net.fortytwo.stream.shj

Class ExpirationManager<T extends Expirable>

java.lang.Object

net.fortytwo.stream.shj.ExpirationManager<T>

All Implemented Interfaces:

Index<T>

public abstract class ExpirationManager<T extends Expirable>
extends java.lang.Object
implements Index<T>

A manager for items which may expire over time. It is assumed that the items (i.e. both their hashCodes and their expiration times) are immutable; the only exception is the action of turning a solution into a "tombstone". It is also assumed that identical solutions will not be added; a solution must be removed, or must expire, before being added again (e.g. to update its expiration time). Finally, only non-tombstone items may be added.

Author:

Joshua Shinavier (http://fortytwo.net)

Constructor Summary

Constructors

Constructor and Description
ExpirationManager()

Method Summary

Modifier and Type	Method and Description
void	add(T toAdd) Adds an item.
void	clear() Removes all data at once.
int	evictExpired()
int	getHeapSize()
protected abstract long	getNow()
boolean	isEmpty()
void	notifyFinishedAdding()
boolean	remove(T toRemove) Removes the given item from this index
void	setVerbose(boolean verbose)
void	start()
void	stop()

Methods inherited from class java.lang.Object

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

Constructor Detail

ExpirationManager

public ExpirationManager()

Method Detail

getNow

protected abstract long getNow()

isEmpty

public boolean isEmpty()

Specified by:

isEmpty in interface Index<T extends Expirable>

clear

public void clear()

Description copied from interface: Index

Removes all data at once. It can be assumed that the data is no longer needed; this operation resets the index and releases the data for garbage collection.

Specified by:

clear in interface Index<T extends Expirable>

add

public void add(T toAdd)

Adds an item. It is assumed that the item is not already present. The time complexity of this operation is O(log(n)), from PriorityQueue.add

Specified by:

add in interface Index<T extends Expirable>

Parameters:

toAdd - the item to add

remove

public boolean remove(T toRemove)

Description copied from interface: Index

Removes the given item from this index

Specified by:

remove in interface Index<T extends Expirable>

Parameters:

toRemove - the item to remove

Returns:

whether an item was removed

notifyFinishedAdding

public void notifyFinishedAdding()

evictExpired

public int evictExpired()

start

public void start()

stop

public void stop()

getHeapSize

public int getHeapSize()

setVerbose

public void setVerbose(boolean verbose)