Class BaseSortedEvictionAlgorithm

  extended by org.jboss.cache.eviction.BaseEvictionAlgorithm
      extended by org.jboss.cache.eviction.BaseSortedEvictionAlgorithm
All Implemented Interfaces:
Direct Known Subclasses:
ElementSizeAlgorithm, LFUAlgorithm

public abstract class BaseSortedEvictionAlgorithm
extends BaseEvictionAlgorithm

An abstract SortedEvictionAlgorithm.

This class supports early termination of the eviction queue processing. Because the eviction queue is sorted by first to evict to last to evict, when iterating the eviction queue, the first time a node is encountered that does not require eviction will terminate the loop early. This way we don't incur the full breadth of the O(n) = n operation everytime we need to check for eviction (defined by eviction poll time interval).

Daniel Huang - - 10/2005

Field Summary
Fields inherited from class org.jboss.cache.eviction.BaseEvictionAlgorithm
allowTombstones, cache, configuration, evictionActionPolicy, evictionAlgorithmConfig, evictionQueue, recycleQueue, regionFqn
Constructor Summary
Method Summary
protected  void processQueues(BlockingQueue<EvictionEvent> queue)
          Event processing for Evict/Add/Visiting of nodes.
protected  void resortEvictionQueue(boolean evictionQueueModified)
          This method is called to resort the queue after add or visit events have occurred.
Methods inherited from class org.jboss.cache.eviction.BaseEvictionAlgorithm
assignToRegion, canIgnoreEvent, emptyRecycleQueue, evict, evictCacheNode, getEvictionActionPolicy, getEvictionAlgorithmConfig, getEvictionQueue, getNextInQueue, initialize, isNodeInUseAndNotTimedOut, isYoungerThanMinimumTimeToLive, process, processAddedElement, processAddedNodes, processAddedNodes, processMarkInUseNodes, processRemovedElement, processRemovedNodes, processUnmarkInUseNodes, processVisitedNodes, prune, resetEvictionQueue, setEvictionActionPolicy, setupEvictionQueue, shouldEvictNode, toString
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
Methods inherited from interface org.jboss.cache.eviction.EvictionAlgorithm

Constructor Detail


public BaseSortedEvictionAlgorithm()
Method Detail


protected void processQueues(BlockingQueue<EvictionEvent> queue)
                      throws EvictionException
Description copied from class: BaseEvictionAlgorithm
Event processing for Evict/Add/Visiting of nodes.

- On AddEvents a new element is added into the eviction queue - On RemoveEvents, the removed element is removed from the eviction queue. - On VisitEvents, the visited node has its eviction statistics updated (idleTime, numberOfNodeVisists, etc..)

processQueues in class BaseEvictionAlgorithm
queue - queue to inspect
EvictionException - in the event of problems


protected void resortEvictionQueue(boolean evictionQueueModified)
This method is called to resort the queue after add or visit events have occurred.

If the parameter is true, the queue needs to be resorted. If it is false, the queue does not need resorting.

evictionQueueModified - True if the queue was added to or visisted during event processing.

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