boolean addEdit(UndoableEdit anEdit)
boolean canRedo()
boolean canUndo()
void die()
String getPresentationName()
String getRedoPresentationName()
String getUndoPresentationName()
boolean isSignificant()
void redo() throws CannotRedoException
boolean replaceEdit(UndoableEdit anEdit)
void undo() throws CannotUndoException