Visual Cafe 3/Visual Cafe 3.ISO/Vcafe/JFC.bin/AbstractListModel.java

Text File | 1998-06-30 | 5KB | 148 lines

/*
 * @(#)AbstractListModel.java    1.11 98/02/02
 *
 * Copyright (c) 1997 Sun Microsystems, Inc. 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.
 *
 * SUN MAKES NO REPRESENTATIONS OR WARRANTIES ABOUT THE SUITABILITY OF THE
 * SOFTWARE, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
 * PURPOSE, OR NON-INFRINGEMENT. SUN SHALL NOT BE LIABLE FOR ANY DAMAGES
 * SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR DISTRIBUTING
 * THIS SOFTWARE OR ITS DERIVATIVES.
 *
 */

package com.sun.java.swing;

import com.sun.java.swing.event.*;
import java.io.Serializable;

/**
 * The Abstract definition for the data model the provides
 * a List with its contents.
 * <p>
 * Warning: serialized objects of this class will not be compatible with
 * future swing releases.  The current serialization support is appropriate
 * for short term storage or RMI between Swing1.0 applications.  It will
 * not be possible to load serialized Swing1.0 objects with future releases
 * of Swing.  The JDK1.2 release of Swing will be the compatibility
 * baseline for the serialized form of Swing objects.
 */
public abstract class AbstractListModel implements ListModel, Serializable
{
    protected EventListenerList listenerList = new EventListenerList();


    /**
     * Add a listener to the list that's notified each time a change
     * to the data model occurs.
     * @param l the ListDataListener
     */
    public void addListDataListener(ListDataListener l) {
    listenerList.add(ListDataListener.class, l);
    }


    /**
     * Remove a listener from the list that's notified each time a
     * change to the data model occurs.
     * @param l the ListDataListener
     */
    public void removeListDataListener(ListDataListener l) {
    listenerList.remove(ListDataListener.class, l);
    }


    /**
     * AbstractListModel subclasses must call this method <b>after</b>
     * one or more elements of the list change.  The changed elements
     * are specified by a closed interval index0, index1, i.e. the
     * range that includes both index0 and index1.  Note that
     * index0 need not be less than or equal to index1.
     *
     * @param source The ListModel that changed, typically "this".
     * @param index0 One end of the new interval.
     * @param index1 The other end of the new interval.
     * @see EventListenerList
     * @see DefaultListModel
     */
    protected void fireContentsChanged(Object source, int index0, int index1)
    {
    Object[] listeners = listenerList.getListenerList();
    ListDataEvent e = null;

    for (int i = listeners.length - 2; i >= 0; i -= 2) {
        if (listeners[i] == ListDataListener.class) {
        if (e == null) {
            e = new ListDataEvent(this, ListDataEvent.CONTENTS_CHANGED, index0, index1);
        }
        ((ListDataListener)listeners[i+1]).contentsChanged(e);
        }
    }
    }


    /*
     * AbstractListModel subclasses must call this method <b>after</b>
     * one or more elements are added to the model.  The new elements
     * are specified by a closed interval index0, index1, i.e. the
     * range that includes both index0 and index1.  Note that
     * index0 need not be less than or equal to index1.
     *
     * @param source The ListModel that changed, typically "this".
     * @param index0 One end of the new interval.
     * @param index1 The other end of the new interval.
     * @see EventListenerList
     * @see DefaultListModel
     */
    protected void fireIntervalAdded(Object source, int index0, int index1)
    {
    Object[] listeners = listenerList.getListenerList();
    ListDataEvent e = null;

    for (int i = listeners.length - 2; i >= 0; i -= 2) {
        if (listeners[i] == ListDataListener.class) {
        if (e == null) {
            e = new ListDataEvent(this, ListDataEvent.INTERVAL_ADDED, index0, index1);
        }
        ((ListDataListener)listeners[i+1]).intervalAdded(e);
        }
    }
    }


    /*
     * AbstractListModel subclasses must call this method <b>after</b>
     * one or more elements are removed from the model.  The new elements
     * are specified by a closed interval index0, index1, i.e. the
     * range that includes both index0 and index1.  Note that
     * index0 need not be less than or equal to index1.
     *
     * @param source The ListModel that changed, typically "this".
     * @param index0 One end of the new interval.
     * @param index1 The other end of the new interval.
     * @see EventListenerList
     * @see DefaultListModel
     */
    protected void fireIntervalRemoved(Object source, int index0, int index1)
    {
    Object[] listeners = listenerList.getListenerList();
    ListDataEvent e = null;

    for (int i = listeners.length - 2; i >= 0; i -= 2) {
        if (listeners[i] == ListDataListener.class) {
        if (e == null) {
            e = new ListDataEvent(this, ListDataEvent.INTERVAL_REMOVED, index0, index1);
        }
        ((ListDataListener)listeners[i+1]).intervalRemoved(e);
        }
    }
    }
}