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javax.swing.undo
public class: StateEdit [javadoc | source]
java.lang.Object
   javax.swing.undo.AbstractUndoableEdit
      javax.swing.undo.StateEdit

All Implemented Interfaces:
    UndoableEdit, Serializable

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.

A state edit is used as follows:
     // 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!

Field Summary
protected static final  String RCSID     
protected  StateEditable object    The object being edited 
protected  Hashtable<Object, Object> preState    The state information prior to the edit 
protected  Hashtable<Object, Object> postState    The state information after the edit 
protected  String undoRedoName    The undo/redo presentation name 
Fields inherited from javax.swing.undo.AbstractUndoableEdit:
UndoName,  RedoName,  hasBeenDone,  alive
Constructor:
 public StateEdit(StateEditable anObject) 
    Create and return a new StateEdit.
    Parameters:
    anObject - The object to watch for changing state
    Also see:
    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
    Also see:
    StateEdit
Method from javax.swing.undo.StateEdit Summary:
end,   getPresentationName,   init,   redo,   removeRedundantState,   undo
Methods from javax.swing.undo.AbstractUndoableEdit:
addEdit,   canRedo,   canUndo,   die,   getPresentationName,   getRedoPresentationName,   getUndoPresentationName,   isSignificant,   redo,   replaceEdit,   toString,   undo
Methods from java.lang.Object:
clone,   equals,   finalize,   getClass,   hashCode,   notify,   notifyAll,   toString,   wait,   wait,   wait
Method from javax.swing.undo.StateEdit Detail:
 public  void end() 
    Gets the post-edit state of the StateEditable object and ends the edit.
 public String getPresentationName() 
    Gets the presentation name for this edit
 protected  void init(StateEditable anObject,
    String name) 
 public  void redo() 
    Tells the edited object to apply the state after the edit
 protected  void removeRedundantState() 
    Remove redundant key/values in state hashtables.
 public  void undo() 
    Tells the edited object to apply the state prior to the edit