root / import / ext3D / trunk / install-extension3d / IzPack / src / lib / com / izforge / izpack / util / Housekeeper.java @ 15280
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/*
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* $Id: Housekeeper.java,v 1.1 2006/06/14 07:29:07 cesar Exp $
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* IzPack
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* Copyright (C) 2002 by Elmar Grom
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*
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* File : Housekeeper.java
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* Description : Performs housekeeping and cleanup tasks for IzForge
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* Author's email : elmar@grom.net
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* Website : http://www.izforge.com
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version 2
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* of the License, or any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
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*/
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package com.izforge.izpack.util; |
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import java.util.Vector; |
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/*---------------------------------------------------------------------------*/
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/**
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* This class performs housekeeping and cleanup tasks. There can only be one
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* instance of <code>Housekeeper</code> per Java runtime, therefore this class
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* is implemented as a 'Singleton'.
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* <br><br>
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* It is VERY important to perform pre-shutdown cleanup operations through
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* this class. Do NOT rely on operations like <code>deleteOnExit()</code>
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* shutdown hooks or <code>finalize()</code>for cleanup. Because
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* <code>shutDown()</code> uses <code>System.exit()</code> to terminate,
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* these methods will not work at all or will not work reliably.
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*
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* @version 0.0.1 / 2/9/02
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* @author Elmar Grom
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*/
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/*---------------------------------------------------------------------------*/
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public class Housekeeper |
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{ |
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// ------------------------------------------------------------------------
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// Variable Declarations
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// ------------------------------------------------------------------------
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private static Housekeeper me = null; |
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private Vector cleanupClients = new Vector (); |
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/*--------------------------------------------------------------------------*/
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/**
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* This class is implemented as a 'Singleton'. Therefore the constructor is
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* private to prevent instantiation of this class. Use <code>getInstance()</code>
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* to obtain an instance for use.
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* <br><br>
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* For more information about the 'Singleton' pattern I highly recommend
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* the book Design Patterns by Gamma, Helm, Johnson and Vlissides
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* ISBN 0-201-63361-2.
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*/
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/*--------------------------------------------------------------------------*/
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private Housekeeper () {}
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/*--------------------------------------------------------------------------*/
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/**
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* Returns an instance of <code>Housekeeper</code> to use.
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*
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* @return an instance of <code>Housekeeper</code>.
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*/
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/*--------------------------------------------------------------------------*/
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public static Housekeeper getInstance () |
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{ |
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if (me == null) |
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{ |
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me = new Housekeeper ();
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} |
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return (me);
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} |
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/*--------------------------------------------------------------------------*/
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/**
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* Use to register objects that need to perform cleanup operations before the
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* application shuts down.
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*
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* @param client reference of to an object that needs to perform
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* cleanup operations.
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*/
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/*--------------------------------------------------------------------------*/
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public void registerForCleanup (CleanupClient client) |
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{ |
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cleanupClients.add (client); |
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} |
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/*--------------------------------------------------------------------------*/
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/**
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* This methods shuts the application down. First, it will call all clients
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* that have registered for cleanup operations. Once this has been
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* accomplished, the application will be forceably terminated.
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* <br><br>
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* <b>THIS METHOD DOES NOT RETURN!</b>
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*
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* @param exitCode the exit code that should be returned to the
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* calling process.
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*/
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/*--------------------------------------------------------------------------*/
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public void shutDown (int exitCode) |
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{ |
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for (int i = 0; i < cleanupClients.size (); i++) |
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{ |
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try
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{ |
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((CleanupClient)cleanupClients.elementAt (i)).cleanUp (); |
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} |
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catch (Throwable exception) |
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{ |
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// At this point we can not afford to treat exceptions. Cleanup that
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// can not be completed might unfortunately leave some garbage behind.
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// If we have a logging module, any exceptions received here should
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// be written to the log.
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} |
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} |
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System.exit (exitCode);
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} |
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} |
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/*---------------------------------------------------------------------------*/
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