/*******************************************************************************
* CogTool Copyright Notice and Distribution Terms
* CogTool 1.3, Copyright (c) 2005-2013 Carnegie Mellon University
* This software is distributed under the terms of the FSF Lesser
* Gnu Public License (see LGPL.txt).
*
* CogTool is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation; either version 2.1 of the License, or
* (at your option) any later version.
*
* CogTool is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with CogTool; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
* CogTool makes use of several third-party components, with the
* following notices:
*
* Eclipse SWT version 3.448
* Eclipse GEF Draw2D version 3.2.1
*
* Unless otherwise indicated, all Content made available by the Eclipse
* Foundation is provided to you under the terms and conditions of the Eclipse
* Public License Version 1.0 ("EPL"). A copy of the EPL is provided with this
* Content and is also available at http://www.eclipse.org/legal/epl-v10.html.
*
* CLISP version 2.38
*
* Copyright (c) Sam Steingold, Bruno Haible 2001-2006
* This software is distributed under the terms of the FSF Gnu Public License.
* See COPYRIGHT file in clisp installation folder for more information.
*
* ACT-R 6.0
*
* Copyright (c) 1998-2007 Dan Bothell, Mike Byrne, Christian Lebiere &
* John R Anderson.
* This software is distributed under the terms of the FSF Lesser
* Gnu Public License (see LGPL.txt).
*
* Apache Jakarta Commons-Lang 2.1
*
* This product contains software developed by the Apache Software Foundation
* (http://www.apache.org/)
*
* jopt-simple version 1.0
*
* Copyright (c) 2004-2013 Paul R. Holser, Jr.
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
* LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*
* Mozilla XULRunner 1.9.0.5
*
* The contents of this file are subject to the Mozilla Public License
* Version 1.1 (the "License"); you may not use this file except in
* compliance with the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/.
* Software distributed under the License is distributed on an "AS IS"
* basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See the
* License for the specific language governing rights and limitations
* under the License.
*
* The J2SE(TM) Java Runtime Environment version 5.0
*
* Copyright 2009 Sun Microsystems, Inc., 4150
* Network Circle, Santa Clara, California 95054, U.S.A. All
* rights reserved. U.S.
* See the LICENSE file in the jre folder for more information.
******************************************************************************/
package edu.cmu.cs.hcii.cogtool.util;
/**
* "Empty" implementation of IUndoableEdit.
* <p>
* Defaults to: (a) not being able to absorb other edits; (b) prefixing
* the edit's description by the localized strings for "Undo" and "Redo";
* (c) being significant.
* <p>
* Also provides basic strategy for maintaining whether the edit is
* active and whether it is in the state of having been done (and ready
* to be "undone") or undone (and ready to be "re-done").
*
* @author mlh
* @see javax.swing.undo.AbstractUndoableEdit
*/
public abstract class AUndoableEdit implements IUndoableEdit
{
/**
* Tracks whether <code>die</code> has been called.
*/
protected boolean active = true;
/**
* Tracks whether <code>undo</code> or <code>redo</code> is
* appropriate; calling either more than once in succession
* causes the appropriate exception to be thrown.
*/
protected boolean hasBeenDone = true;
/**
* The ListenerIdentifier this undoable edit is for.
*/
protected ListenerIdentifier lid;
/**
* The manager that "owns" this edit
*/
protected UndoManager owningMgr = null;
/**
* Constructor, initializing the associated ListenerIdentifier.
*
* @param listenerID the lid for this undoable edit.
*/
public AUndoableEdit(ListenerIdentifier listenerID)
{
lid = listenerID;
}
/**
* Fetch the ListenerIdentifier this undoable edit supports.
*/
public ListenerIdentifier getLID()
{
return lid;
}
/**
* Fetch the presentation string describing the nature of this edit.
* <p>
* If there is no description, the empty string ("") is returned.
* <p>
* Returns the empty string ("") as default behavior.
*
* @return the presentation description of this edit,
* if one exists; the empty string ("") otherwise
* @author mlh
*/
public String getPresentationName()
{
return "";
}
/**
* Fetch the presentation string describing the nature of this edit when
* it is poised to be re-done.
* <p>
* Prefixes the result of <code>L10N.get("UNDO.Redo", "Redo")</code>
* onto <code>getPresentationName()</code>.
*
* @return the presentation description of this edit when
* poised to be re-done
* @author mlh
*/
public String getRedoPresentationName()
{
String description = getPresentationName();
if ((description != null) && (description != "")) {
return L10N.get("REDO", "Redo") + ' ' + description;
}
return L10N.get("UNDO.Redo", "Redo");
}
/**
* Fetch the presentation string describing the nature of this edit when
* it is poised to be undone.
* <p>
* Prefixes the result of <code>L10N.get("UNDO.Undo", "Undo")</code>
* onto <code>getPresentationName()</code>.
*
* @return the presentation description of this edit when
* poised to be undone
* @author mlh
*/
public String getUndoPresentationName()
{
String description = getPresentationName();
if ((description != null) && (description != "")) {
return L10N.get("UNDO", "Undo") + ' ' + description;
}
return L10N.get("UNDO.Undo", "Undo");
}
/**
* Indicate whether this edit is "significant" (to be decided, ultimately,
* by the application).
* <p>
* Uniformly returns <code>true</code> by default.
*
* @return the indication of significance
* @author mlh
*/
public boolean isSignificant()
{
return true;
}
/**
* Make this edit inactive and recover any resources being held.
* <p>
* By default, simply records that the edit is no longer active.
*
* @author mlh
*/
public void die()
{
active = false;
}
/**
* Indicate whether this edit is currently active.
*
* @return true iff <code>die</code> has <b>not</b> been called
* on this instance
* @author mlh
*/
public boolean isActive()
{
return active;
}
/**
* Indicate whether this edit supports the <code>redo</code> operation
* after it has been undone.
* <p>
* By default, returns <code>true</code> iff the edit is still active
* and it is in the "not done" state.
*
* @return true iff it is allowed to invoke <code>redo</code>
* on this instance after invoking <code>undo</code>
* @author mlh
*/
public boolean canRedo()
{
return active && ! hasBeenDone;
}
/**
* Perform the actions necessary to reestablish the application state
* that should exist after this edit was done.
* <p>
* If <code>canRedo</code> returns <code>true</true>, resets the
* internal state to reflect that the edit has been "done".
* <p>
* Otherwise, throws the exception.
*
* @exception <code>CannotRedoException</code>
* if the redo is not possible
* @author mlh
*/
public void redo()
{
if (canRedo()) {
hasBeenDone = true;
}
else {
throw new CannotRedoException();
}
}
/**
* Perform the actions necessary to reestablish the application state
* that existed before this edit was done.
* <p>
* Throws the exception if the edit is not active or is in the
* "not done" state (that is, <code>undo</code> was the last call
* on this instance).
* <p>
* Otherwise, sets the internal state to indicate the edit is "not done".
*
* @exception <code>CannotUndoException</code>
* if the undo is not possible
* @author mlh
*/
public void undo()
{
if (canUndo()) {
hasBeenDone = false;
}
else {
throw new CannotUndoException();
}
}
/**
* Indicate whether the edit is "done" (i.e., hasn't been undone at all
* or has currently been re-done).
*/
public boolean isDone()
{
return hasBeenDone;
}
/**
* Get undo manager that "owns" this edit.
*/
public UndoManager getManager()
{
return owningMgr;
}
/**
* Set the undo manager that "owns" this edit.
*/
public void setManager(UndoManager mgr)
{
owningMgr = mgr;
}
public boolean canUndo()
{
return active && hasBeenDone;
}
}