Package org.jgroups.util

Class ConcurrentLinkedBlockingQueue<T>

java.lang.Object

java.util.AbstractCollection<T>

java.util.AbstractQueue<T>

java.util.concurrent.ConcurrentLinkedQueue<T>

org.jgroups.util.ConcurrentLinkedBlockingQueue<T>

All Implemented Interfaces:

Serializable, Iterable<T>, Collection<T>, BlockingQueue<T>, Queue<T>

public class ConcurrentLinkedBlockingQueue<T>
extends ConcurrentLinkedQueue<T>
implements BlockingQueue<T>

Attempt at writing a fast transfer queue, which is bounded. The take() method blocks until there is an element, but the offer() method drops the element and returns if the queue is full (doesn't block). I thought this class would be useful in ThreadPoolExecutor, as a replacement for LinkedBlockingQueue, but the perf didn't change. I'll keep it for later reference ...

See Also:

• Serialized Form

Field Summary

Fields

Modifier and Type	Field	Description
private final int	capacity
private final Lock	lock
private final Condition	not_empty
private static final long	serialVersionUID
private final AtomicInteger	waiting_takers

Constructor Summary

Constructors

Constructor	Description
ConcurrentLinkedBlockingQueue(int capacity)

Method Summary

Modifier and Type	Method	Description
int	drainTo(Collection<? super T> c)
int	drainTo(Collection<? super T> c, int maxElements)
boolean	offer(T t)	Drops elements if capacity has been reached.
boolean	offer(T t, long timeout, TimeUnit unit)
T	poll()
T	poll(long timeout, TimeUnit unit)
void	put(T t)
int	remainingCapacity()
boolean	remove(Object o)
T	take()

Methods inherited from class java.util.concurrent.ConcurrentLinkedQueue

add, addAll, clear, contains, forEach, isEmpty, iterator, peek, removeAll, removeIf, retainAll, size, spliterator, toArray, toArray, toString

Methods inherited from class java.util.AbstractQueue

element, remove

Methods inherited from class java.util.AbstractCollection

containsAll

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.concurrent.BlockingQueue

add, contains

Methods inherited from interface java.util.Collection

addAll, clear, containsAll, equals, hashCode, isEmpty, iterator, parallelStream, removeAll, removeIf, retainAll, size, spliterator, stream, toArray, toArray, toArray

Methods inherited from interface java.lang.Iterable

forEach

Methods inherited from interface java.util.Queue

element, peek, remove

Field Details

serialVersionUID

private static final long serialVersionUID

See Also:

• Constant Field Values

capacity

private final int capacity

lock

private final Lock lock

not_empty

private final Condition not_empty

waiting_takers

private final AtomicInteger waiting_takers

Constructor Details

ConcurrentLinkedBlockingQueue

public ConcurrentLinkedBlockingQueue(int capacity)

Method Details

offer

public boolean offer(T t)

Drops elements if capacity has been reached. That's OK for the ThreadPoolExecutor as dropped messages will get retransmitted

Specified by:

offer in interface BlockingQueue<T>

Specified by:

offer in interface Queue<T>

Overrides:

offer in class ConcurrentLinkedQueue<T>

Parameters:

t -

Returns:

take

public T take()
       throws InterruptedException

Specified by:

take in interface BlockingQueue<T>

Throws:

InterruptedException

poll

public T poll()

Specified by:

poll in interface Queue<T>

Overrides:

poll in class ConcurrentLinkedQueue<T>

poll

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

Specified by:

poll in interface BlockingQueue<T>

Throws:

InterruptedException

remove

public boolean remove(Object o)

Specified by:

remove in interface BlockingQueue<T>

Specified by:

remove in interface Collection<T>

Overrides:

remove in class ConcurrentLinkedQueue<T>

remainingCapacity

public int remainingCapacity()

Specified by:

remainingCapacity in interface BlockingQueue<T>

drainTo

public int drainTo(Collection<? super T> c)

Specified by:

drainTo in interface BlockingQueue<T>

put

public void put(T t)
         throws InterruptedException

Specified by:

put in interface BlockingQueue<T>

Throws:

InterruptedException

offer

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

Specified by:

offer in interface BlockingQueue<T>

Throws:

InterruptedException

drainTo

public int drainTo(Collection<? super T> c,
 int maxElements)

Specified by:

drainTo in interface BlockingQueue<T>