/*
 * Copyright (c) 1998, 1999, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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 */

package javax.swing.event;

import java.util.EventListener;
import javax.swing.tree.ExpandVetoException;

/**
  * The listener that's notified when a tree expands or collapses
  * a node.
  * For further information and examples see
  * <a href="http://docs.oracle.com/javase/tutorial/uiswing/events/treewillexpandlistener.html">How to Write a Tree-Will-Expand Listener</a>,
  * a section in <em>The Java Tutorial.</em>
  *
  * @author Scott Violet
  */

public interface TreeWillExpandListener extends EventListener {
    /**
     * Invoked whenever a node in the tree is about to be expanded.
     */
    public void treeWillExpand(TreeExpansionEvent event) throws ExpandVetoException;

    /**
     * Invoked whenever a node in the tree is about to be collapsed.
     */
    public void treeWillCollapse(TreeExpansionEvent event) throws ExpandVetoException;
}