1. /*

  2.  * @(#)TreeWillExpandListener.java	1.4 01/11/29

  3.  *

  4.  * Copyright 2002 Sun Microsystems, Inc. All rights reserved.

  5.  * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.

  6.  */

  7. 

  8. package javax.swing.event;

  9. 

  10. import java.util.EventListener;

  11. import javax.swing.tree.ExpandVetoException;

  12. 

  13. /**

  14.   * The listener that's notified when a tree expands or collapses

  15.   * a node.

  16.   *

  17.   * @version 1.4 11/29/01

  18.   * @author Scott Violet

  19.   */

  20. 

  21. public interface TreeWillExpandListener extends EventListener {

  22.     /**

  23.      * Invoked whenever a node in the tree is about to be expanded.

  24.      */

  25.     public void treeWillExpand(TreeExpansionEvent event) throws ExpandVetoException;

  26. 

  27.     /**

  28.      * Invoked whenever a node in the tree is about to be collapsed.

  29.      */

  30.     public void treeWillCollapse(TreeExpansionEvent event) throws ExpandVetoException;

  31. }