    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 1.4 2007/11/02 17:50:36 taqua 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    import javax.swing.Action;
    047
    048    /**
    049     * This class is used to collect actions to be enabled or disabled
    050     * by a sinle call.
    051     *
    052     * @author Thomas Morgner
    053     */
    054    public class ActionConcentrator {
    055
    056        /** The collection used to store the actions of this concentrator. */
    057        private final ArrayList actions;
    058
    059        /**
    060         * DefaultConstructor.
    061         */
    062        public ActionConcentrator() {
    063            this.actions = new ArrayList();
    064        }
    065
    066        /**
    067         * Adds the action to this concentrator.
    068         *
    069         * @param a the action to be added.
    070         */
    071        public void addAction(final Action a) {
    072            if (a == null) {
    073                throw new NullPointerException();
    074            }
    075            this.actions.add(a);
    076        }
    077
    078        /**
    079         * Removes the action from this concentrator.
    080         *
    081         * @param a the action to be removed.
    082         */
    083        public void removeAction(final Action a) {
    084            if (a == null) {
    085                throw new NullPointerException();
    086            }
    087            this.actions.remove(a);
    088        }
    089
    090        /**
    091         * Defines the state for all actions.
    092         *
    093         * @param b the new state for all actions.
    094         */
    095        public void setEnabled(final boolean b) {
    096            for (int i = 0; i < this.actions.size(); i++) {
    097                final Action a = (Action) this.actions.get(i);
    098                a.setEnabled(b);
    099            }
    100        }
    101
    102        /**
    103         * Returns, whether all actions are disabled.
    104         * If one action is enabled, then this method will return
    105         * true.
    106         *
    107         * @return true, if at least one action is enabled, false
    108         * otherwise.
    109         */
    110        public boolean isEnabled() {
    111            for (int i = 0; i < this.actions.size(); i++) {
    112                final Action a = (Action) this.actions.get(i);
    113                if (a.isEnabled()) {
    114                    return true;
    115                }
    116            }
    117            return false;
    118        }
    119
    120    }