net.floodlightcontroller.flowcache
Class PriorityPendingQueue<E>

java.lang.Object
  net.floodlightcontroller.flowcache.PriorityPendingQueue<E>

public class PriorityPendingQueue<E>
extends java.lang.Object

PriorityPendingQueue class - This class is a variant implementation for PriorityBlockingQueue PriorityBlockingQueue implementation has two problems: 1. service for events with the same priority has no guarantee of FIFO sequence. This can be solved by override of comparator though. 2. PriorityBlockingQueue is implemented through heap, which has a O(log(n)) complexity for enqueue and dequeue operations. to get a O(1) complexity with enqueue and dequeue operations, we propose this PriorityPendingList class.

PriorityPendingQueue has three separate queues: High Priority, Medium Priority and Low Priority. the requirements here are: 1. dequeue from the Queue will always return the event with the highest priority 2. events with the same priority will be dequeued in their inserting order 3. enqueue and dequeue have O(1) complexity current only support offer() and take() methods

Author:

meiyang

Nested Class Summary

static class

PriorityPendingQueue.EventPriority

Constructor Summary

PriorityPendingQueue()

Method Summary

void	clear()
boolean	isEmpty()
boolean	offer(E e)
boolean	offer(E e, PriorityPendingQueue.EventPriority p)
E	peek()
E	poll()
int	size()
E	take()

Methods inherited from class java.lang.Object

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

Constructor Detail

PriorityPendingQueue

public PriorityPendingQueue()

Method Detail

take

public E take()
       throws java.lang.InterruptedException

Throws:

java.lang.InterruptedException

poll

public E poll()

peek

public E peek()

offer

public boolean offer(E e,
                     PriorityPendingQueue.EventPriority p)

offer

public boolean offer(E e)

size

public int size()

clear

public void clear()

isEmpty

public boolean isEmpty()