All Packages  Class Hierarchy  This Package  Previous  Next  Index

Class com.sun.java.swing.undo.StateEdit

java.lang.Object
   |
   +----com.sun.java.swing.undo.AbstractUndoableEdit
           |
           +----com.sun.java.swing.undo.StateEdit

public class StateEdit

extends AbstractUndoableEdit

StateEdit is a general edit for objects that change state. Objects being edited must conform to the StateEditable interface.

This edit class works by asking an object to store it's state in Hashtables before and after editing occurs. Upon undo or redo the object is told to restore it's state from these Hashtables.

	// Create the edit during the "before" state of the object
	StateEdit newEdit = new StateEdit(myObject);
	// Modify the object
	myObject.someStateModifyingMethod();
	// "end" the edit when you are done modifying the object
	newEdit.end();
 

Note that when a StateEdit ends, it removes redundant state from the Hashtables - A state Hashtable is not guaranteed to contain all keys/values placed into it when the state is stored!

See Also:

StateEditable

object

The object being edited

postState

The state information after the edit

preState

The state information prior to the edit

RCSID

undoRedoName

The undo/redo presentation name

StateEdit(StateEditable)

Create and return a new StateEdit.

StateEdit(StateEditable, String)

Create and return a new StateEdit with a presentation name.

end()

Gets the post-edit state of the StateEditable object and ends the edit.

getPresentationName()

Gets the presentation name for this edit

init(StateEditable, String)

redo()

Tells the edited object to apply the state after the edit

removeRedundantState()

Remove redundant key/values in state hashtables.

undo()

Tells the edited object to apply the state prior to the edit

 protected static final String RCSID

 protected StateEditable object

The object being edited

 protected Hashtable preState

The state information prior to the edit

 protected Hashtable postState

The state information after the edit

 protected String undoRedoName

The undo/redo presentation name

 public StateEdit(StateEditable anObject)

Create and return a new StateEdit.

Parameters:

anObject - The object to watch for changing state

See Also:

StateEdit

 public StateEdit(StateEditable anObject,
                  String name)

Create and return a new StateEdit with a presentation name.

Parameters:

anObject - The object to watch for changing state

name - The presentation name to be used for this edit

See Also:

StateEdit

 protected void init(StateEditable anObject,
                     String name)

 public void end()

Gets the post-edit state of the StateEditable object and ends the edit.

 public void undo()

Tells the edited object to apply the state prior to the edit

Overrides:

undo in class AbstractUndoableEdit

 public void redo()

Tells the edited object to apply the state after the edit

Overrides:

redo in class AbstractUndoableEdit

 public String getPresentationName()

Gets the presentation name for this edit

Overrides:

getPresentationName in class AbstractUndoableEdit

 protected void removeRedundantState()

Remove redundant key/values in state hashtables.

All Packages  Class Hierarchy  This Package  Previous  Next  Index