1 /*
2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
3 *
4 * This code is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License version 2 only, as
6 * published by the Free Software Foundation. Oracle designates this
7 * particular file as subject to the "Classpath" exception as provided
8 * by Oracle in the LICENSE file that accompanied this code.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 */
24
25 /*
26 * This file is available under and governed by the GNU General Public
27 * License version 2 only, as published by the Free Software Foundation.
28 * However, the following notice accompanied the original version of this
29 * file and, per its terms, should not be removed:
30 *
31 * Copyright (c) 2000 World Wide Web Consortium,
32 * (Massachusetts Institute of Technology, Institut National de
33 * Recherche en Informatique et en Automatique, Keio University). All
34 * Rights Reserved. This program is distributed under the W3C's Software
35 * Intellectual Property License. This program is distributed in the
36 * hope that it will be useful, but WITHOUT ANY WARRANTY; without even
37 * the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
38 * PURPOSE.
39 * See W3C License http://www.w3.org/Consortium/Legal/ for more details.
40 */
41
42 package org.w3c.dom.traversal;
43
44 import org.w3c.dom.Node;
45
46 /**
47 * Filters are objects that know how to "filter out" nodes. If a
48 * <code>NodeIterator</code> or <code>TreeWalker</code> is given a
49 * <code>NodeFilter</code>, it applies the filter before it returns the next
50 * node. If the filter says to accept the node, the traversal logic returns
51 * it; otherwise, traversal looks for the next node and pretends that the
52 * node that was rejected was not there.
53 * <p>The DOM does not provide any filters. <code>NodeFilter</code> is just an
54 * interface that users can implement to provide their own filters.
55 * <p><code>NodeFilters</code> do not need to know how to traverse from node
56 * to node, nor do they need to know anything about the data structure that
57 * is being traversed. This makes it very easy to write filters, since the
58 * only thing they have to know how to do is evaluate a single node. One
59 * filter may be used with a number of different kinds of traversals,
60 * encouraging code reuse.
61 * <p>See also the <a href='http://www.w3.org/TR/2000/REC-DOM-Level-2-Traversal-Range-20001113'>Document Object Model (DOM) Level 2 Traversal and Range Specification</a>.
62 * @since 9, DOM Level 2
63 */
64 public interface NodeFilter {
65 // Constants returned by acceptNode
66 /**
67 * Accept the node. Navigation methods defined for
68 * <code>NodeIterator</code> or <code>TreeWalker</code> will return this
69 * node.
70 */
71 public static final short FILTER_ACCEPT = 1;
72 /**
73 * Reject the node. Navigation methods defined for
74 * <code>NodeIterator</code> or <code>TreeWalker</code> will not return
75 * this node. For <code>TreeWalker</code>, the children of this node
76 * will also be rejected. <code>NodeIterators</code> treat this as a
77 * synonym for <code>FILTER_SKIP</code>.
78 */
79 public static final short FILTER_REJECT = 2;
80 /**
81 * Skip this single node. Navigation methods defined for
82 * <code>NodeIterator</code> or <code>TreeWalker</code> will not return
83 * this node. For both <code>NodeIterator</code> and
84 * <code>TreeWalker</code>, the children of this node will still be
85 * considered.
86 */
87 public static final short FILTER_SKIP = 3;
88
89 // Constants for whatToShow
90 /**
91 * Show all <code>Nodes</code>.
92 */
93 public static final int SHOW_ALL = 0xFFFFFFFF;
94 /**
95 * Show <code>Element</code> nodes.
96 */
97 public static final int SHOW_ELEMENT = 0x00000001;
98 /**
99 * Show <code>Attr</code> nodes. This is meaningful only when creating an
100 * <code>NodeIterator</code> or <code>TreeWalker</code> with an
101 * attribute node as its <code>root</code>; in this case, it means that
102 * the attribute node will appear in the first position of the iteration
103 * or traversal. Since attributes are never children of other nodes,
104 * they do not appear when traversing over the document tree.
105 */
106 public static final int SHOW_ATTRIBUTE = 0x00000002;
107 /**
108 * Show <code>Text</code> nodes.
109 */
110 public static final int SHOW_TEXT = 0x00000004;
111 /**
112 * Show <code>CDATASection</code> nodes.
113 */
114 public static final int SHOW_CDATA_SECTION = 0x00000008;
115 /**
116 * Show <code>EntityReference</code> nodes.
117 */
118 public static final int SHOW_ENTITY_REFERENCE = 0x00000010;
119 /**
120 * Show <code>Entity</code> nodes. This is meaningful only when creating
121 * an <code>NodeIterator</code> or <code>TreeWalker</code> with an
122 * <code>Entity</code> node as its <code>root</code>; in this case, it
123 * means that the <code>Entity</code> node will appear in the first
124 * position of the traversal. Since entities are not part of the
125 * document tree, they do not appear when traversing over the document
126 * tree.
127 */
128 public static final int SHOW_ENTITY = 0x00000020;
129 /**
130 * Show <code>ProcessingInstruction</code> nodes.
131 */
132 public static final int SHOW_PROCESSING_INSTRUCTION = 0x00000040;
133 /**
134 * Show <code>Comment</code> nodes.
135 */
136 public static final int SHOW_COMMENT = 0x00000080;
137 /**
138 * Show <code>Document</code> nodes.
139 */
140 public static final int SHOW_DOCUMENT = 0x00000100;
141 /**
142 * Show <code>DocumentType</code> nodes.
143 */
144 public static final int SHOW_DOCUMENT_TYPE = 0x00000200;
145 /**
146 * Show <code>DocumentFragment</code> nodes.
147 */
148 public static final int SHOW_DOCUMENT_FRAGMENT = 0x00000400;
149 /**
150 * Show <code>Notation</code> nodes. This is meaningful only when creating
151 * an <code>NodeIterator</code> or <code>TreeWalker</code> with a
152 * <code>Notation</code> node as its <code>root</code>; in this case, it
153 * means that the <code>Notation</code> node will appear in the first
154 * position of the traversal. Since notations are not part of the
155 * document tree, they do not appear when traversing over the document
156 * tree.
157 */
158 public static final int SHOW_NOTATION = 0x00000800;
159
160 /**
161 * Test whether a specified node is visible in the logical view of a
162 * <code>TreeWalker</code> or <code>NodeIterator</code>. This function
163 * will be called by the implementation of <code>TreeWalker</code> and
164 * <code>NodeIterator</code>; it is not normally called directly from
165 * user code. (Though you could do so if you wanted to use the same
166 * filter to guide your own application logic.)
167 * @param n The node to check to see if it passes the filter or not.
168 * @return A constant to determine whether the node is accepted,
169 * rejected, or skipped, as defined above.
170 */
171 public short acceptNode(Node n);
172
173 }