File	Doc	Category	Size	Date	Package
UndoableEditSupport.java	API Doc	Java SE 5 API	4425	Fri Aug 26 14:58:22 BST 2005	javax.swing.undo

UndoableEditSupport

• java.lang.Object

Fields Summary
protected int	updateLevel
protected CompoundEdit	compoundEdit
protected Vector	listeners
protected Object	realSource

Constructors Summary
public UndoableEditSupport() Constructs an UndoableEditSupport object. this(null);
public UndoableEditSupport(Object r) Constructs an UndoableEditSupport object. param r an Object realSource = r == null ? this : r; updateLevel = 0; compoundEdit = null; listeners = new Vector<UndoableEditListener>();

Methods Summary
protected void	_postEdit(javax.swing.undo.UndoableEdit e) Called only from postEdit and endUpdate. Calls undoableEditHappened in all listeners. No synchronization is performed here, since the two calling methods are synchronized. UndoableEditEvent ev = new UndoableEditEvent(realSource, e); Enumeration cursor = ((Vector)listeners.clone()).elements(); while (cursor.hasMoreElements()) { ((UndoableEditListener)cursor.nextElement()). undoableEditHappened(ev); }
public synchronized void	addUndoableEditListener(javax.swing.event.UndoableEditListener l) Registers an UndoableEditListener. The listener is notified whenever an edit occurs which can be undone. param l an UndoableEditListener object see #removeUndoableEditListener listeners.addElement(l);
public synchronized void	beginUpdate() if (updateLevel == 0) { compoundEdit = createCompoundEdit(); } updateLevel++;
protected javax.swing.undo.CompoundEdit	createCompoundEdit() Called only from beginUpdate. Exposed here for subclasses' use. return new CompoundEdit();
public synchronized void	endUpdate() DEADLOCK WARNING: Calling this method may call undoableEditHappened in all listeners. It is unwise to call this method from one of its listeners. updateLevel--; if (updateLevel == 0) { compoundEdit.end(); _postEdit(compoundEdit); compoundEdit = null; }
public synchronized javax.swing.event.UndoableEditListener[]	getUndoableEditListeners() Returns an array of all the UndoableEditListeners added to this UndoableEditSupport with addUndoableEditListener(). return all of the UndoableEditListeners added or an empty array if no listeners have been added since 1.4 return (UndoableEditListener[])(listeners.toArray( new UndoableEditListener[0]));
public int	getUpdateLevel() Returns the update level value. return an integer representing the update level return updateLevel;
public synchronized void	postEdit(javax.swing.undo.UndoableEdit e) DEADLOCK WARNING: Calling this method may call undoableEditHappened in all listeners. It is unwise to call this method from one of its listeners. if (updateLevel == 0) { _postEdit(e); } else { // PENDING(rjrjr) Throw an exception if this fails? compoundEdit.addEdit(e); }
public synchronized void	removeUndoableEditListener(javax.swing.event.UndoableEditListener l) Removes an UndoableEditListener. param l the UndoableEditListener object to be removed see #addUndoableEditListener listeners.removeElement(l);
public java.lang.String	toString() Returns a string that displays and identifies this object's properties. return a String representation of this object return super.toString() + " updateLevel: " + updateLevel + " listeners: " + listeners + " compoundEdit: " + compoundEdit;