javax.swing.undo

Interface UndoableEdit

Known Implementing Classes:
AbstractDocument.DefaultDocumentEvent, AbstractDocument.ElementEdit, AbstractUndoableEdit, CompoundEdit, DefaultStyledDocument.AttributeUndoableEdit, StateEdit, UndoManager

public interface UndoableEdit

An editing operation that supports undo/redoability.

Method Summary

boolean
addEdit(UndoableEdit edit)
Incorporates another editing action into this one, thus forming a combined action.
boolean
canRedo()
Determines whether it would be possible to redo this editing action.
boolean
canUndo()
Determines whether it would be possible to undo this editing action.
void
die()
Informs this edit action that it will no longer be used.
String
getPresentationName()
Returns a human-readable, localized name that describes this editing action and can be displayed to the user.
String
getRedoPresentationName()
Returns the redo presentation name.
String
getUndoPresentationName()
Returns the undo presentation name.
boolean
isSignificant()
Determines whether this editing action is significant enough for being seperately undoable by the user.
void
redo()
Redoes this editing action.
boolean
replaceEdit(UndoableEdit edit)
Incorporates another editing action into this one, thus forming a combined action that replaces the argument action.
void
undo()
Undoes this editing action.

Method Details

addEdit

public boolean addEdit(UndoableEdit edit)
Incorporates another editing action into this one, thus forming a combined action.
Parameters:
edit - the editing action to be incorporated.
Returns:
true if the edit was combined successfully, and false if it could not be combined.

canRedo

public boolean canRedo()
Determines whether it would be possible to redo this editing action.
Returns:
true to indicate that this action can be redone, false otherwise.
See Also:
redo(), canUndo()

canUndo

public boolean canUndo()
Determines whether it would be possible to undo this editing action.
Returns:
true to indicate that this action can be undone, false otherwise.
See Also:
undo(), canRedo()

die

public void die()
Informs this edit action that it will no longer be used. Some actions might use this information to release resources, for example open files. Called by UndoManager before this action is removed from the edit queue.

getPresentationName

public String getPresentationName()
Returns a human-readable, localized name that describes this editing action and can be displayed to the user.
Returns:
The presentation name.

getRedoPresentationName

public String getRedoPresentationName()
Returns the redo presentation name.
Returns:
The redo presentation name.

getUndoPresentationName

public String getUndoPresentationName()
Returns the undo presentation name.
Returns:
The undo presentation name.

isSignificant

public boolean isSignificant()
Determines whether this editing action is significant enough for being seperately undoable by the user. A typical significant action would be the resizing of an object. However, changing the selection in a text document would usually not be considered significant.
Returns:
true to indicate that the action is significant enough for being separately undoable, or false otherwise.

redo

public void redo()
            throws CannotRedoException
Redoes this editing action.
Throws:
CannotRedoException - if the edit cannot be undone.
See Also:
canRedo(), undo()

replaceEdit

public boolean replaceEdit(UndoableEdit edit)
Incorporates another editing action into this one, thus forming a combined action that replaces the argument action.
Parameters:
edit - the editing action to be replaced.
Returns:
true if the edit is successfully replaced, and false otherwise.

undo

public void undo()
            throws CannotUndoException
Undoes this editing action.
Throws:
CannotUndoException - if the edit cannot be undone.
See Also:
canUndo(), redo()

UndoableEdit.java -- Copyright (C) 2002, 2006, Free Software Foundation, Inc. This file is part of GNU Classpath. GNU Classpath is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version. GNU Classpath 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 General Public License for more details. You should have received a copy of the GNU General Public License along with GNU Classpath; see the file COPYING. If not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. Linking this library statically or dynamically with other modules is making a combined work based on this library. Thus, the terms and conditions of the GNU General Public License cover the whole combination. As a special exception, the copyright holders of this library give you permission to link this library with independent modules to produce an executable, regardless of the license terms of these independent modules, and to copy and distribute the resulting executable under terms of your choice, provided that you also meet, for each linked independent module, the terms and conditions of the license of that module. An independent module is a module which is not derived from or based on this library. If you modify this library, you may extend this exception to your version of the library, but you are not obligated to do so. If you do not wish to do so, delete this exception statement from your version.