AbstractCellEditor.java

/*
 * $Id$
 *
 * Copyright 1997, 1998 by Sun Microsystems, Inc.,
 * 901 San Antonio Road, Palo Alto, California, 94303, U.S.A.
 * All rights reserved.
 *
 * This software is the confidential and proprietary information
 * of Sun Microsystems, Inc. ("Confidential Information").  You
 * shall not disclose such Confidential Information and shall use
 * it only in accordance with the terms of the license agreement
 * you entered into with Sun.
 * 
 * The Swing Connection has given permission for the following code
 * to be freely used, modified and redistributed. However, since it
 * is example code, Sun does not support it and warns that it has not 
 * been as rigorously tested as Sun's product code.
 *
 * For further details, see The Swing Connection's Copyright Notice and 
 * Disclaimer at http://java.sun.com/products/jfc/tsc/page_2/page_2.html
 *
 * The articles upon which the TreeTable idea is based are located at 
 * http://java.sun.com/products/jfc/tsc/tech_topics/tech_topics.html
 */

package arlut.csd.ganymede.client;

import java.util.EventObject;

import javax.swing.CellEditor;
import javax.swing.event.CellEditorListener;
import javax.swing.event.ChangeEvent;
import javax.swing.event.EventListenerList;

/**
 * @version $Id$
 * 
 * A base class for CellEditors, providing default implementations for all 
 * methods in the CellEditor interface and support for managing a series 
 * of listeners. 
 *
 * @author Philip Milne
 */

public class AbstractCellEditor implements CellEditor {

    protected EventListenerList listenerList = new EventListenerList();

    public Object getCellEditorValue() { return null; }
    public boolean isCellEditable(EventObject e) { return true; }
    public boolean shouldSelectCell(EventObject anEvent) { return false; }
    public boolean stopCellEditing() { return true; }
    public void cancelCellEditing() {}

    public void addCellEditorListener(CellEditorListener l) {
        listenerList.add(CellEditorListener.class, l);
    }

    public void removeCellEditorListener(CellEditorListener l) {
        listenerList.remove(CellEditorListener.class, l);
    }

    /**
     * Notify all listeners that have registered interest for
     * notification on this event type.  
     * @see EventListenerList
     */
    protected void fireEditingStopped() {
        // Guaranteed to return a non-null array
        Object[] listeners = listenerList.getListenerList();
        // Process the listeners last to first, notifying
        // those that are interested in this event
        for (int i = listeners.length-2; i>=0; i-=2) {
            if (listeners[i]==CellEditorListener.class) {
                ((CellEditorListener)listeners[i+1]).editingStopped(new ChangeEvent(this));
            }          
        }
    }

    /**
     * Notify all listeners that have registered interest for
     * notification on this event type.  
     * @see EventListenerList
     */
    protected void fireEditingCanceled() {
        // Guaranteed to return a non-null array
        Object[] listeners = listenerList.getListenerList();
        // Process the listeners last to first, notifying
        // those that are interested in this event
        for (int i = listeners.length-2; i>=0; i-=2) {
            if (listeners[i]==CellEditorListener.class) {
                ((CellEditorListener)listeners[i+1]).editingCanceled(new ChangeEvent(this));
            }          
        }
    }
}