Package io.airlift.concurrent

Class DynamicSizeBoundQueue<T>

java.lang.Object

io.airlift.concurrent.DynamicSizeBoundQueue<T>

@ThreadSafe
public class DynamicSizeBoundQueue<T>
extends Object

Size constrained queue that utilizes a dynamic element size function. To prevent starvation for adding large elements, the queue will only block new elements if the total size has already been reached or exceeded. This means in the normal case, the queue should be no larger than the max size plus the size of one element. Callers also have the additional option to force insert further elements without regard for size constraints. In the current implementation, elements are required to have positive sizes (they cannot have zero size). This implementation is designed to closely mirror the method signatures of BlockingQueue.

Constructor Summary

Constructors

Constructor	Description
DynamicSizeBoundQueue(long maxSize, ToLongFunction<T> elementSizeFunction)
DynamicSizeBoundQueue(long maxSize, ToLongFunction<T> elementSizeFunction, com.google.common.base.Ticker ticker)

Method Summary

Modifier and Type	Method	Description
void	forcePut(T element)	Insert without regard to the max size (potentially exceeding the max limit).
long	getMaxSize()
long	getSize()	Gets the current size of the queue.
boolean	offer(T element)
boolean	offer(T element, long timeout, TimeUnit unit)
Optional<com.google.common.util.concurrent.ListenableFuture<Void>>	offerWithBackoff(T element)	Enqueue the element if there is space, otherwise returns a ListenableFuture that will complete when space becomes available for the element.
T	poll()
T	poll(long timeout, TimeUnit unit)
void	put(T element)
T	take()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

DynamicSizeBoundQueue

public DynamicSizeBoundQueue(long maxSize,
 ToLongFunction<T> elementSizeFunction)

DynamicSizeBoundQueue

public DynamicSizeBoundQueue(long maxSize,
 ToLongFunction<T> elementSizeFunction,
 com.google.common.base.Ticker ticker)

Method Details

getMaxSize

public long getMaxSize()

getSize

public long getSize()

Gets the current size of the queue. The size is guaranteed to be no larger than max size plus the size of one element if forcePut(Object) is not used.

offer

public boolean offer(T element)

offer

public boolean offer(T element,
 long timeout,
 TimeUnit unit)
              throws InterruptedException

Throws:

InterruptedException

put

public void put(T element)
         throws InterruptedException

Throws:

InterruptedException

offerWithBackoff

public Optional<com.google.common.util.concurrent.ListenableFuture<Void>> offerWithBackoff(T element)

Enqueue the element if there is space, otherwise returns a ListenableFuture that will complete when space becomes available for the element. If a future is returned, the element was not inserted.

forcePut

public void forcePut(T element)

Insert without regard to the max size (potentially exceeding the max limit). This can throw an IllegalStateException if the forced element triggers a numeric overflow, in which case the element is not inserted.

poll

@Nullable
public T poll()

poll

public T poll(long timeout,
 TimeUnit unit)
       throws InterruptedException

Throws:

InterruptedException

take

public T take()
       throws InterruptedException

Throws:

InterruptedException