org.jboss.cache.eviction

Class LRUQueue

java.lang.Object

org.jboss.cache.eviction.LRUQueue

All Implemented Interfaces:

Iterable<NodeEntry>, EvictionQueue

public class LRUQueue
extends Object
implements EvictionQueue

LRU Eviction Queue implementation.

This eviction queue will iterate properly through two sorted lists. One sorted by maxAge and the other sorted by idleTime.

Version:

$Revision: 7168 $

Author:

Daniel Huang (dhuang@jboss.org)

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	LRUQueue()

Method Summary

Methods

Modifier and Type	Method and Description
void	addNodeEntry(NodeEntry entry) Add a NodeEntry to the queue.
void	clear() Clear the queue.
boolean	containsNodeEntry(NodeEntry entry) Check if queue contains the given NodeEntry.
NodeEntry	getFirstLRUNodeEntry()
NodeEntry	getFirstMaxAgeNodeEntry()
NodeEntry	getFirstNodeEntry() Get the first entry in the queue.
NodeEntry	getNodeEntry(Fqn fqn) Retrieve a node entry by Fqn.
NodeEntry	getNodeEntry(String fqn)
int	getNumberOfElements() Get the number of elements in the queue.
int	getNumberOfNodes() Get the number of nodes in the queue.
protected Iterator<NodeEntry>	iterateLRUQueue()
protected Iterator<NodeEntry>	iterateMaxAgeQueue()
Iterator<NodeEntry>	iterator()
void	modifyElementCount(int difference)
void	removeNodeEntry(NodeEntry entry) Remove a NodeEntry from queue.
protected void	removeNodeEntryFromLRU(NodeEntry entry)
protected void	removeNodeEntryFromMaxAge(NodeEntry entry)
protected void	reorderByLRU(Fqn fqn)

Methods inherited from class java.lang.Object

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

Constructor Detail

LRUQueue

protected LRUQueue()

Method Detail

reorderByLRU

protected void reorderByLRU(Fqn fqn)

getFirstNodeEntry

public NodeEntry getFirstNodeEntry()

Description copied from interface: EvictionQueue

Get the first entry in the queue.

If there are no entries in queue, this method will return null.

The first node returned is expected to be the first node to evict.

Specified by:

getFirstNodeEntry in interface EvictionQueue

Returns:

first NodeEntry in queue.

getFirstLRUNodeEntry

public NodeEntry getFirstLRUNodeEntry()

getFirstMaxAgeNodeEntry

public NodeEntry getFirstMaxAgeNodeEntry()

getNodeEntry

public NodeEntry getNodeEntry(Fqn fqn)

Description copied from interface: EvictionQueue

Retrieve a node entry by Fqn.

This will return null if the entry is not found.

Specified by:

getNodeEntry in interface EvictionQueue

Parameters:

fqn - Fqn of the node entry to retrieve.

Returns:

Node Entry object associated with given Fqn param.

getNodeEntry

public NodeEntry getNodeEntry(String fqn)

Specified by:

getNodeEntry in interface EvictionQueue

containsNodeEntry

public boolean containsNodeEntry(NodeEntry entry)

Description copied from interface: EvictionQueue

Check if queue contains the given NodeEntry.

Specified by:

containsNodeEntry in interface EvictionQueue

Parameters:

entry - NodeEntry to check for existence in queue.

Returns:

true/false if NodeEntry exists in queue.

removeNodeEntryFromLRU

protected void removeNodeEntryFromLRU(NodeEntry entry)

removeNodeEntryFromMaxAge

protected void removeNodeEntryFromMaxAge(NodeEntry entry)

removeNodeEntry

public void removeNodeEntry(NodeEntry entry)

Description copied from interface: EvictionQueue

Remove a NodeEntry from queue.

If the NodeEntry does not exist in the queue, this method will return normally.

Specified by:

removeNodeEntry in interface EvictionQueue

Parameters:

entry - The NodeEntry to remove from queue.

addNodeEntry

public void addNodeEntry(NodeEntry entry)

Description copied from interface: EvictionQueue

Add a NodeEntry to the queue.

Specified by:

addNodeEntry in interface EvictionQueue

Parameters:

entry - The NodeEntry to add to queue.

getNumberOfNodes

public int getNumberOfNodes()

Description copied from interface: EvictionQueue

Get the number of nodes in the queue.

Specified by:

getNumberOfNodes in interface EvictionQueue

Returns:

The number of nodes in the queue.

getNumberOfElements

public int getNumberOfElements()

Description copied from interface: EvictionQueue

Get the number of elements in the queue.

Specified by:

getNumberOfElements in interface EvictionQueue

Returns:

The number of elements in the queue.

clear

public void clear()

Description copied from interface: EvictionQueue

Clear the queue.

Specified by:

clear in interface EvictionQueue

modifyElementCount

public void modifyElementCount(int difference)

Specified by:

modifyElementCount in interface EvictionQueue

iterator

public Iterator<NodeEntry> iterator()

Specified by:

iterator in interface Iterable<NodeEntry>

iterateMaxAgeQueue

protected final Iterator<NodeEntry> iterateMaxAgeQueue()

iterateLRUQueue

protected final Iterator<NodeEntry> iterateLRUQueue()