javax.swing.undo
Class AbstractUndoableEdit

java.lang.Object
  |
  +--javax.swing.undo.AbstractUndoableEdit

Direct Known Subclasses:

AbstractDocument.ElementEdit, CompoundEdit, DefaultStyledDocument.AttributeUndoableEdit, StateEdit

public class AbstractUndoableEdit

extends Object

implements UndoableEdit, Serializable

An abstract implementation of UndoableEdit, implementing simple responses to all boolean methods in that interface.

See Also:

Serialized Form

Field Summary

protected static String	RedoName String returned by getRedoPresentationName()
protected static String	UndoName String returned by getUndoPresentationName()

Constructor Summary

AbstractUndoableEdit()

Method Summary

boolean	addEdit(UndoableEdit anEdit) This default implementation returns false.
boolean	canRedo() Returns true if this edit is alive and hasBeenDone is false.
boolean	canUndo() Returns true if this edit is alive and hasBeenDone is true.
void	die() Sets alive to false.
String	getPresentationName() This default implementation returns "".
String	getRedoPresentationName() If getPresentationName() returns "", returns AbstractUndoableEdit.RedoName.
String	getUndoPresentationName() If getPresentationName() returns "", returns AbstractUndoableEdit.UndoName.
boolean	isSignificant() This default implementation returns true.
void	redo() Throws CannotRedoException if canRedo() returns false.
boolean	replaceEdit(UndoableEdit anEdit) This default implementation returns false.
String	toString() Returns a string that displays and identifies this object's properties.
void	undo() Throws CannotUndoException if canUndo() returns false.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

UndoName

protected static final String UndoName

String returned by getUndoPresentationName()

RedoName

protected static final String RedoName

String returned by getRedoPresentationName()

Constructor Detail

AbstractUndoableEdit

public AbstractUndoableEdit()

Method Detail

die

public void die()

Sets alive to false. Note that this is a one way operation: dead edits cannot be resurrected. Sending undo() or redo() to a dead edit results in an exception being thrown. Typically an edit is killed when it is consolidated by another edit's addEdit() or replaceEdit() method, or when it is dequeued from an UndoManager

Specified by:

die in interface UndoableEdit

undo

public void undo()
          throws CannotUndoException

Throws CannotUndoException if canUndo() returns false. Sets hasBeenDone to false. Subclasses should override to undo the operation represented by this edit. Override should begin with a call to super.

Specified by:

undo in interface UndoableEdit

See Also:

canUndo()

canUndo

public boolean canUndo()

Returns true if this edit is alive and hasBeenDone is true.

Specified by:

canUndo in interface UndoableEdit

See Also:

die(), undo(), redo()

redo

public void redo()
          throws CannotRedoException

Throws CannotRedoException if canRedo() returns false. Sets hasBeenDone to true. Subclasses should override to redo the operation represented by this edit. Override should begin with a call to super.

Specified by:

redo in interface UndoableEdit

See Also:

canRedo()

canRedo

public boolean canRedo()

Returns true if this edit is alive and hasBeenDone is false.

Specified by:

canRedo in interface UndoableEdit

See Also:

die(), undo(), redo()

addEdit

public boolean addEdit(UndoableEdit anEdit)

This default implementation returns false.

Specified by:

addEdit in interface UndoableEdit

See Also:

UndoableEdit.addEdit(javax.swing.undo.UndoableEdit)

replaceEdit

public boolean replaceEdit(UndoableEdit anEdit)

This default implementation returns false.

Specified by:

replaceEdit in interface UndoableEdit

See Also:

UndoableEdit.replaceEdit(javax.swing.undo.UndoableEdit)

isSignificant

public boolean isSignificant()

This default implementation returns true.

Specified by:

isSignificant in interface UndoableEdit

See Also:

UndoableEdit.isSignificant()

getPresentationName

public String getPresentationName()

This default implementation returns "". Used by getUndoPresentationName() and getRedoPresentationName() to construct the strings they return. Subclasses shoul override to return an appropriate description of the operation this edit represents.

Specified by:

getPresentationName in interface UndoableEdit

See Also:

getUndoPresentationName(), getRedoPresentationName()

getUndoPresentationName

public String getUndoPresentationName()

If getPresentationName() returns "", returns AbstractUndoableEdit.UndoName. Otherwise returns AbstractUndoableEdit.UndoName followed by a space and getPresentationName()

Specified by:

getUndoPresentationName in interface UndoableEdit

See Also:

getPresentationName()

getRedoPresentationName

public String getRedoPresentationName()

If getPresentationName() returns "", returns AbstractUndoableEdit.RedoName. Otherwise returns AbstractUndoableEdit.RedoName followed by a space and getPresentationName()

Specified by:

getRedoPresentationName in interface UndoableEdit

See Also:

getPresentationName()

toString

public String toString()

Returns a string that displays and identifies this object's properties.

Returns:

a String representation of this object

Overrides:

toString in class Object