public class MpscArrayQueue<E> extends MpscArrayQueueL3Pad<E>
ConcurrentCircularArrayQueue
. This
implies that any thread may call the offer method, but only a single thread may call poll/peek for correctness to
maintained. MessagePassingQueue.Consumer<T>, MessagePassingQueue.ExitCondition, MessagePassingQueue.Supplier<T>, MessagePassingQueue.WaitStrategy
b000, b001, b002, b003, b004, b005, b006, b007, b010, b011, b012, b013, b014, b015, b016, b017, b020, b021, b022, b023, b024, b025, b026, b027, b030, b031, b032, b033, b034, b035, b036, b037, b040, b041, b042, b043, b044, b045, b046, b047, b050, b051, b052, b053, b054, b055, b056, b057, b060, b061, b062, b063, b064, b065, b066, b067, b070, b071, b072, b073, b074, b075, b076, b077, b100, b101, b102, b103, b104, b105, b106, b107, b110, b111, b112, b113, b114, b115, b116, b117, b120, b121, b122, b123, b124, b125, b126, b127, b130, b131, b132, b133, b134, b135, b136, b137, b140, b141, b142, b143, b144, b145, b146, b147, b150, b151, b152, b153, b154, b155, b156, b157, b160, b161, b162, b163, b164, b165, b166, b167, b170, b171, b172, b173, b174, b175, b176, b177
buffer, mask
UNBOUNDED_CAPACITY
Constructor and Description |
---|
MpscArrayQueue(int capacity) |
Modifier and Type | Method and Description |
---|---|
int |
drain(MessagePassingQueue.Consumer<E> c)
Remove all available item from the queue and hand to consume.
|
int |
drain(MessagePassingQueue.Consumer<E> c,
int limit)
Remove up to limit elements from the queue and hand to consume.
|
void |
drain(MessagePassingQueue.Consumer<E> c,
MessagePassingQueue.WaitStrategy w,
MessagePassingQueue.ExitCondition exit)
Remove elements from the queue and hand to consume forever.
|
int |
failFastOffer(E e)
A wait free alternative to offer which fails on CAS failure.
|
int |
fill(MessagePassingQueue.Supplier<E> s)
Stuff the queue with elements from the supplier.
|
int |
fill(MessagePassingQueue.Supplier<E> s,
int limit)
Stuff the queue with up to limit elements from the supplier.
|
void |
fill(MessagePassingQueue.Supplier<E> s,
MessagePassingQueue.WaitStrategy wait,
MessagePassingQueue.ExitCondition exit)
Stuff the queue with elements from the supplier forever.
|
boolean |
offer(E e)
Called from a producer thread subject to the restrictions appropriate to the implementation and
according to the
Queue.offer(Object) interface. |
boolean |
offerIfBelowThreshold(E e,
int threshold)
offer(E) } if ConcurrentCircularArrayQueue.size() is less than threshold. |
E |
peek()
Called from the consumer thread subject to the restrictions appropriate to the implementation and
according to the
Queue.peek() interface. |
E |
poll()
Called from the consumer thread subject to the restrictions appropriate to the implementation and
according to the
Queue.poll() interface. |
boolean |
relaxedOffer(E e)
Called from a producer thread subject to the restrictions appropriate to the implementation.
|
E |
relaxedPeek()
Called from the consumer thread subject to the restrictions appropriate to the implementation.
|
E |
relaxedPoll()
Called from the consumer thread subject to the restrictions appropriate to the implementation.
|
lpConsumerIndex, lvConsumerIndex, soConsumerIndex
lvProducerLimit, soProducerLimit
casProducerIndex, lvProducerIndex
capacity, clear, currentConsumerIndex, currentProducerIndex, isEmpty, iterator, size, toString
contains, containsAll, remove, removeAll, retainAll, toArray, toArray
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
public boolean offerIfBelowThreshold(E e, int threshold)
offer(E)
} if ConcurrentCircularArrayQueue.size()
is less than threshold.e
- the object to offer onto the queue, not nullthreshold
- the maximum allowable sizepublic boolean offer(E e)
Queue.offer(Object)
interface.
