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18
19 package swingwtx.swing.tree;
20
21 import java.util.ArrayList  ;
22 import java.util.Enumeration ;
23 import java.util.NoSuchElementException ;
24 import java.util.Vector ;
25
26 public class DefaultMutableTreeNode implements MutableTreeNode {
27
28
29 public org.eclipse.swt.widgets.TreeItem peer = null;
30
31
32 static public final Enumeration EMPTY_ENUMERATION = new Enumeration () {
33 public Object nextElement() {
34 throw new NoSuchElementException ("No elements");
35 }
36 public boolean hasMoreElements() { return false; }
37 };
38
39 protected MutableTreeNode parent;
40 protected boolean allowsChildren;
41 protected Vector children;
42 protected Object userObject;
43
44 public DefaultMutableTreeNode() {
45 this(null);
46 }
47
48 public DefaultMutableTreeNode(Object userObject) {
49 this(userObject, true);
50 }
51
52 public DefaultMutableTreeNode(Object userObject, boolean allowsChildren) {
53 super();
54 this.allowsChildren = allowsChildren;
55 this.userObject = userObject;
56 parent = null;
57 }
58
59 public void insert(MutableTreeNode newChild, int childIndex) {
60 MutableTreeNode oldParent = (MutableTreeNode) newChild.getParent();
61 if (oldParent != null)
62 oldParent.remove(newChild);
63 newChild.setParent(this);
64 if (children == null)
65 children = new Vector ();
66 children.insertElementAt(newChild, childIndex);
67 }
68
69 public void remove(int childIndex) {
70 MutableTreeNode child = (MutableTreeNode) getChildAt(childIndex);
71 children.removeElementAt(childIndex);
72 child.setParent(null);
73 }
74
75 public void add(MutableTreeNode newChild) {
76 if(newChild.getParent() == this && newChild != null)
77 insert(newChild, getChildCount() - 1);
78 else
79 insert(newChild, getChildCount());
80 }
81
82 public void setParent(MutableTreeNode newParent) {
83 parent = newParent;
84 }
85
86 public TreeNode getParent() {
87 return parent;
88 }
89
90 public void removeFromParent() {
91 MutableTreeNode parent = (MutableTreeNode) getParent();
92 parent.remove(this);
93 }
94
95 public TreeNode getChildAt(int index) {
96 return (TreeNode) children.elementAt(index);
97 }
98
99 public int getChildCount() {
100 if (children == null)
101 return 0;
102 else
103 return children.size();
104 }
105
106 public int getIndex(TreeNode aChild) {
107 return children.indexOf(aChild);
108 }
109
110 public Enumeration children() {
111 if (children != null)
112 return children.elements();
113 else
114 return EMPTY_ENUMERATION;
115 }
116
117 public boolean getAllowsChildren() {
118 return allowsChildren;
119 }
120
121 public void setAllowsChildren(boolean allows) {
122 if (allows != allowsChildren) {
123 allowsChildren = allows;
124 if (!allowsChildren) {
125 removeAllChildren();
126 }
127 }
128 }
129
130 public Object getUserObject() {
131 return userObject;
132 }
133
134 public void setUserObject(Object userObject) {
135 this.userObject = userObject;
136 }
137
138 public void remove(MutableTreeNode aChild) {
139 remove(getIndex(aChild));
140 }
141
142 public void removeAllChildren() {
143 for (int i = getChildCount() - 1; i >= 0; i--) {
144 remove(i);
145 }
146 }
147
148 public boolean isLeaf() {
149 return getChildCount() > 0;
150 }
151
152 public TreeNode[] getPath() {
153 ArrayList path = new ArrayList ();
154 TreeNode current = this;
155 while (current!=null) {
156 path.add(0,current);
157 current = current.getParent();
158 }
159 return (TreeNode[])path.toArray(new TreeNode[0]);
160 }
161
162
163 public boolean isNodeAncestor(TreeNode anotherNode) {
164 TreeNode ancestor = this;
165 while (ancestor != null) {
166 if (ancestor == anotherNode) {
167 return true;
168 }
169 ancestor = ancestor.getParent();
170 }
171 return false;
172 }
173
174 public boolean isNodeDescendant(DefaultMutableTreeNode anotherNode) {
175 return anotherNode.isNodeAncestor(this);
176 }
177
178 public TreeNode getRoot() {
179 TreeNode anc = this;
180 TreeNode previous;
181 previous = anc;
182 while (anc != null) {
183 anc = anc.getParent();
184 }
185 return previous;
186 }
187
188 public boolean isRoot() {
189 return getParent() == null;
190 }
191
192 public String toString() {
193 if (userObject == null) {
194 return null;
195 } else {
196 return userObject.toString();
197 }
198 }
199 }
200 |
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