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) 2002 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.xpath;
43
44
45 import org.w3c.dom.Node;
46 import org.w3c.dom.DOMException;
47
48 /**
49 * The <code>XPathResult</code> interface represents the result of the
50 * evaluation of an XPath 1.0 expression within the context of a particular
51 * node. Since evaluation of an XPath expression can result in various
52 * result types, this object makes it possible to discover and manipulate
53 * the type and value of the result.
54 * <p>See also the <a href='http://www.w3.org/2002/08/WD-DOM-Level-3-XPath-20020820'>Document Object Model (DOM) Level 3 XPath Specification</a>.
55 */
56 public interface XPathResult {
57 // XPathResultType
58 /**
59 * This code does not represent a specific type. An evaluation of an XPath
60 * expression will never produce this type. If this type is requested,
61 * then the evaluation returns whatever type naturally results from
62 * evaluation of the expression.
63 * <br>If the natural result is a node set when <code>ANY_TYPE</code> was
64 * requested, then <code>UNORDERED_NODE_ITERATOR_TYPE</code> is always
65 * the resulting type. Any other representation of a node set must be
66 * explicitly requested.
67 */
68 public static final short ANY_TYPE = 0;
69 /**
70 * The result is a number as defined by . Document modification does not
71 * invalidate the number, but may mean that reevaluation would not yield
72 * the same number.
73 */
74 public static final short NUMBER_TYPE = 1;
75 /**
76 * The result is a string as defined by . Document modification does not
77 * invalidate the string, but may mean that the string no longer
78 * corresponds to the current document.
79 */
80 public static final short STRING_TYPE = 2;
81 /**
82 * The result is a boolean as defined by . Document modification does not
83 * invalidate the boolean, but may mean that reevaluation would not
84 * yield the same boolean.
85 */
86 public static final short BOOLEAN_TYPE = 3;
87 /**
88 * The result is a node set as defined by that will be accessed
89 * iteratively, which may not produce nodes in a particular order.
90 * Document modification invalidates the iteration.
91 * <br>This is the default type returned if the result is a node set and
92 * <code>ANY_TYPE</code> is requested.
93 */
94 public static final short UNORDERED_NODE_ITERATOR_TYPE = 4;
95 /**
96 * The result is a node set as defined by that will be accessed
97 * iteratively, which will produce document-ordered nodes. Document
98 * modification invalidates the iteration.
99 */
100 public static final short ORDERED_NODE_ITERATOR_TYPE = 5;
101 /**
102 * The result is a node set as defined by that will be accessed as a
103 * snapshot list of nodes that may not be in a particular order.
104 * Document modification does not invalidate the snapshot but may mean
105 * that reevaluation would not yield the same snapshot and nodes in the
106 * snapshot may have been altered, moved, or removed from the document.
107 */
108 public static final short UNORDERED_NODE_SNAPSHOT_TYPE = 6;
109 /**
110 * The result is a node set as defined by that will be accessed as a
111 * snapshot list of nodes that will be in original document order.
112 * Document modification does not invalidate the snapshot but may mean
113 * that reevaluation would not yield the same snapshot and nodes in the
114 * snapshot may have been altered, moved, or removed from the document.
115 */
116 public static final short ORDERED_NODE_SNAPSHOT_TYPE = 7;
117 /**
118 * The result is a node set as defined by and will be accessed as a
119 * single node, which may be <code>null</code>if the node set is empty.
120 * Document modification does not invalidate the node, but may mean that
121 * the result node no longer corresponds to the current document. This
122 * is a convenience that permits optimization since the implementation
123 * can stop once any node in the in the resulting set has been found.
124 * <br>If there are more than one node in the actual result, the single
125 * node returned might not be the first in document order.
126 */
127 public static final short ANY_UNORDERED_NODE_TYPE = 8;
128 /**
129 * The result is a node set as defined by and will be accessed as a
130 * single node, which may be <code>null</code> if the node set is empty.
131 * Document modification does not invalidate the node, but may mean that
132 * the result node no longer corresponds to the current document. This
133 * is a convenience that permits optimization since the implementation
134 * can stop once the first node in document order of the resulting set
135 * has been found.
