/* * Copyright (c) 1997, 2006, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code 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 * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */package javax.swing.undo;import java.io.Serializable;import javax.swing.UIManager;/** * An abstract implementation of <code>UndoableEdit</code>, * implementing simple responses to all boolean methods in * that interface. * * @author Ray Ryan */public class AbstractUndoableEdit implements UndoableEdit, Serializable { /** * String returned by <code>getUndoPresentationName</code>; * as of Java 2 platform v1.3.1 this field is no longer used. This value * is now localized and comes from the defaults table with key * <code>AbstractUndoableEdit.undoText</code>. * * @see javax.swing.UIDefaults */ protected static final String UndoName = "Undo"; /** * String returned by <code>getRedoPresentationName</code>; * as of Java 2 platform v1.3.1 this field is no longer used. This value * is now localized and comes from the defaults table with key * <code>AbstractUndoableEdit.redoText</code>. * * @see javax.swing.UIDefaults */ protected static final String RedoName = "Redo"; /** * Defaults to true; becomes false if this edit is undone, true * again if it is redone. */ boolean hasBeenDone; /** * True if this edit has not received <code>die</code>; defaults * to <code>true</code>. */ boolean alive; /** * Creates an <code>AbstractUndoableEdit</code> which defaults * <code>hasBeenDone</code> and <code>alive</code> to <code>true</code>. */ public AbstractUndoableEdit() { super(); hasBeenDone = true; alive = true; } /** * Sets <code>alive</code> to false. Note that this * is a one way operation; dead edits cannot be resurrected. * Sending <code>undo</code> or <code>redo</code> to * a dead edit results in an exception being thrown. * * <p>Typically an edit is killed when it is consolidated by * another edit's <code>addEdit</code> or <code>replaceEdit</code> * method, or when it is dequeued from an <code>UndoManager</code>. */ public void die() { alive = false; } /** * Throws <code>CannotUndoException</code> if <code>canUndo</code> * returns <code>false</code>. Sets <code>hasBeenDone</code> * to <code>false</code>. Subclasses should override to undo the * operation represented by this edit. Override should begin with * a call to super. * * @exception CannotUndoException if <code>canUndo</code> * returns <code>false</code> * @see #canUndo */ public void undo() throws CannotUndoException { if (!canUndo()) { throw new CannotUndoException(); } hasBeenDone = false; } /** * Returns true if this edit is <code>alive</code> * and <code>hasBeenDone</code> is <code>true</code>. * * @return true if this edit is <code>alive</code> * and <code>hasBeenDone</code> is <code>true</code> * * @see #die * @see #undo * @see #redo */ public boolean canUndo() { return alive && hasBeenDone; } /** * Throws <code>CannotRedoException</code> if <code>canRedo</code> * returns false. Sets <code>hasBeenDone</code> to <code>true</code>. * Subclasses should override to redo the operation represented by * this edit. Override should begin with a call to super. * * @exception CannotRedoException if <code>canRedo</code> * returns <code>false</code> * @see #canRedo */ public void redo() throws CannotRedoException { if (!canRedo()) { throw new CannotRedoException(); } hasBeenDone = true; } /** * Returns <code>true</code> if this edit is <code>alive</code> * and <code>hasBeenDone</code> is <code>false</code>. * * @return <code>true</code> if this edit is <code>alive</code> * and <code>hasBeenDone</code> is <code>false</code> * @see #die * @see #undo * @see #redo */ public boolean canRedo() { return alive && !hasBeenDone; } /** * This default implementation returns false. * * @param anEdit the edit to be added * @return false * * @see UndoableEdit#addEdit */ public boolean addEdit(UndoableEdit anEdit) { return false; } /** * This default implementation returns false. * * @param anEdit the edit to replace * @return false * * @see UndoableEdit#replaceEdit */ public boolean replaceEdit(UndoableEdit anEdit) { return false; } /** * This default implementation returns true. * * @return true * @see UndoableEdit#isSignificant */ public boolean isSignificant() { return true; } /** * This default implementation returns "". Used by * <code>getUndoPresentationName</code> and * <code>getRedoPresentationName</code> to * construct the strings they return. Subclasses should override to * return an appropriate