Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||
ChildrenDrivenMutableTree |
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| 1.9090909090909092;1.909 |
1 | /* | |
2 | * $Source$ | |
3 | * $Revision$ | |
4 | * | |
5 | * Copyright (C) 2001 Myles Chippendale | |
6 | * | |
7 | * Part of Melati (http://melati.org), a framework for the rapid | |
8 | * development of clean, maintainable web applications. | |
9 | * | |
10 | * Melati is free software; Permission is granted to copy, distribute | |
11 | * and/or modify this software under the terms either: | |
12 | * | |
13 | * a) the GNU General Public License as published by the Free Software | |
14 | * Foundation; either version 2 of the License, or (at your option) | |
15 | * any later version, | |
16 | * | |
17 | * or | |
18 | * | |
19 | * b) any version of the Melati Software License, as published | |
20 | * at http://melati.org | |
21 | * | |
22 | * You should have received a copy of the GNU General Public License and | |
23 | * the Melati Software License along with this program; | |
24 | * if not, write to the Free Software Foundation, Inc., | |
25 | * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA to obtain the | |
26 | * GNU General Public License and visit http://melati.org to obtain the | |
27 | * Melati Software License. | |
28 | * | |
29 | * Feel free to contact the Developers of Melati (http://melati.org), | |
30 | * if you would like to work out a different arrangement than the options | |
31 | * outlined here. It is our intention to allow Melati to be used by as | |
32 | * wide an audience as possible. | |
33 | * | |
34 | * This program is distributed in the hope that it will be useful, | |
35 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
36 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
37 | * GNU General Public License for more details. | |
38 | * | |
39 | * Contact details for copyright holder: | |
40 | * | |
41 | * Myles Chippendale <mylesc At paneris.org> | |
42 | */ | |
43 | package org.melati.util; | |
44 | ||
45 | import javax.swing.tree.DefaultMutableTreeNode; | |
46 | import java.util.Vector; | |
47 | import java.util.Enumeration; | |
48 | import org.melati.poem.Treeable; | |
49 | ||
50 | /** | |
51 | * A tree of <code>DefaultMutableTreeNode</code>s, | |
52 | * the <code>userObject</code>s of which | |
53 | * are {@link Treeable} objects which supply their own | |
54 | * <code>getChildren()</code> functions. | |
55 | * This is used to build the tree of | |
56 | * <code>DefaultMutableTreeNode</code>s. | |
57 | * <p> | |
58 | * It also allows you to search the subtree for a particular | |
59 | * {@link Treeable} object and returns the corresponding | |
60 | * <code>DefaultMutableTreeNode</code> object if one exists. | |
61 | * | |
62 | * @see DefaultMutableTreeNode | |
63 | * | |
64 | * @since 04/10/2000 | |
65 | * @author Myles Chippendale | |
66 | **/ | |
67 | ||
68 | ||
69 | public class ChildrenDrivenMutableTree { | |
70 | ||
71 | /** | |
72 | * An enumeration that is always empty. This is used when an enumeration | |
73 | * of a leaf node's children is requested. | |
74 | */ | |
75 | // FIXME we need our own empty enumeration | |
76 | @SuppressWarnings("rawtypes") | |
77 | 0 | public static final Enumeration EMPTY_ENUMERATION = |
78 | DefaultMutableTreeNode.EMPTY_ENUMERATION; | |
79 | ||
80 | /** root node */ | |
81 | protected DefaultMutableTreeNode root; | |
82 | ||
83 | /** | |
84 | * Constructor. | |
85 | */ | |
86 | public ChildrenDrivenMutableTree() { | |
87 | 0 | this(null); |
88 | 0 | } |
89 | ||
90 | /** | |
91 | * Constructor. | |
92 | * @param userObject the root | |
