Class MpscRelaxedArrayQueue<E>
- java.lang.Object
-
- java.util.AbstractCollection<E>
-
- java.util.AbstractQueue<E>
-
- org.jctools.queues.MpscRelaxedArrayQueue<E>
-
- All Implemented Interfaces:
Iterable<E>
,Collection<E>
,Queue<E>
,MessagePassingQueue<E>
public class MpscRelaxedArrayQueue<E> extends AbstractQueue<E> implements MessagePassingQueue<E>
This class is still work in progress, please do not pick up for production use just yet.
-
-
Nested Class Summary
-
Nested classes/interfaces inherited from interface org.jctools.queues.MessagePassingQueue
MessagePassingQueue.Consumer<T>, MessagePassingQueue.ExitCondition, MessagePassingQueue.Supplier<T>, MessagePassingQueue.WaitStrategy
-
-
Field Summary
Fields Modifier and Type Field Description protected long
consumerPosition
protected long
producerFirstCycleClaim
protected long
producerSecondCycleClaim
-
Fields inherited from interface org.jctools.queues.MessagePassingQueue
UNBOUNDED_CAPACITY
-
-
Constructor Summary
Constructors Constructor Description MpscRelaxedArrayQueue(int capacity)
-
Method Summary
All Methods Static Methods Instance Methods Concrete Methods Modifier and Type Method Description static int
activeCycleIndex(long activeCycleId)
int
capacity()
boolean
casActiveCycleId(long expected, long value)
protected boolean
casProducerCycleClaim(int cycleIndex, long expectedValue, long newValue)
void
clear()
Removes all items from the queue.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
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.protected long
getAndIncrementProducerCycleClaim(int cycleIndex)
boolean
isEmpty()
This method's accuracy is subject to concurrent modifications happening as the observation is carried out.Iterator<E>
iterator()
protected long
lpConsumerPosition()
long
lvActiveCycleId()
protected long
lvConsumerPosition()
protected long
lvProducerCycleClaim(int cycleIndex)
protected long
lvProducerLimit()
boolean
offer(E e)
Called from a producer thread subject to the restrictions appropriate to the implementation and according to theQueue.offer(Object)
interface.E
peek()
Called from the consumer thread subject to the restrictions appropriate to the implementation and according to theQueue.peek()
interface.E
poll()
Called from the consumer thread subject to the restrictions appropriate to the implementation and according to theQueue.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.void
soActiveCycleId(long value)
protected void
soConsumerPosition(long newValue)
protected void
soProducerCycleClaim(int cycleIndex, long value)
protected void
soProducerLimit(long newValue)
String
toString()
-
Methods inherited from class java.util.AbstractQueue
add, addAll, element, remove
-
Methods inherited from class java.util.AbstractCollection
contains, containsAll, remove, removeAll, retainAll, toArray, toArray
-
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, parallelStream, remove, removeAll, removeIf, retainAll, spliterator, stream, toArray, toArray, toArray
-
-
-
-
Method Detail
-
iterator
public Iterator<E> iterator()
- Specified by:
iterator
in interfaceCollection<E>
- Specified by:
iterator
in interfaceIterable<E>
- Specified by:
iterator
in classAbstractCollection<E>
-
offer
public boolean offer(E e)
Description copied from interface:MessagePassingQueue
Called from a producer thread subject to the restrictions appropriate to the implementation and according to theQueue.offer(Object)
interface.
-
poll
public E poll()
Description copied from interface:MessagePassingQueue
Called from the consumer thread subject to the restrictions appropriate to the implementation and according to theQueue.poll()
interface.
-
peek
public E peek()
Description copied from interface:MessagePassingQueue
Called from the consumer thread subject to the restrictions appropriate to the implementation and according to theQueue.peek()
interface.
-
size
public int size()
Description copied from interface:MessagePassingQueue
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. For some implementations this method may be O(n) rather than O(1).- Specified by:
size
in interfaceCollection<E>
- Specified by:
size
in interfaceMessagePassingQueue<E>
- Specified by:
size
in classAbstractCollection<E>
- Returns:
- number of messages in the queue, between 0 and
Integer.MAX_VALUE
but less or equals to capacity (if bounded).
