org.crosswire.common.activate
Class Activator

java.lang.Object
  org.crosswire.common.activate.Activator

public class Activator
extends Object

Manager for instances of Activatable. Activator should be used to manage all activate()ions and deactivate()ions so that it can keep a track of exactly what is active and what can be deactivate()d is save memory.

Distribution Licence:
JSword is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License, version 2 as published by the Free Software Foundation.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
The License is available on the internet here, or by writing to: Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
The copyright to this program is held by it's authors.

Version:

$Id: Activator.java,v 1.3 2005/03/19 01:57:01 dmsmith Exp $

Author:

Joe Walker [joe at eireneh dot com]

See Also:

Licence

Field Summary

private static Set	activated The list of things that we have activated
static int	KILL_EVERYTHING Try as hard as possible to conserve memory
static int	KILL_LEAST_USED Reduce memory usage, but only where sensible
static int	KILL_ONLY_IF_TIGHT Reduce memory usage, but only if we really need to
private static Lock	lock The object we use to prevent others from

Constructor Summary

private

Activator() Prevent instansiation

Method Summary

static void	activate(Activatable subject) Check that a subject is activated and call activate() if not.
static void	deactivate(Activatable subject) Deactivate an Activatable object.
static void	reduceMemoryUsage(int amount) If we need to tighten things up a bit we can save memory with this

Methods inherited from class java.lang.Object

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

Field Detail

KILL_EVERYTHING

public static final int KILL_EVERYTHING

Try as hard as possible to conserve memory

See Also:

Constant Field Values

KILL_LEAST_USED

public static final int KILL_LEAST_USED

Reduce memory usage, but only where sensible

See Also:

Constant Field Values

KILL_ONLY_IF_TIGHT

public static final int KILL_ONLY_IF_TIGHT

Reduce memory usage, but only if we really need to

See Also:

Constant Field Values

activated

private static Set activated

The list of things that we have activated

lock

private static Lock lock

The object we use to prevent others from

Constructor Detail

Activator

private Activator()

Prevent instansiation

Method Detail

activate

public static void activate(Activatable subject)

Check that a subject is activated and call activate() if not.

Parameters:

subject - The thing to activate

reduceMemoryUsage

public static void reduceMemoryUsage(int amount)

If we need to tighten things up a bit we can save memory with this

deactivate

public static void deactivate(Activatable subject)

Deactivate an Activatable object. It is safe to activate() something and then forget to deactivate() it since we keep a track of activated objects and will automatically deactivate() when needed, so this method should only be used when we are sure that something will not be needed again.

Parameters:

subject - The thing to de-activate