001/* TreeNode.java -- 002 Copyright (C) 2002, 2006, Free Software Foundation, Inc. 003 004This file is part of GNU Classpath. 005 006GNU Classpath is free software; you can redistribute it and/or modify 007it under the terms of the GNU General Public License as published by 008the Free Software Foundation; either version 2, or (at your option) 009any later version. 010 011GNU Classpath is distributed in the hope that it will be useful, but 012WITHOUT ANY WARRANTY; without even the implied warranty of 013MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 014General Public License for more details. 015 016You should have received a copy of the GNU General Public License 017along with GNU Classpath; see the file COPYING. If not, write to the 018Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 01902110-1301 USA. 020 021Linking this library statically or dynamically with other modules is 022making a combined work based on this library. Thus, the terms and 023conditions of the GNU General Public License cover the whole 024combination. 025 026As a special exception, the copyright holders of this library give you 027permission to link this library with independent modules to produce an 028executable, regardless of the license terms of these independent 029modules, and to copy and distribute the resulting executable under 030terms of your choice, provided that you also meet, for each linked 031independent module, the terms and conditions of the license of that 032module. An independent module is a module which is not derived from 033or based on this library. If you modify this library, you may extend 034this exception to your version of the library, but you are not 035obligated to do so. If you do not wish to do so, delete this 036exception statement from your version. */ 037 038 039package javax.swing.tree; 040 041import java.util.Enumeration; 042 043/** 044 * A tree node. 045 * 046 * @author Andrew Selkirk 047 */ 048public interface TreeNode 049{ 050 051 /** 052 * Returns the parent node for this tree node, or <code>null</code> if this 053 * node has no parent. 054 * 055 * @return The parent node (possibly <code>null</code>). 056 */ 057 TreeNode getParent(); 058 059 /** 060 * Returns the index of the specified child node, or -1 if the node is not 061 * in fact a child of this node. 062 * 063 * @param node the node (<code>null</code> not permitted). 064 * 065 * @return The index of the specified child node, or -1. 066 * 067 * @throws IllegalArgumentException if <code>node</code> is <code>null</code>. 068 */ 069 int getIndex(TreeNode node); 070 071 /** 072 * Returns the child node at the given index. 073 * 074 * @param index the index (in the range <code>0</code> to 075 * <code>getChildCount() - 1</code>). 076 * 077 * @return The child node at the given index. 078 */ 079 TreeNode getChildAt(int index); 080 081 /** 082 * Returns the number of children for this node. 083 * 084 * @return The number of children for this node. 085 */ 086 int getChildCount(); 087 088 /** 089 * Returns <code>true</code> if this node allows children, and 090 * <code>false</code> otherwise. 091 * 092 * @return A boolean. 093 */ 094 boolean getAllowsChildren(); 095 096 /** 097 * Returns <code>true</code> if this node is a leaf node, and 098 * <code>false</code> otherwise. 099 * 100 * @return A boolean. 101 */ 102 boolean isLeaf(); 103 104 /** 105 * Returns an enumeration of the children of this node, or an empty 106 * enumeration if this node has no children. 107 * 108 * @return An enumeration of the children of this node. 109 */ 110 @SuppressWarnings("unchecked") // Required for API compatibility 111 Enumeration children(); 112 113}