description of the operation this edit * represents. * * @return the empty string "" * * @see #getUndoPresentationName * @see #getRedoPresentationName */ public String getPresentationName() { return ""; } /** * Retreives the value from the defaults table with key * <code>AbstractUndoableEdit.undoText</code> and returns * that value followed by a space, followed by * <code>getPresentationName</code>. * If <code>getPresentationName</code> returns "", * then the defaults value is returned alone. * * @return the value from the defaults table with key * <code>AbstractUndoableEdit.undoText</code>, followed * by a space, followed by <code>getPresentationName</code> * unless <code>getPresentationName</code> is "" in which * case, the defaults value is returned alone. * @see #getPresentationName */ public String getUndoPresentationName() { String name = getPresentationName(); if (!"".equals(name)) { name = UIManager.getString("AbstractUndoableEdit.undoText") + " " + name; } else { name = UIManager.getString("AbstractUndoableEdit.undoText"); } return name; } /** * Retreives the value from the defaults table with key * <code>AbstractUndoableEdit.redoText</code> and returns * that value followed by a space, followed by * <code>getPresentationName</code>. * If <code>getPresentationName</code> returns "", * then the defaults value is returned alone. * * @return the value from the defaults table with key * <code>AbstractUndoableEdit.redoText</code>, followed * by a space, followed by <code>getPresentationName</code> * unless <code>getPresentationName</code> is "" in which * case, the defaults value is returned alone. * @see #getPresentationName */ public String getRedoPresentationName() { String name = getPresentationName(); if (!"".equals(name)) { name = UIManager.getString("AbstractUndoableEdit.redoText") + " " + name; } else { name = UIManager.getString("AbstractUndoableEdit.redoText"); } return name; } /** * Returns a string that displays and identifies this * object's properties. * * @return a String representation of this object */ public String toString() { return super.toString() + " hasBeenDone: " + hasBeenDone + " alive: " + alive; }}
/*
* Copyright (c) 1997, 2006, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code 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
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package javax.swing.undo;
import java.io.Serializable;
import javax.swing.UIManager;
/**
* An abstract implementation of <code>UndoableEdit</code>,
* implementing simple responses to all boolean methods in
* that interface.
*
* @author Ray Ryan
*/
public class AbstractUndoableEdit implements UndoableEdit, Serializable {
/**
* String returned by <code>getUndoPresentationName</code>;
* as of Java 2 platform v1.3.1 this field is no longer used. This value
* is now localized and comes from the defaults table with key
* <code>AbstractUndoableEdit.undoText</code>.
*
* @see javax.swing.UIDefaults
*/
protected static final String UndoName = "Undo";
/**
* String returned by <code>getRedoPresentationName</code>;
* as of Java 2 platform v1.3.1 this field is no longer used. This value
* is now localized and comes from the defaults table with key
* <code>AbstractUndoableEdit.redoText</code>.
*
* @see javax.swing.UIDefaults
*/
protected static final String RedoName = "Redo";
/**
* Defaults to true; becomes false if this edit is undone, true
* again if it is redone.
*/
boolean hasBeenDone;
/**
* True if this edit has not received <code>die</code>; defaults
* to <code>true</code>.
*/
boolean alive;
/**
* Creates an <code>AbstractUndoableEdit</code> which defaults
* <code>hasBeenDone</code> and <code>alive</code> to <code>true</code>.
*/
public AbstractUndoableEdit() {
super();
hasBeenDone = true;
alive = true;
}
/**
* Sets <code>alive</code> to false. Note that this
* is a one way operation; dead edits cannot be resurrected.
* Sending <code>undo</code> or <code>redo</code> to
* a dead edit results in an exception being thrown.
*
* <p>Typically an edit is killed when it is consolidated by
* another edit's <code>addEdit</code> or <code>replaceEdit</code>
* method, or when it is dequeued from an <code>UndoManager</code>.
*/
public void die() {
alive = false;
}
/**
* Throws <code>CannotUndoException</code> if <code>canUndo</code>
* returns <code>false</code>. Sets <code>hasBeenDone</code>
* to <code>false</code>. Subclasses should override to undo the
* operation represented by this edit. Override should begin with
* a call to super.
