StateEdit

java.lang.Object
- javax.swing.undo.AbstractUndoableEdit
- - javax.swing.undo.StateEdit

All Implemented Interfaces:

Serializable, UndoableEdit
```
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.
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!
See Also:

StateEditable

Field Summary

Fields

Modifier and Type	Field and Description
`protected StateEditable`	`object` The object being edited
`protected Hashtable<Object,Object>`	`postState` The state information after the edit
`protected Hashtable<Object,Object>`	`preState` The state information prior to the edit
`protected static String`	`RCSID`
`protected String`	`undoRedoName` The undo/redo presentation name

Fields inherited from class javax.swing.undo.AbstractUndoableEdit
RedoName, UndoName

Constructor Summary

Constructors

Constructor and Description
`StateEdit(StateEditable anObject)` Create and return a new StateEdit.
`StateEdit(StateEditable anObject, String name)` Create and return a new StateEdit with a presentation name.

Method Summary

All Methods

Instance Methods

Concrete Methods
Modifier and Type	Method and Description
`void`	`end()` Gets the post-edit state of the StateEditable object and ends the edit.
`String`	`getPresentationName()` Gets the presentation name for this edit
`protected void`	`init(StateEditable anObject, String name)`
`void`	`redo()` Tells the edited object to apply the state after the edit
`protected void`	`removeRedundantState()` Remove redundant key/values in state hashtables.
`void`	`undo()` Tells the edited object to apply the state prior to the edit

Methods inherited from class javax.swing.undo.AbstractUndoableEdit
addEdit, canRedo, canUndo, die, getRedoPresentationName, getUndoPresentationName, isSignificant, replaceEdit, toString

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Field Detail
  - RCSID
```
protected static final String RCSID
```
    See Also:
    
    Constant Field Values
  - object
```
protected StateEditable object
```
    The object being edited
  - preState
```
protected Hashtable<Object,Object> preState
```
    The state information prior to the edit
  - postState
```
protected Hashtable<Object,Object> postState
```
    The state information after the edit
  - undoRedoName
```
protected String undoRedoName
```
    The undo/redo presentation name
- Constructor Detail
  - StateEdit
```
public StateEdit(StateEditable anObject)
```
    Create and return a new StateEdit.
    
    Parameters:
    
    anObject - The object to watch for changing state
    
    See Also:
    
    StateEdit
  - 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
- Method Detail
  - init
```
protected void init(StateEditable anObject,
                    String name)
```
  - end
```
public void end()
```
    Gets the post-edit state of the StateEditable object and ends the edit.
  - undo
```
public void undo()
```
    Tells the edited object to apply the state prior to the edit
    
    Specified by:
    
    undo in interface UndoableEdit
    
    Overrides:
    
    undo in class AbstractUndoableEdit
    
    See Also:
    
    AbstractUndoableEdit.canUndo()
  - redo
```
public void redo()
```
    Tells the edited object to apply the state after the edit
    
    Specified by:
    
    redo in interface UndoableEdit
    
    Overrides:
    
    redo in class AbstractUndoableEdit
    
    See Also:
    
    AbstractUndoableEdit.canRedo()
  - getPresentationName
```
public String getPresentationName()
```
    Gets the presentation name for this edit
    
    Specified by:
    
    getPresentationName in interface UndoableEdit
    
    Overrides:
    
    getPresentationName in class AbstractUndoableEdit
    
    Returns:
    
    the empty string ""
    
    See Also:
    
    AbstractUndoableEdit.getUndoPresentationName(), AbstractUndoableEdit.getRedoPresentationName()
  - removeRedundantState
```
protected void removeRedundantState()
```
    Remove redundant key/values in state hashtables.

Class StateEdit

Field Summary

Fields

Fields inherited from class javax.swing.undo.AbstractUndoableEdit

Constructor Summary

Constructors

Method Summary

Methods inherited from class javax.swing.undo.AbstractUndoableEdit

Methods inherited from class java.lang.Object

Field Detail

RCSID

object

preState

postState

undoRedoName

Constructor Detail

StateEdit

StateEdit

Method Detail

init

end

undo

redo

getPresentationName

removeRedundantState