    long
    currentConsumerIndex()
    This method has no concurrent visibility semantics.
    long
    currentProducerIndex()
    This method has no concurrent visibility semantics.

  • Method Details

    • currentProducerIndex

      long currentProducerIndex()
      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.
      Returns:
      the current value of the producer progress index

    • currentConsumerIndex

      long currentConsumerIndex()
      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.
      Returns:
      the current value of the consumer progress index