org.jclouds.concurrent
Class DynamicThreadPoolExecutor.DynamicQueue<E>

java.lang.Object
  java.util.AbstractCollection<E>
      java.util.AbstractQueue<E>
          java.util.concurrent.LinkedBlockingQueue<E>
              org.jclouds.concurrent.DynamicThreadPoolExecutor.DynamicQueue<E>

All Implemented Interfaces:

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

Enclosing class:

DynamicThreadPoolExecutor

public static class DynamicThreadPoolExecutor.DynamicQueue<E>
extends LinkedBlockingQueue<E>

Much like a SynchronousQueue which acts as a rendezvous channel. It is well suited for handoff designs, in which a tasks is only queued if there is an available thread to pick it up.

This queue is correlated with a thread-pool, and allows insertions to the queue only if there is a free thread that can poll this task. Otherwise, the task is rejected and the decision is left up to one of the RejectedExecutionHandler policies:

1. DynamicThreadPoolExecutor.ForceQueuePolicy - forces the queue to accept the rejected task.
2. DynamicThreadPoolExecutor.TimedBlockingPolicy - waits for a given time for the task to be executed.

Author:

kimchy (Shay Banon)

See Also:

Serialized Form

Constructor Summary

DynamicThreadPoolExecutor.DynamicQueue()
Creates a DynamicQueue with a capacity of Integer.MAX_VALUE.

DynamicThreadPoolExecutor.DynamicQueue(int capacity)
Creates a DynamicQueue with the given (fixed) capacity.

Method Summary

boolean	offer(E o) Inserts the specified element at the tail of this queue if there is at least one available thread to run the current task.
void	setThreadPoolExecutor(ThreadPoolExecutor executor) Sets the executor this queue belongs to.

Methods inherited from class java.util.concurrent.LinkedBlockingQueue

clear, drainTo, drainTo, iterator, offer, peek, poll, poll, put, remainingCapacity, remove, size, take, toArray, toArray, toString

Methods inherited from class java.util.AbstractQueue

add, addAll, element, remove

Methods inherited from class java.util.AbstractCollection

contains, containsAll, isEmpty, removeAll, retainAll

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.Queue

element, remove

Methods inherited from interface java.util.Collection

addAll, containsAll, equals, hashCode, isEmpty, removeAll, retainAll

Constructor Detail

DynamicThreadPoolExecutor.DynamicQueue

public DynamicThreadPoolExecutor.DynamicQueue()

Creates a DynamicQueue with a capacity of Integer.MAX_VALUE.

DynamicThreadPoolExecutor.DynamicQueue

public DynamicThreadPoolExecutor.DynamicQueue(int capacity)

Creates a DynamicQueue with the given (fixed) capacity.

Parameters:

capacity - the capacity of this queue.

Method Detail

setThreadPoolExecutor

public void setThreadPoolExecutor(ThreadPoolExecutor executor)

Sets the executor this queue belongs to.

offer

public boolean offer(E o)

Inserts the specified element at the tail of this queue if there is at least one available thread to run the current task. If all pool threads are actively busy, it rejects the offer.

Specified by:

offer in interface BlockingQueue<E>

Specified by:

offer in interface Queue<E>

Overrides:

offer in class LinkedBlockingQueue<E>

Parameters:

o - the element to add.

Returns:

true if it was possible to add the element to this queue, else false

See Also:

ThreadPoolExecutor.execute(Runnable)