Package com.gigaspaces.events.fifo

Class BlockedOrderedQueue

java.lang.Object

com.gigaspaces.events.fifo.BlockedOrderedQueue

public class BlockedOrderedQueue
extends Object

BlockedOrderedQueue is a concurrent ordered queue that can deliver unordered events to a client in a FIFO order (using the event sequence number) the client is notified using a thread from the proxy's thread pool. the event dispensing / consumption algorithm is as follows: on ready event arrival: 1. push Msg to ready Queue 2. tryNotifyPooll() event onNotifyPool() // Task was added to pool 1. pop ready event from Queue 2. if event not null process event 3. if Queue not empty notifyPool() and exit // flag stays marked 4. set(flag, false) 5. if Queue not empty tryNotifyPool() // need to remark flag procedure tryNotifyPool() 1. CAS(flag,true) 2. if success notifyPool() procedure notifyPool() 1. Add Task(Queue) // this task can be saved with Queue and reuse

Since:

5.0

Version:

1.0

Author:

asy

Constructor Summary

Constructors

Constructor	Description
BlockedOrderedQueue(RemoteEventListener listener, ExecutorService threadPool, long maxCapacity, NotifyInfo info)	Constructor

Method Summary

Modifier and Type	Method	Description
RemoteEvent	dequeue()	Remove and return the next event in queue.
void	enqueue(RemoteEvent theEvent)	Add new event object to the queue.
void	interrupt()	This method interrupts all blocked threads awaiting on enqueue.
void	setInitialSeqNumbers(Map<Uuid,Long> initialSeqNumbers)

Methods inherited from class java.lang.Object

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

Constructor Details

BlockedOrderedQueue

public BlockedOrderedQueue(RemoteEventListener listener,
 ExecutorService threadPool,
 long maxCapacity,
 NotifyInfo info)

Constructor

Parameters:

maxCapacity - the maximum capacity of the queue

Method Details

enqueue

public void enqueue(RemoteEvent theEvent)

Add new event object to the queue. The operation will block if - the queue exceeded its maximum capacity and event sequence number exceeded the maximum sequence number in queue,

Parameters:

theEvent - the event to be enqueued

dequeue

public RemoteEvent dequeue()

Remove and return the next event in queue. If the queue is empty the method will block until an event arrives Note: This method is not concurrent and must be called from one thread only.

Returns:

the removed event

interrupt

public void interrupt()

This method interrupts all blocked threads awaiting on enqueue. This is usually called when the Queue is no longer needed and should be discarded.

setInitialSeqNumbers

public void setInitialSeqNumbers(Map<Uuid,Long> initialSeqNumbers)

Parameters:

initialSeqNumbers - the initialSeqNumbers to set