001 /* AbstractSpinnerModel.java -- 002 Copyright (C) 2004, 2006, Free Software Foundation, Inc. 003 004 This file is part of GNU Classpath. 005 006 GNU Classpath is free software; you can redistribute it and/or modify 007 it under the terms of the GNU General Public License as published by 008 the Free Software Foundation; either version 2, or (at your option) 009 any later version. 010 011 GNU Classpath is distributed in the hope that it will be useful, but 012 WITHOUT ANY WARRANTY; without even the implied warranty of 013 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 014 General Public License for more details. 015 016 You should have received a copy of the GNU General Public License 017 along with GNU Classpath; see the file COPYING. If not, write to the 018 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 019 02110-1301 USA. 020 021 Linking this library statically or dynamically with other modules is 022 making a combined work based on this library. Thus, the terms and 023 conditions of the GNU General Public License cover the whole 024 combination. 025 026 As a special exception, the copyright holders of this library give you 027 permission to link this library with independent modules to produce an 028 executable, regardless of the license terms of these independent 029 modules, and to copy and distribute the resulting executable under 030 terms of your choice, provided that you also meet, for each linked 031 independent module, the terms and conditions of the license of that 032 module. An independent module is a module which is not derived from 033 or based on this library. If you modify this library, you may extend 034 this exception to your version of the library, but you are not 035 obligated to do so. If you do not wish to do so, delete this 036 exception statement from your version. */ 037 038 039 package javax.swing; 040 041 import java.util.EventListener; 042 043 import javax.swing.event.ChangeEvent; 044 import javax.swing.event.ChangeListener; 045 import javax.swing.event.EventListenerList; 046 047 /** 048 * Provides standard implementations for some of the methods in 049 * {@link SpinnerModel}. 050 * 051 * @since 1.4 052 * 053 * @author Ka-Hing Cheung 054 */ 055 public abstract class AbstractSpinnerModel implements SpinnerModel 056 { 057 private ChangeEvent changeEvent = new ChangeEvent(this); 058 059 /** Stores the listeners registered with the model. */ 060 protected EventListenerList listenerList = new EventListenerList(); 061 062 /** 063 * Creates an <code>AbstractSpinnerModel</code>. 064 */ 065 public AbstractSpinnerModel() 066 { 067 // Nothing to do here. 068 } 069 070 /** 071 * Registers a <code>ChangeListener</code> with the model so that it will 072 * receive {@link ChangeEvent} notifications when the model changes. 073 * 074 * @param listener the listener to add (<code>null</code> is ignored). 075 */ 076 public void addChangeListener(ChangeListener listener) 077 { 078 listenerList.add(ChangeListener.class, listener); 079 } 080 081 /** 082 * Gets all the listeners that are of a particular type. 083 * 084 * @param c the type of listener 085 * @return the listeners that are of the specific type 086 */ 087 public <T extends EventListener> T[] getListeners(Class<T> c) 088 { 089 return listenerList.getListeners(c); 090 } 091 092 /** 093 * Gets all the <code>ChangeListener</code>s. 094 * 095 * @return all the <code>ChangeListener</code>s 096 */ 097 public ChangeListener[] getChangeListeners() 098 { 099 return (ChangeListener[]) listenerList.getListeners(ChangeListener.class); 100 } 101 102 /** 103 * Remove a particular listener. 104 * 105 * @param listener the listener to remove 106 */ 107 public void removeChangeListener(ChangeListener listener) 108 { 109 listenerList.remove(ChangeListener.class, listener); 110 } 111 112 /** 113 * Fires a <code>ChangeEvent</code> to all the <code>ChangeListener</code>s 114 * added to this model 115 */ 116 protected void fireStateChanged() 117 { 118 ChangeListener[] listeners = getChangeListeners(); 119 120 for (int i = 0; i < listeners.length; ++i) 121 listeners[i].stateChanged(changeEvent); 122 } 123 }