helpobservesubject.java

一个数据挖掘软件ALPHAMINERR的整个过程的JAVA版源代码

/*
 *    This program is free software; you can redistribute it and/or modify
 *    it under the terms of the GNU General Public License as published by
 *    the Free Software Foundation; either version 2 of the License, or
 *    (at your option) any later version.
 *
 *    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.
 *
 *    You should have received a copy of the GNU General Public License
 *    along with this program; if not, write to the Free Software
 *    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

package eti.bi.alphaminer.core.observer;

/**
 * @author kclai
 *
 * TODO To change the template for this generated type comment go to
 * Window - Preferences - Java - Code Style - Code Templates
 */

import java.util.Vector;

/**
 * HelpObserver is an abstract interface. It provides an interface to update 
 * the help state from a static HelpObserverSubject.
 */
public class HelpObserveSubject {
    private static HelpObserveSubject m_helpObserveSubject;
    private static Vector<HelpObserver> m_Observers = new Vector<HelpObserver>();
    
    public HelpObserveSubject() {
        if ( m_helpObserveSubject == null ) {
            m_helpObserveSubject = new HelpObserveSubject();
        }
    }
    
    public static void registerInterest(HelpObserver observer) {
        m_Observers.add(observer);
    }
    
    public static void unregisterInterest(HelpObserver observer) {
        m_Observers.remove(observer);
    }
    
    public static void sendNotify(boolean helpState) {
        for (int i=0; i<m_Observers.size(); i++) {
			m_Observers.elementAt(i).Update(helpState);
		}
    }
}