*
* @exception CannotUndoException if <code>canUndo</code>
* returns <code>false</code>
* @see #canUndo
*/
public void undo() throws CannotUndoException {
if (!canUndo()) {
throw new CannotUndoException();
}
hasBeenDone = false;
}
/**
* Returns true if this edit is <code>alive</code>
* and <code>hasBeenDone</code> is <code>true</code>.
*
* @return true if this edit is <code>alive</code>
* and <code>hasBeenDone</code> is <code>true</code>
*
* @see #die
* @see #undo
* @see #redo
*/
public boolean canUndo() {
return alive && hasBeenDone;
}
/**
* Throws <code>CannotRedoException</code> if <code>canRedo</code>
* returns false. Sets <code>hasBeenDone</code> to <code>true</code>.
* Subclasses should override to redo the operation represented by
* this edit. Override should begin with a call to super.
*
* @exception CannotRedoException if <code>canRedo</code>
* returns <code>false</code>
* @see #canRedo
*/
public void redo() throws CannotRedoException {
if (!canRedo()) {
throw new CannotRedoException();
}
hasBeenDone = true;
}
/**
* Returns <code>true</code> if this edit is <code>alive</code>
* and <code>hasBeenDone</code> is <code>false</code>.
*
* @return <code>true</code> if this edit is <code>alive</code>
* and <code>hasBeenDone</code> is <code>false</code>
* @see #die
* @see #undo
* @see #redo
*/
public boolean canRedo() {
return alive && !hasBeenDone;
}
/**
* This default implementation returns false.
*
* @param anEdit the edit to be added
* @return false
*
* @see UndoableEdit#addEdit
*/
public boolean addEdit(UndoableEdit anEdit) {
return false;
}
/**
* This default implementation returns false.
*
* @param anEdit the edit to replace
* @return false
*
* @see UndoableEdit#replaceEdit
*/
public boolean replaceEdit(UndoableEdit anEdit) {
return false;
}
/**
* This default implementation returns true.
*
* @return true
* @see UndoableEdit#isSignificant
*/
public boolean isSignificant() {
return true;
}
/**
* This default implementation returns "". Used by
* <code>getUndoPresentationName</code> and
* <code>getRedoPresentationName</code> to
* construct the strings they return. Subclasses should override to
* return an appropriate description of the operation this edit
* represents.
*
* @return the empty string ""
*
* @see #getUndoPresentationName
* @see #getRedoPresentationName
*/
public String getPresentationName() {
return "";
}
/**
* Retreives the value from the defaults table with key
* <code>AbstractUndoableEdit.undoText</code> and returns
* that value followed by a space, followed by
* <code>getPresentationName</code>.
* If <code>getPresentationName</code> returns "",
* then the defaults value is returned alone.
*
* @return the value from the defaults table with key
* <code>AbstractUndoableEdit.undoText</code>, followed
* by a space, followed by <code>getPresentationName</code>
* unless <code>getPresentationName</code> is "" in which
* case, the defaults value is returned alone.
* @see #getPresentationName
*/
public String getUndoPresentationName() {
String name = getPresentationName();
if (!"".equals(name)) {
name = UIManager.getString("AbstractUndoableEdit.undoText") +
" " + name;
} else {
name = UIManager.getString("AbstractUndoableEdit.undoText");
}
return name;
}
/**
* Retreives the value from the defaults table with key
* <code>AbstractUndoableEdit.redoText</code> and returns
* that value followed by a space, followed by
* <code>getPresentationName</code>.
* If <code>getPresentationName</code> returns "",
* then the defaults value is returned alone.
*
* @return the value from the defaults table with key
* <code>AbstractUndoableEdit.redoText</code>, followed
* by a space, followed by <code>getPresentationName</code>
* unless <code>getPresentationName</code> is "" in which
* case, the defaults value is returned alone.
* @see #getPresentationName
*/
public String getRedoPresentationName() {
String name = getPresentationName();
if (!"".equals(name)) {
name = UIManager.getString("AbstractUndoableEdit.redoText") +
" " + name;
} else {
name = UIManager.getString("AbstractUndoableEdit.redoText");
}
return name;
}
/**
* Returns a string that displays and identifies this
* object's properties.
*
* @return a String representation of this object
*/
public String toString()
{
return super.toString()
+ " hasBeenDone: " + hasBeenDone
+ " alive: " + alive;
}
}