    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
    043package org.jfree.ui.action;
    044
    045import java.util.ArrayList;
    046import 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 */
    054public 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}