Java tutorial
/* * Copyright (c) 1997, 2014, 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 * or visit www.oracle.com if you need additional information or have any * questions. */ package javax.swing.tree; import java.util.Enumeration; /** * Defines the requirements for an object that can be used as a * tree node in a JTree. * <p> * Implementations of <code>TreeNode</code> that override <code>equals</code> * will typically need to override <code>hashCode</code> as well. Refer * to {@link javax.swing.tree.TreeModel} for more information. * * For further information and examples of using tree nodes, * see <a href="https://docs.oracle.com/javase/tutorial/uiswing/components/tree.html">How to Use Tree Nodes</a> * in <em>The Java Tutorial.</em> * * @author Rob Davis * @author Scott Violet */ public interface TreeNode { /** * Returns the child <code>TreeNode</code> at index * <code>childIndex</code>. * * @param childIndex index of child * @return the child node at given index */ TreeNode getChildAt(int childIndex); /** * Returns the number of children <code>TreeNode</code>s the receiver * contains. * * @return the number of children the receiver contains */ int getChildCount(); /** * Returns the parent <code>TreeNode</code> of the receiver. * * @return the parent of the receiver */ TreeNode getParent(); /** * Returns the index of <code>node</code> in the receivers children. * If the receiver does not contain <code>node</code>, -1 will be * returned. * * @param node node to be loked for * @return index of specified node */ int getIndex(TreeNode node); /** * Returns true if the receiver allows children. * * @return whether the receiver allows children */ boolean getAllowsChildren(); /** * Returns true if the receiver is a leaf. * * @return whether the receiver is a leaf */ boolean isLeaf(); /** * Returns the children of the receiver as an <code>Enumeration</code>. * * @return the children of the receiver as an {@code Enumeration} */ Enumeration<? extends TreeNode> children(); }