Interface QueueProgressIndicators

All Known Implementing Classes:
AtomicReferenceArrayQueue, BaseMpscLinkedArrayQueue, BaseMpscLinkedAtomicArrayQueue, BaseSpscLinkedArrayQueue, BaseSpscLinkedAtomicArrayQueue, ConcurrentCircularArrayQueue, ConcurrentSequencedCircularArrayQueue, FFBuffer, FFBufferConsumerField, FFBufferL1Pad, FFBufferL2Pad, FFBufferL3Pad, FFBufferProducerField, MpmcArrayQueue, MpmcArrayQueueConsumerIndexField, MpmcArrayQueueL1Pad, MpmcArrayQueueL2Pad, MpmcArrayQueueL3Pad, MpmcArrayQueueProducerIndexField, MpmcAtomicArrayQueue, MpmcAtomicArrayQueueConsumerIndexField, MpmcAtomicArrayQueueL1Pad, MpmcAtomicArrayQueueL2Pad, MpmcAtomicArrayQueueL3Pad, MpmcAtomicArrayQueueProducerIndexField, MpmcUnboundedXaddArrayQueue, MpscArrayQueue, MpscArrayQueueConsumerIndexField, MpscArrayQueueL1Pad, MpscArrayQueueL2Pad, MpscArrayQueueL3Pad, MpscArrayQueueMidPad, MpscArrayQueueProducerIndexField, MpscArrayQueueProducerLimitField, MpscAtomicArrayQueue, MpscAtomicArrayQueueConsumerIndexField, MpscAtomicArrayQueueL1Pad, MpscAtomicArrayQueueL2Pad, MpscAtomicArrayQueueL3Pad, MpscAtomicArrayQueueMidPad, MpscAtomicArrayQueueProducerIndexField, MpscAtomicArrayQueueProducerLimitField, MpscBlockingConsumerArrayQueue, MpscChunkedArrayQueue, MpscChunkedArrayQueueColdProducerFields, MpscChunkedAtomicArrayQueue, MpscChunkedAtomicArrayQueueColdProducerFields, MpscGrowableArrayQueue, MpscGrowableAtomicArrayQueue, MpscSequencedArrayQueue, MpscSequencedArrayQueueConsumerField, MpscSequencedArrayQueueL1Pad, MpscSequencedArrayQueueL2Pad, MpscSequencedArrayQueueProducerField, MpscUnboundedArrayQueue, MpscUnboundedAtomicArrayQueue, MpscUnboundedXaddArrayQueue, MpUnboundedXaddArrayQueue, SequencedAtomicReferenceArrayQueue, SpmcArrayQueue, SpmcArrayQueueConsumerIndexField, SpmcArrayQueueL1Pad, SpmcArrayQueueL2Pad, SpmcArrayQueueL3Pad, SpmcArrayQueueMidPad, SpmcArrayQueueProducerIndexCacheField, SpmcArrayQueueProducerIndexField, SpmcAtomicArrayQueue, SpmcAtomicArrayQueueConsumerIndexField, SpmcAtomicArrayQueueL1Pad, SpmcAtomicArrayQueueL2Pad, SpmcAtomicArrayQueueL3Pad, SpmcAtomicArrayQueueMidPad, SpmcAtomicArrayQueueProducerIndexCacheField, SpmcAtomicArrayQueueProducerIndexField, SpscArrayQueue, SpscArrayQueueColdField, SpscArrayQueueConsumerIndexField, SpscArrayQueueL1Pad, SpscArrayQueueL2Pad, SpscArrayQueueL3Pad, SpscArrayQueueProducerIndexFields, SpscAtomicArrayQueue, SpscAtomicArrayQueueColdField, SpscAtomicArrayQueueConsumerIndexField, SpscAtomicArrayQueueL1Pad, SpscAtomicArrayQueueL2Pad, SpscAtomicArrayQueueL3Pad, SpscAtomicArrayQueueProducerIndexFields, SpscChunkedArrayQueue, SpscChunkedAtomicArrayQueue, SpscGrowableArrayQueue, SpscGrowableAtomicArrayQueue, SpscUnboundedArrayQueue, SpscUnboundedAtomicArrayQueue

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
    This method has no concurrent visibility semantics.
    long
    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