93 | */ | |
94 | 0 | public ChildrenDrivenMutableTree(Treeable userObject) { |
95 | 0 | root = new DefaultMutableTreeNode(userObject); |
96 | 0 | buildTree(); |
97 | 0 | } |
98 | ||
99 | /** | |
100 | * Compute the children. | |
101 | */ | |
102 | public void buildTree() { | |
103 | 0 | buildTree(computeChildren(root)); |
104 | 0 | } |
105 | ||
106 | /** | |
107 | * Compute the children given the nodes. | |
108 | * @param nodes an Enumeration of nodes | |
109 | */ | |
110 | public void buildTree(Enumeration<DefaultMutableTreeNode> nodes) { | |
111 | 0 | while (nodes.hasMoreElements()) |
112 | 0 | buildTree(computeChildren(nodes.nextElement())); |
113 | 0 | } |
114 | ||
115 | @SuppressWarnings("unchecked") | |
116 | private static Enumeration<DefaultMutableTreeNode> computeChildren(DefaultMutableTreeNode node) { | |
117 | 0 | if (node == null) |
118 | 0 | return EMPTY_ENUMERATION; |
119 | 0 | Treeable[] kids = ((Treeable)node.getUserObject()).getChildren(); |
120 | 0 | for(int i = 0; i<kids.length; i++) { |
121 | 0 | node.add(new DefaultMutableTreeNode(kids[i])); |
122 | } | |
123 | 0 | return node.children(); |
124 | } | |
125 | ||
126 | ||
127 | /** | |
128 | * Find a node in a tree. | |
129 | * @param search the node object | |
130 | * @return a tree node | |
131 | */ | |
132 | @SuppressWarnings("unchecked") | |
133 | public DefaultMutableTreeNode getTreeNodeFor(Treeable search) { | |
134 | ||
135 | 0 | Vector<DefaultMutableTreeNode> agenda = new Vector<DefaultMutableTreeNode>(); |
136 | 0 | agenda.addElement(root); |
137 | ||
138 | 0 | while (!agenda.isEmpty()) { |
139 | 0 | DefaultMutableTreeNode current = |
140 | 0 | agenda.firstElement(); |
141 | 0 | if (current == null) |
142 | 0 | return null; |
143 | 0 | if (current.getUserObject() == search) |
144 | 0 | return current; |
145 | ||
146 | 0 | agenda.removeElementAt(0); |
147 | 0 | Enumeration<DefaultMutableTreeNode> kids = current.children(); |
148 | 0 | while(kids.hasMoreElements()) { |
149 | 0 | agenda.addElement(kids.nextElement()); |
150 | } | |
151 | 0 | } |
152 | 0 | return null; |
153 | } | |
154 | ||
155 | /** | |
156 | * @return the root | |
157 | */ | |
158 | public DefaultMutableTreeNode getRoot() { | |
159 | 0 | return root; |
160 | } | |
161 | ||
162 | /** | |
163 | * Return an enumeration of nodes in preorder, whatever | |
164 | * that means. | |
165 | * <p> | |
166 | * Root is first node. What is the difference | |
167 | * from breadth first? | |
168 | * @return the nodes | |
169 | */ | |
170 | @SuppressWarnings("unchecked") | |
171 | public Enumeration<TreeNode> preorderEnumeration() { | |
172 | 0 | return root.preorderEnumeration(); |
173 | } | |
174 | ||
175 | /** | |
176 | * Return an enumeration of nodes in postorder, whatever | |
177 | * that means. | |
178 | * <p> | |
179 | * Leftmost leaf is first. What is the difference | |
180 | * from depth first? | |
181 | * @return the nodes | |
182 | */ | |
183 | @SuppressWarnings("unchecked") | |
184 | public Enumeration<TreeNode> postorderEnumeration() { | |
185 | 0 | return root.postorderEnumeration(); |
186 | } | |
187 | ||
188 | /** | |
189 | * @return an enumeration of nodes in breadth first order. | |
190 | */ | |
191 | @SuppressWarnings("unchecked") | |
192 | public Enumeration<TreeNode> breadthFirstEnumeration() { | |
193 | 0 | return root.breadthFirstEnumeration(); |
194 | } | |
195 | ||
196 | /** | |
197 | * @return an enumeration of nodes in depth first order. | |
198 | */ | |
199 | @SuppressWarnings("unchecked") | |
200 | public Enumeration<TreeNode> depthFirstEnumeration() { | |
201 | 0 | return root.depthFirstEnumeration(); |
202 | } | |
203 | } |