abstract class BaseLinkedUnpaddedQueue<E> extends BaseLinkedUnpaddedQueuePad2<E>
MessagePassingQueue.Consumer<T>, MessagePassingQueue.ExitCondition, MessagePassingQueue.Supplier<T>, MessagePassingQueue.WaitStrategyP_NODE_OFFSETUNBOUNDED_CAPACITY| Constructor and Description |
|---|
BaseLinkedUnpaddedQueue() |
| Modifier and Type | Method and Description |
|---|---|
int |
capacity() |
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 wait,
MessagePassingQueue.ExitCondition exit)
Remove elements from the queue and hand to consume forever.
|
protected E |
getSingleConsumerNodeValue(LinkedQueueNode<E> currConsumerNode,
LinkedQueueNode<E> nextNode) |
boolean |
isEmpty()
This method's accuracy is subject to concurrent modifications happening as the observation is carried
out.
|
java.util.Iterator<E> |
iterator() |
protected LinkedQueueNode<E> |
newNode() |
protected LinkedQueueNode<E> |
newNode(E e) |
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.
|
(package private) LinkedQueueNode<E> |
spinWaitForNextNode(LinkedQueueNode<E> currNode) |
java.lang.String |
toString() |
lpConsumerNode, lvConsumerNode, spConsumerNodecasProducerNode, lpProducerNode, lvProducerNode, soProducerNode, spProducerNodecontains, containsAll, remove, removeAll, retainAll, toArray, toArrayclone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, waitclear, fill, fill, fill, offerpublic final java.util.Iterator<E> iterator()
public java.lang.String toString()
toString in class java.util.AbstractCollection<E>protected final LinkedQueueNode<E> newNode()
protected final LinkedQueueNode<E> newNode(E e)
public final int size()
IMPLEMENTATION NOTES:
This is an O(n) operation as we run through all the nodes and count them.
The accuracy of the value returned by this method is subject to races with producer/consumer threads. In
particular when racing with the consumer thread this method may under estimate the size.
size in interface java.util.Collection<E>size in interface MessagePassingQueue<E>size in class java.util.AbstractCollection<E>Integer.MAX_VALUE but less or equals to
capacity (if bounded).Collection.size()public boolean isEmpty()
IMPLEMENTATION NOTES:
Queue is empty when producerNode is the same as consumerNode. An alternative implementation would be to
observe the producerNode.value is null, which also means an empty queue because only the
consumerNode.value is allowed to be null.
isEmpty in interface java.util.Collection<E>isEmpty in interface MessagePassingQueue<E>isEmpty in class java.util.AbstractCollection<E>MessagePassingQueue.isEmpty()protected E getSingleConsumerNodeValue(LinkedQueueNode<E> currConsumerNode, LinkedQueueNode<E> nextNode)
public E poll()
Queue.poll() interface.
IMPLEMENTATION NOTES:
Poll is allowed from a SINGLE thread.
Poll is potentially blocking here as the Queue.poll() does not allow returning null if the queue is not
empty. This is very different from the original Vyukov guarantees. See relaxedPoll() for the original
semantics.
Poll reads consumerNode.next and:
null AND the queue is empty return null, if queue is not empty spin wait for
value to become visible.
null set it as the consumer node and return it's now evacuated value.
null, which is also the starting point for the queue.
Because null values are not allowed to be offered this is the only node with it's value set to
null at any one time.null iff emptyMessagePassingQueue.poll(),
Queue.poll()public E peek()
Queue.peek() interface.
IMPLEMENTATION NOTES:
Peek is allowed from a SINGLE thread.
Peek is potentially blocking here as the Queue.peek() does not allow returning null if the queue is not
empty. This is very different from the original Vyukov guarantees. See relaxedPeek() for the original
semantics.
Poll reads the next node from the consumerNode and:
null AND the queue is empty return null, if queue is not empty spin wait for
value to become visible.
null return it's value.
null iff emptyMessagePassingQueue.peek(),
Queue.peek()LinkedQueueNode<E> spinWaitForNextNode(LinkedQueueNode<E> currNode)
public E relaxedPoll()
MessagePassingQueueQueue.poll() this method may return null without the queue being empty.null if unable to pollpublic E relaxedPeek()
MessagePassingQueueQueue.peek() this method may return null without the queue being empty.null if unable to peekpublic 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 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 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 void drain(MessagePassingQueue.Consumer<E> c, MessagePassingQueue.WaitStrategy wait, 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 int capacity()
MessagePassingQueue.UNBOUNDED_CAPACITY if not bounded