001 /* ========================================================================
002 * JCommon : a free general purpose class library for the Java(tm) platform
003 * ========================================================================
004 *
005 * (C) Copyright 2000-2005, by Object Refinery Limited and Contributors.
006 *
007 * Project Info: http://www.jfree.org/jcommon/index.html
008 *
009 * This library is free software; you can redistribute it and/or modify it
010 * under the terms of the GNU Lesser General Public License as published by
011 * the Free Software Foundation; either version 2.1 of the License, or
012 * (at your option) any later version.
013 *
014 * This library is distributed in the hope that it will be useful, but
015 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
016 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
017 * License for more details.
018 *
019 * You should have received a copy of the GNU Lesser General Public
020 * License along with this library; if not, write to the Free Software
021 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
022 * USA.
023 *
024 * [Java is a trademark or registered trademark of Sun Microsystems, Inc.
025 * in the United States and other countries.]
026 *
027 * -----------------------
028 * ActionConcentrator.java
029 * -----------------------
030 * (C)opyright 2003, 2004, by Thomas Morgner and Contributors.
031 *
032 * Original Author: Thomas Morgner;
033 * Contributor(s): David Gilbert (for Object Refinery Limited);
034 *
035 * $Id: ActionConcentrator.java,v 1.3 2005/10/18 13:22:13 mungady Exp $
036 *
037 * Changes
038 * -------
039 * 24-Aug-2003 : Initial version
040 * 07-Jun-2004 : Corrected source headers (DG);
041 */
042
043 package org.jfree.ui.action;
044
045 import java.util.ArrayList;
046
047 import javax.swing.Action;
048
049 /**
050 * This class is used to collect actions to be enabled or disabled
051 * by a sinle call.
052 *
053 * @author Thomas Morgner
054 */
055 public class ActionConcentrator {
056
057 /** The collection used to store the actions of this concentrator. */
058 private final ArrayList actions;
059
060 /**
061 * DefaultConstructor.
062 */
063 public ActionConcentrator() {
064 this.actions = new ArrayList();
065 }
066
067 /**
068 * Adds the action to this concentrator.
069 *
070 * @param a the action to be added.
071 */
072 public void addAction(final Action a) {
073 if (a == null) {
074 throw new NullPointerException();
075 }
076 this.actions.add(a);
077 }
078
079 /**
080 * Removes the action from this concentrator.
081 *
082 * @param a the action to be removed.
083 */
084 public void removeAction(final Action a) {
085 if (a == null) {
086 throw new NullPointerException();
087 }
088 this.actions.remove(a);
089 }
090
091 /**
092 * Defines the state for all actions.
093 *
094 * @param b the new state for all actions.
095 */
096 public void setEnabled(final boolean b) {
097 for (int i = 0; i < this.actions.size(); i++) {
098 final Action a = (Action) this.actions.get(i);
099 a.setEnabled(b);
100 }
101 }
102
103 /**
104 * Returns, whether all actions are disabled.
105 * If one action is enabled, then this method will return
106 * true.
107 *
108 * @return true, if at least one action is enabled, false
109 * otherwise.
110 */
111 public boolean isEnabled() {
112 for (int i = 0; i < this.actions.size(); i++) {
113 final Action a = (Action) this.actions.get(i);
114 if (a.isEnabled()) {
115 return true;
116 }
117 }
118 return false;
119 }
120
121 }