136 * <br>If there are more than one node in the actual result, the single
137 * node returned will be the first in document order.
138 */
139 public static final short FIRST_ORDERED_NODE_TYPE = 9;
140
141 /**
142 * A code representing the type of this result, as defined by the type
143 * constants.
144 */
145 public short getResultType();
146
147 /**
148 * The value of this number result. If the native double type of the DOM
149 * binding does not directly support the exact IEEE 754 result of the
150 * XPath expression, then it is up to the definition of the binding
151 * binding to specify how the XPath number is converted to the native
152 * binding number.
153 * @exception XPathException
154 * TYPE_ERR: raised if <code>resultType</code> is not
155 * <code>NUMBER_TYPE</code>.
156 */
157 public double getNumberValue()
158 throws XPathException;
159
160 /**
161 * The value of this string result.
162 * @exception XPathException
163 * TYPE_ERR: raised if <code>resultType</code> is not
164 * <code>STRING_TYPE</code>.
165 */
166 public String getStringValue()
167 throws XPathException;
168
169 /**
170 * The value of this boolean result.
171 * @exception XPathException
172 * TYPE_ERR: raised if <code>resultType</code> is not
173 * <code>BOOLEAN_TYPE</code>.
174 */
175 public boolean getBooleanValue()
176 throws XPathException;
177
178 /**
179 * The value of this single node result, which may be <code>null</code>.
180 * @exception XPathException
181 * TYPE_ERR: raised if <code>resultType</code> is not
182 * <code>ANY_UNORDERED_NODE_TYPE</code> or
183 * <code>FIRST_ORDERED_NODE_TYPE</code>.
184 */
185 public Node getSingleNodeValue()
186 throws XPathException;
187
188 /**
189 * Signifies that the iterator has become invalid. True if
190 * <code>resultType</code> is <code>UNORDERED_NODE_ITERATOR_TYPE</code>
191 * or <code>ORDERED_NODE_ITERATOR_TYPE</code> and the document has been
192 * modified since this result was returned.
193 */
194 public boolean getInvalidIteratorState();
195
196 /**
197 * The number of nodes in the result snapshot. Valid values for
198 * snapshotItem indices are <code>0</code> to
199 * <code>snapshotLength-1</code> inclusive.
200 * @exception XPathException
201 * TYPE_ERR: raised if <code>resultType</code> is not
202 * <code>UNORDERED_NODE_SNAPSHOT_TYPE</code> or
203 * <code>ORDERED_NODE_SNAPSHOT_TYPE</code>.
204 */
205 public int getSnapshotLength()
206 throws XPathException;
207
208 /**
209 * Iterates and returns the next node from the node set or
210 * <code>null</code>if there are no more nodes.
211 * @return Returns the next node.
212 * @exception XPathException
213 * TYPE_ERR: raised if <code>resultType</code> is not
214 * <code>UNORDERED_NODE_ITERATOR_TYPE</code> or
215 * <code>ORDERED_NODE_ITERATOR_TYPE</code>.
216 * @exception DOMException
217 * INVALID_STATE_ERR: The document has been mutated since the result was
218 * returned.
219 */
220 public Node iterateNext()
221 throws XPathException, DOMException;
222
223 /**
224 * Returns the <code>index</code>th item in the snapshot collection. If
225 * <code>index</code> is greater than or equal to the number of nodes in
226 * the list, this method returns <code>null</code>. Unlike the iterator
227 * result, the snapshot does not become invalid, but may not correspond
228 * to the current document if it is mutated.
229 * @param index Index into the snapshot collection.
230 * @return The node at the <code>index</code>th position in the
231 * <code>NodeList</code>, or <code>null</code> if that is not a valid
232 * index.
233 * @exception XPathException
234 * TYPE_ERR: raised if <code>resultType</code> is not
235 * <code>UNORDERED_NODE_SNAPSHOT_TYPE</code> or
236 * <code>ORDERED_NODE_SNAPSHOT_TYPE</code>.
237 */
238 public Node snapshotItem(int index)
239 throws XPathException;
240
241 }