com.partnersoft.gadgets
Class HashedCache

java.lang.Object
  com.partnersoft.gadgets.HashedCache

public abstract class HashedCache
extends java.lang.Object

A fixed-size caching implementation based on a hashed index.

Author:

Paul Reavis Copyright 1998 Partner Software, Inc.

Field Summary

static int

DEFAULTSIZE

Constructor Summary

HashedCache()
Create a hashed cache of the default size, 42.

HashedCache(int size)
Create a hashed cache of the desired size.

Method Summary

void	clear() Clears all items from the cache, so that they must be reloaded.
void	finalize(java.lang.Object flushCandidate) Optional override for subclasses - called before flushing an object.
java.lang.Object	getCached(java.lang.Object index)
int	getCacheSize()
abstract java.lang.Object	getUncached(java.lang.Object index) Subclasses must implement this - it does the "real fetch" of the object, uncached, however appropriate for your use.
boolean	getUsingSeparateReaperThread() If true, creates a separate thread which reaps old entries from the cache.
boolean	isFlushable(java.lang.Object flushCandidate) Optional override for subclasses - tests if an object can be flushed.
boolean	remove(java.lang.Object index)
void	setCacheSize(int newSize)
void	setUsingSeparateReaperThread(boolean tizit)

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULTSIZE

public static final int DEFAULTSIZE

See Also:

Constant Field Values

Constructor Detail

HashedCache

public HashedCache()

Create a hashed cache of the default size, 42.

HashedCache

public HashedCache(int size)

Create a hashed cache of the desired size.

Method Detail

getCached

public java.lang.Object getCached(java.lang.Object index)

finalize

public void finalize(java.lang.Object flushCandidate)

Optional override for subclasses - called before flushing an object. Does nothing by default.

isFlushable

public boolean isFlushable(java.lang.Object flushCandidate)

Optional override for subclasses - tests if an object can be flushed. Returns true by default.

getUncached

public abstract java.lang.Object getUncached(java.lang.Object index)

Subclasses must implement this - it does the "real fetch" of the object, uncached, however appropriate for your use. getCached() calls this method when it misses.

clear

public void clear()

Clears all items from the cache, so that they must be reloaded.

getCacheSize

public int getCacheSize()

setCacheSize

public void setCacheSize(int newSize)

getUsingSeparateReaperThread

public boolean getUsingSeparateReaperThread()

If true, creates a separate thread which reaps old entries from the cache. If false, reaping is done whenever new items are added.

setUsingSeparateReaperThread

public void setUsingSeparateReaperThread(boolean tizit)

remove

public boolean remove(java.lang.Object index)