IMPLEMENTATION NOTES:
Lock free offer using a single CAS. As class name suggests access is permitted to many threads
concurrently.
e
- not null
, will throw NPE if it isQueue.offer(E)
,
MessagePassingQueue.offer(T)
public final int failFastOffer(E e)
e
- new element, not nullpublic E poll()
Queue.poll()
interface.
IMPLEMENTATION NOTES:
Lock free poll using ordered loads/stores. As class name suggests access is limited to a single thread.
null
iff emptyQueue.poll()
,
MessagePassingQueue.poll()
public E peek()
Queue.peek()
interface.
IMPLEMENTATION NOTES:
Lock free peek using ordered loads. As class name suggests access is limited to a single thread.
null
iff emptyQueue.poll()
,
MessagePassingQueue.poll()
public boolean relaxedOffer(E e)
MessagePassingQueue
Queue.offer(Object)
this method may return false without the queue being full.e
- not null
, will throw NPE if it ispublic E relaxedPoll()
MessagePassingQueue
Queue.poll()
this method may return null
without the queue being empty.null
if unable to pollpublic E relaxedPeek()
MessagePassingQueue
Queue.peek()
this method may return null
without the queue being empty.null
if unable to peekpublic int drain(MessagePassingQueue.Consumer<E> c, int limit)
MessagePassingQueue
M m;
int i = 0;
for(;i < limit && (m = relaxedPoll()) != null; i++){
c.accept(m);
}
return i;
There's no strong commitment to the queue being empty at the end of a drain. Called from a consumer thread subject to the restrictions appropriate to the implementation.
WARNING: Explicit assumptions are made with regards to MessagePassingQueue.Consumer.accept(T)
make sure you have read
and understood these before using this method.
public int fill(MessagePassingQueue.Supplier<E> s, int limit)
MessagePassingQueue
for(int i=0; i < limit && relaxedOffer(s.get()); i++);
There's no strong commitment to the queue being full at the end of a fill. Called from a producer
thread subject to the restrictions appropriate to the implementation.
WARNING: Explicit assumptions are made with regards to MessagePassingQueue.Supplier.get()
make sure you have read
and understood these before using this method.
public int drain(MessagePassingQueue.Consumer<E> c)
MessagePassingQueue
M m; while((m = relaxedPoll()) != null){ c.accept(m); }There's no strong commitment to the queue being empty at the end of a drain. Called from a consumer thread subject to the restrictions appropriate to the implementation.
WARNING: Explicit assumptions are made with regards to MessagePassingQueue.Consumer.accept(T)
make sure you have read
and understood these before using this method.
public int fill(MessagePassingQueue.Supplier<E> s)
MessagePassingQueue
while(relaxedOffer(s.get());There's no strong commitment to the queue being full at the end of a fill. Called from a producer thread subject to the restrictions appropriate to the implementation.
Unbounded queues will fill up the queue with a fixed amount rather than fill up to oblivion.
WARNING: Explicit assumptions are made with regards to MessagePassingQueue.Supplier.get()
make sure you have read
and understood these before using this method.
public void drain(MessagePassingQueue.Consumer<E> c, MessagePassingQueue.WaitStrategy w, MessagePassingQueue.ExitCondition exit)
MessagePassingQueue
int idleCounter = 0; while (exit.keepRunning()) { E e = relaxedPoll(); if(e==null){ idleCounter = wait.idle(idleCounter); continue; } idleCounter = 0; c.accept(e); }
Called from a consumer thread subject to the restrictions appropriate to the implementation.
WARNING: Explicit assumptions are made with regards to MessagePassingQueue.Consumer.accept(T)
make sure you have read
and understood these before using this method.
public void fill(MessagePassingQueue.Supplier<E> s, MessagePassingQueue.WaitStrategy wait, MessagePassingQueue.ExitCondition exit)
MessagePassingQueue
int idleCounter = 0;
while (exit.keepRunning()) {
E e = s.get();
while (!relaxedOffer(e)) {
idleCounter = wait.idle(idleCounter);
continue;
}
idleCounter = 0;
}
Called from a producer thread subject to the restrictions appropriate to the implementation. The main difference
being that implementors MUST assure room in the queue is available BEFORE calling MessagePassingQueue.Supplier.get()
.
WARNING: Explicit assumptions are made with regards to MessagePassingQueue.Supplier.get()
make sure you have read
and understood these before using this method.