-
clear
public void clear()
Description copied from interface:MessagePassingQueue
Removes all items from the queue. Called from the consumer thread subject to the restrictions appropriate to the implementation and according to theCollection.clear()
interface.- Specified by:
clear
in interfaceCollection<E>
- Specified by:
clear
in interfaceMessagePassingQueue<E>
- Overrides:
clear
in classAbstractQueue<E>
-
isEmpty
public boolean isEmpty()
Description copied from interface:MessagePassingQueue
This method's accuracy is subject to concurrent modifications happening as the observation is carried out.- Specified by:
isEmpty
in interfaceCollection<E>
- Specified by:
isEmpty
in interfaceMessagePassingQueue<E>
- Overrides:
isEmpty
in classAbstractCollection<E>
- Returns:
- true if empty, false otherwise
-
capacity
public int capacity()
- Specified by:
capacity
in interfaceMessagePassingQueue<E>
- Returns:
- the capacity of this queue or
MessagePassingQueue.UNBOUNDED_CAPACITY
if not bounded
-
relaxedOffer
public boolean relaxedOffer(E e)
Description copied from interface:MessagePassingQueue
Called from a producer thread subject to the restrictions appropriate to the implementation. As opposed toQueue.offer(Object)
this method may return false without the queue being full.- Specified by:
relaxedOffer
in interfaceMessagePassingQueue<E>
- Parameters:
e
- notnull
, will throw NPE if it is- Returns:
- true if element was inserted into the queue, false if unable to offer
-
relaxedPoll
public E relaxedPoll()
Description copied from interface:MessagePassingQueue
Called from the consumer thread subject to the restrictions appropriate to the implementation. As opposed toQueue.poll()
this method may returnnull
without the queue being empty.- Specified by:
relaxedPoll
in interfaceMessagePassingQueue<E>
- Returns:
- a message from the queue if one is available,
null
if unable to poll
-
relaxedPeek
public E relaxedPeek()
Description copied from interface:MessagePassingQueue
Called from the consumer thread subject to the restrictions appropriate to the implementation. As opposed toQueue.peek()
this method may returnnull
without the queue being empty.- Specified by:
relaxedPeek
in interfaceMessagePassingQueue<E>
- Returns:
- a message from the queue if one is available,
null
if unable to peek
-
drain
public int drain(MessagePassingQueue.Consumer<E> c)
Description copied from interface:MessagePassingQueue
Remove all available item from the queue and hand to consume. This should be semantically similar to: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.- Specified by:
drain
in interfaceMessagePassingQueue<E>
- Returns:
- the number of polled elements
-
fill
public int fill(MessagePassingQueue.Supplier<E> s)
Description copied from interface:MessagePassingQueue
Stuff the queue with elements from the supplier. Semantically similar to: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.- Specified by:
fill
in interfaceMessagePassingQueue<E>
- Returns:
- the number of offered elements
-
drain
public int drain(MessagePassingQueue.Consumer<E> c, int limit)
Description copied from interface:MessagePassingQueue
Remove up to limit elements from the queue and hand to consume. This should be semantically similar to: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.- Specified by:
drain
in interfaceMessagePassingQueue<E>
- Returns:
- the number of polled elements
-
fill
public int fill(MessagePassingQueue.Supplier<E> s, int limit)
Description copied from interface:MessagePassingQueue
Stuff the queue with up to limit elements from the supplier. Semantically similar to: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.- Specified by:
fill
in interfaceMessagePassingQueue<E>
- Returns:
- the number of offered elements
-
drain
public void drain(MessagePassingQueue.Consumer<E> c, MessagePassingQueue.WaitStrategy w, MessagePassingQueue.ExitCondition exit)
Description copied from interface:MessagePassingQueue
Remove elements from the queue and hand to consume forever. Semantically similar to: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.- Specified by:
drain
in interfaceMessagePassingQueue<E>
-
fill
public void fill(MessagePassingQueue.Supplier<E> s, MessagePassingQueue.WaitStrategy w, MessagePassingQueue.ExitCondition exit)
Description copied from interface:MessagePassingQueue
Stuff the queue with elements from the supplier forever. Semantically similar to: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 toMessagePassingQueue.Supplier.get()
make sure you have read and understood these before using this method.- Specified by:
fill
in interfaceMessagePassingQueue<E>
-
toString
public String toString()
- Overrides:
toString
in classAbstractCollection<E>
-
lvProducerCycleClaim
protected final long lvProducerCycleClaim(int cycleIndex)
-
soProducerCycleClaim
protected final void soProducerCycleClaim(int cycleIndex, long value)
-
getAndIncrementProducerCycleClaim
protected final long getAndIncrementProducerCycleClaim(int cycleIndex)
-
casProducerCycleClaim
protected final boolean casProducerCycleClaim(int cycleIndex, long expectedValue, long newValue)
-
lvConsumerPosition
protected final long lvConsumerPosition()
-
lpConsumerPosition
protected final long lpConsumerPosition()
-
soConsumerPosition
protected void soConsumerPosition(long newValue)
-
lvProducerLimit
protected final long lvProducerLimit()
-
soProducerLimit
protected final void soProducerLimit(long newValue)
-
activeCycleIndex
public static int activeCycleIndex(long activeCycleId)
-
lvActiveCycleId
public final long lvActiveCycleId()
-
casActiveCycleId
public final boolean casActiveCycleId(long expected, long value)
-
soActiveCycleId
public final void soActiveCycleId(long value)
-
-