Class 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
, Serialized Form
Field Summary
Modifier and Type | Field | 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 | Obsolete RCS version identity. |
protected String | undoRedoName | The undo/redo presentation name |
Fields declared in class javax.swing.undo.AbstractUndoableEdit
RedoName, UndoName
Constructor Summary
Constructor | 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
Modifier and Type | Method | 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) | Initialize the state edit. |
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 declared in class javax.swing.undo.AbstractUndoableEdit
addEdit, canRedo, canUndo, die, getRedoPresentationName, getUndoPresentationName, isSignificant, replaceEdit, toString
Methods declared in class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
Field Detail
RCSID
protected static final String RCSID
Obsolete RCS version identity.
- 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)
Initialize the state edit.
- Parameters:
-
anObject
- The object to watch for changing state -
name
- The presentation name to be used for this edit
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 interfaceUndoableEdit
- Overrides:
-
undo
in classAbstractUndoableEdit
- See Also:
AbstractUndoableEdit.canUndo()
redo
public void redo()
Tells the edited object to apply the state after the edit
- Specified by:
-
redo
in interfaceUndoableEdit
- Overrides:
-
redo
in classAbstractUndoableEdit
- See Also:
AbstractUndoableEdit.canRedo()
getPresentationName
public String getPresentationName()
Gets the presentation name for this edit
- Specified by:
-
getPresentationName
in interfaceUndoableEdit
- Overrides:
-
getPresentationName
in classAbstractUndoableEdit
- Returns:
- the empty string ""
- See Also:
-
AbstractUndoableEdit.getUndoPresentationName()
,AbstractUndoableEdit.getRedoPresentationName()
removeRedundantState
protected void removeRedundantState()
Remove redundant key/values in state hashtables.