E - public class MpscAtomicArrayQueue<E> extends AbstractQueue<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| Modifier and Type | Field and Description |
|---|---|
protected AtomicReferenceArray<E> |
buffer |
protected long |
consumerIndex |
protected int |
mask |
UNBOUNDED_CAPACITY| Constructor and Description |
|---|
MpscAtomicArrayQueue(int capacity) |
| Modifier and Type | Method and Description |
|---|---|
protected int |
calcElementOffset(long index) |
protected int |
calcElementOffset(long index,
int mask) |
int |
capacity() |
protected boolean |
casProducerIndex(long expect,
long newValue) |
void |
clear()
Removes all items from the queue.
|
long |
currentConsumerIndex()
This method has no concurrent visibility semantics.
|
long |
currentProducerIndex()
This method has no concurrent visibility semantics.
|
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 w,
MessagePassingQueue.ExitCondition exit)
Stuff the queue with elements from the supplier forever.
|
boolean |
isEmpty()
This method's accuracy is subject to concurrent modifications happening as the observation is carried
out.
|
Iterator<E> |
iterator() |
protected long |
lpConsumerIndex() |
static <E> E |
lpElement(AtomicReferenceArray<E> buffer,
int offset) |
protected E |
lpElement(int offset) |
long |
lvConsumerIndex() |
static <E> E |
lvElement(AtomicReferenceArray<E> buffer,
int offset) |
protected E |
lvElement(int offset) |
long |
lvProducerIndex() |
protected long |
lvProducerLimit() |
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)
|
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.
|
int |
size()
This method's accuracy is subject to concurrent modifications happening as the size is estimated and as
such is a best effort rather than absolute value.
|
protected void |
soConsumerIndex(long newValue) |
static <E> void |
soElement(AtomicReferenceArray<E> buffer,
int offset,
E value) |
protected void |
soElement(int offset,
E value) |
protected void |
soProducerLimit(long newValue) |
static <E> void |
spElement(AtomicReferenceArray<E> buffer,
int offset,
E value) |
protected void |
spElement(int offset,
E value) |
static <E> void |
svElement(AtomicReferenceArray<E> buffer,
int offset,
E value) |
String |
toString() |
int |
weakOffer(E e)
Deprecated.
This was renamed to failFastOffer please migrate
|
add, addAll, element, removecontains, containsAll, remove, removeAll, retainAll, toArray, toArrayclone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, waitcontains, containsAll, equals, hashCode, parallelStream, remove, removeAll, removeIf, retainAll, spliterator, stream, toArray, toArrayprotected volatile long consumerIndex
protected final AtomicReferenceArray<E> buffer
protected final int mask
public boolean offerIfBelowThreshold(E e, int 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.
Queue.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.
Queue.poll(),
MessagePassingQueue.poll()public boolean relaxedOffer(E e)
MessagePassingQueueQueue.offer(Object) this method may return false without the queue being full.e - not null, will throw NPE if it ispublic E relaxedPoll()
MessagePassingQueueQueue.poll() this method may return null without the queue being empty.public E relaxedPeek()
MessagePassingQueueQueue.peek() this method may return null without the queue being empty.public int drain(MessagePassingQueue.Consumer<E> c)
MessagePassingQueue
M m;
while((m = relaxedPoll()) != null){
c.accept(m);
}
public int fill(MessagePassingQueue.Supplier<E> s)
MessagePassingQueue
while(relaxedOffer(s.get());
public 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.
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.
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.
public void fill(MessagePassingQueue.Supplier<E> s, MessagePassingQueue.WaitStrategy w, 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.
@Deprecated public int weakOffer(E e)
protected final long lpConsumerIndex()
public final long lvConsumerIndex()
protected void soConsumerIndex(long newValue)
protected final long lvProducerLimit()
protected final void soProducerLimit(long newValue)
public final long lvProducerIndex()
protected final boolean casProducerIndex(long expect,
long newValue)
public Iterator<E> iterator()
iterator in interface Iterable<E>iterator in interface Collection<E>iterator in class AbstractCollection<E>public String toString()
toString in class AbstractCollection<E>public void clear()
MessagePassingQueueCollection.clear() interface.clear in interface Collection<E>clear in interface MessagePassingQueue<E>clear in class AbstractQueue<E>protected final int calcElementOffset(long index,
int mask)
protected final int calcElementOffset(long index)
public static <E> E lvElement(AtomicReferenceArray<E> buffer, int offset)
public static <E> E lpElement(AtomicReferenceArray<E> buffer, int offset)
protected final E lpElement(int offset)
public static <E> void spElement(AtomicReferenceArray<E> buffer, int offset, E value)
protected final void spElement(int offset,
E value)
public static <E> void soElement(AtomicReferenceArray<E> buffer, int offset, E value)
protected final void soElement(int offset,
E value)
public static <E> void svElement(AtomicReferenceArray<E> buffer, int offset, E value)
protected final E lvElement(int offset)
public final int capacity()
capacity in interface MessagePassingQueue<E>MessagePassingQueue.UNBOUNDED_CAPACITY if not boundedpublic final int size()
size in interface Collection<E>size in interface MessagePassingQueue<E>size in class AbstractCollection<E>Integer.MAX_VALUE but less or equals to
capacity (if bounded).public final boolean isEmpty()
MessagePassingQueueisEmpty in interface Collection<E>isEmpty in interface MessagePassingQueue<E>isEmpty in class AbstractCollection<E>public final long currentProducerIndex()
QueueProgressIndicatorscurrentProducerIndex in interface QueueProgressIndicatorspublic final long currentConsumerIndex()
QueueProgressIndicatorscurrentConsumerIndex in interface QueueProgressIndicatorsCopyright © 2013–2018. All rights reserved.