servercomponent.java

Java的面向对象数据库系统的源代码

// You can redistribute this software and/or modify it under the terms of
// the Ozone Core License version 1 published by ozone-db.org.
//
// The original code and portions created by SMB are
// Copyright (C) 1997-@year@ by SMB GmbH. All rights reserved.
//
// $Id: ServerComponent.java,v 1.3 2002/09/18 06:54:15 per_nyfelt Exp $

package org.ozoneDB.core;


/**
 * Base class for all componente of the ozone core.<p>
 *
 * ServerComponent basically provides method to start/stop the component and to
 * check the internal state of the component. Each component has to properly
 * call the {@link #setChanged()} method in this regard.
 *
 * @author <a href="http://www.softwarebuero.de/">SMB</a>
 * @version $Revision: 1.3 $Date: 2002/09/18 06:54:15 $
 */
public abstract class ServerComponent {

    protected transient Env	env;

    private boolean		hasChanged;


    public ServerComponent( Env env ) {
        this.env = env;
    }


    public synchronized void setChanged() {
        this.hasChanged = true;
        env.storeSetup();
    }


    public boolean hasChanged() {
        return this.hasChanged;
    }


    public synchronized void clearChanged() {
        this.hasChanged = false;
    }

    /**
     * Start up and load the internal state from the server state properties.
     */
    public abstract void startup() throws Exception;

    public abstract void shutdown() throws Exception;


    /**
     * Save the internal state in the state to the server state properties.
     */
    public abstract void save() throws Exception;

}