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Interface com.sun.java.swing.undo.UndoableEdit

public interface UndoableEdit

addEdit(UndoableEdit)

This UndoableEdit should absorb anEdit if it can.

canRedo()

True if it is still possible to redo this operation

canUndo()

True if it is still possible to undo this operation

die()

May be sent to inform an edit that it should no longer be used.

getPresentationName()

Provide a localized, human readable description of this edit suitable for use in, say, a change log.

getRedoPresentationName()

Provide a localized, human readable description of the redoable form of this edit, e.g.

getUndoPresentationName()

Provide a localized, human readable description of the undoable form of this edit, e.g.

isSignificant()

Return false if this edit is insignificant--for example one that maintains the user's selection, but does not change any model state.

redo()

Re-apply the edit, assuming that it has been undone.

replaceEdit(UndoableEdit)

Return true if this UndoableEdit should replace anEdit.

undo()

Undo the edit that was made.

 public abstract void undo() throws CannotUndoException

Undo the edit that was made.

 public abstract boolean canUndo()

True if it is still possible to undo this operation

 public abstract void redo() throws CannotRedoException

Re-apply the edit, assuming that it has been undone.

 public abstract boolean canRedo()

True if it is still possible to redo this operation

 public abstract void die()

May be sent to inform an edit that it should no longer be used. This is a useful hook for cleaning up state no longer needed once undoing or redoing is impossible--for example, deleting file resources used by objects that can no longer be undeleted. UndoManager calls this before it dequeues edits. Note that this is a one-way operation. There is no "undie" method.

See Also:

die

 public abstract boolean addEdit(UndoableEdit anEdit)

This UndoableEdit should absorb anEdit if it can. Return true if anEdit has been incoporated, false if it has not.

Typically the receiver is already in the queue of a UndoManager (or other UndoableEditListener), and is being given a chance to incorporate anEdit rather than letting it be added to the queue in turn.

If true is returned, from now on anEdit must return false from canUndo() and canRedo(), and must throw the appropriate exception on undo() or redo().

 public abstract boolean replaceEdit(UndoableEdit anEdit)

Return true if this UndoableEdit should replace anEdit. The receiver should incorporate anEdit's state before returning true.

This message is the opposite of addEdit--anEdit has typically already been queued in a UndoManager (or other UndoableEditListener), and the receiver is being given a chance to take its place.

If true is returned, from now on anEdit must return false from canUndo() and canRedo(), and must throw the appropriate exception on undo() or redo().

 public abstract boolean isSignificant()

Return false if this edit is insignificant--for example one that maintains the user's selection, but does not change any model state. This status can be used by an UndoableEditListener (like UndoManager) when deciding which UndoableEdits to present to the user as Undo/Redo options, and which to perform as side effects of undoing or redoing other events.

 public abstract String getPresentationName()

Provide a localized, human readable description of this edit suitable for use in, say, a change log.

 public abstract String getUndoPresentationName()

Provide a localized, human readable description of the undoable form of this edit, e.g. for use as an Undo menu item. Typically derived from getDescription();

 public abstract String getRedoPresentationName()

Provide a localized, human readable description of the redoable form of this edit, e.g. for use as a Redo menu item. Typically derived from getPresentationName();

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