/* $Id: AbstractActionCheckBoxMenuItem.java 17865 2010-01-12 20:45:26Z linus $

  *****************************************************************************

  * Copyright (c) 2009 Contributors - see below

  * All rights reserved. This program and the accompanying materials

  * are made available under the terms of the Eclipse Public License v1.0

  * which accompanies this distribution, and is available at

  * http://www.eclipse.org/legal/epl-v10.html

  *

  * Contributors:

  *    bobtarling

  *****************************************************************************

  *

  * Some portions of this file was previously release using the BSD License:

  */

 // Copyright (c) 2005-2006 The Regents of the University of California. All

 // Rights Reserved. Permission to use, copy, modify, and distribute this

 // software and its documentation without fee, and without a written

 // agreement is hereby granted, provided that the above copyright notice

 // and this paragraph appear in all copies.  This software program and

 // documentation are copyrighted by The Regents of the University of

 // California. The software program and documentation are supplied "AS

 // IS", without any accompanying services from The Regents. The Regents

 // does not warrant that the operation of the program will be

 // uninterrupted or error-free. The end-user understands that the program

 // was developed for research purposes and is advised not to rely

 // exclusively on the program for any reason.  IN NO EVENT SHALL THE

 // UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY FOR DIRECT, INDIRECT,

 // SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING LOST PROFITS,

 // ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF

 // THE UNIVERSITY OF CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF

 // SUCH DAMAGE. THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY

 // WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF

 // MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE

 // PROVIDED HEREUNDER IS ON AN "AS IS" BASIS, AND THE UNIVERSITY OF

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 // UPDATES, ENHANCEMENTS, OR MODIFICATIONS.

 package org.argouml.uml.diagram.ui;

 import java.awt.event.ActionEvent;

 import java.util.Iterator;

 import javax.swing.Action;

 import org.argouml.i18n.Translator;

 import org.argouml.ui.targetmanager.TargetManager;

 import org.argouml.ui.UndoableAction;

 /**

  * This class adds the common algorithms

  * for handling multiple targets

  * for a checkbox menuitem to the UMLAction.

  *

  * @author mvw@tigris.org

  */

 abstract class AbstractActionCheckBoxMenuItem extends UndoableAction {

     /**

      * @param key the name (to be localized)

      */

     public AbstractActionCheckBoxMenuItem(String key) {

         super(Translator.localize(key), null);

         // Set the tooltip string:

         putValue(Action.SHORT_DESCRIPTION, 

                 Translator.localize(key));

     }

     /**

      * This action should be enabled when: <ul>

      * <li>all targets are modelelements that support this checkmark and

      * <li>all targets have the checkmark either on or off

      *     (mixed is not yet supported, but could be if a tri-state

      *     checkmark is implemented).

      * </ul>

      */

     public boolean isEnabled() {

         boolean result = true;

         boolean commonValue = true; // only initialized to prevent warning

         boolean first = true;

         Iterator i = TargetManager.getInstance().getTargets().iterator();

         while (i.hasNext() && result) {

             Object t = i.next();

             try {

                 boolean value = valueOfTarget(t);

                 if (first) {

                     commonValue = value;

                     first = false;

                 }

                 result &= (commonValue == value);

             } catch (IllegalArgumentException e) {

                 result = false; //not supported for this target

             }

         }

         return result;

     }

     /**

      * @param t the target modelelement

      * @return the value of the checkmark for this modelelement

      */

     abstract boolean valueOfTarget(Object t);

     /**

      * This action is performed on ALL targets.

      *

      * @see java.awt.event.ActionListener#actionPerformed(java.awt.event.ActionEvent)

      */

     public final void actionPerformed(ActionEvent e) {

         super.actionPerformed(e);

         Iterator i = TargetManager.getInstance().getTargets().iterator();

         while (i.hasNext()) {

             Object t = i.next();

             toggleValueOfTarget(t);

         }

     }

     /**

      * @param t the target modelelement

      */

     abstract void toggleValueOfTarget(Object t);

 }