1/*
2 * Copyright (c) 2000, 2005, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.  Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26// Attributes.java - attribute list with Namespace support
27// http://www.saxproject.org
28// Written by David Megginson
29// NO WARRANTY!  This class is in the public domain.
30// $Id: Attributes.java,v 1.2 2004/11/03 22:44:51 jsuttor Exp $
31
32package org.xml.sax;
33
34
35/**
36 * Interface for a list of XML attributes.
37 *
38 * <blockquote>
39 * <em>This module, both source code and documentation, is in the
40 * Public Domain, and comes with <strong>NO WARRANTY</strong>.</em>
41 * See <a href='http://www.saxproject.org'>http://www.saxproject.org</a>
42 * for further information.
43 * </blockquote>
44 *
45 * <p>This interface allows access to a list of attributes in
46 * three different ways:</p>
47 *
48 * <ol>
49 * <li>by attribute index;</li>
50 * <li>by Namespace-qualified name; or</li>
51 * <li>by qualified (prefixed) name.</li>
52 * </ol>
53 *
54 * <p>The list will not contain attributes that were declared
55 * #IMPLIED but not specified in the start tag.  It will also not
56 * contain attributes used as Namespace declarations (xmlns*) unless
57 * the <code>http://xml.org/sax/features/namespace-prefixes</code>
58 * feature is set to <var>true</var> (it is <var>false</var> by
59 * default).
60 * Because SAX2 conforms to the original "Namespaces in XML"
61 * recommendation, it normally does not
62 * give namespace declaration attributes a namespace URI.
63 * </p>
64 *
65 * <p>Some SAX2 parsers may support using an optional feature flag
66 * (<code>http://xml.org/sax/features/xmlns-uris</code>) to request
67 * that those attributes be given URIs, conforming to a later
68 * backwards-incompatible revision of that recommendation.  (The
69 * attribute's "local name" will be the prefix, or "xmlns" when
70 * defining a default element namespace.)  For portability, handler
71 * code should always resolve that conflict, rather than requiring
72 * parsers that can change the setting of that feature flag.  </p>
73 *
74 * <p>If the namespace-prefixes feature (see above) is
75 * <var>false</var>, access by qualified name may not be available; if
76 * the <code>http://xml.org/sax/features/namespaces</code> feature is
77 * <var>false</var>, access by Namespace-qualified names may not be
78 * available.</p>
79 *
80 * <p>This interface replaces the now-deprecated SAX1 {@link
81 * org.xml.sax.AttributeList AttributeList} interface, which does not
82 * contain Namespace support.  In addition to Namespace support, it
83 * adds the <var>getIndex</var> methods (below).</p>
84 *
85 * <p>The order of attributes in the list is unspecified, and will
86 * vary from implementation to implementation.</p>
87 *
88 * @since 1.4, SAX 2.0
89 * @author David Megginson
90 * @see org.xml.sax.helpers.AttributesImpl
91 * @see org.xml.sax.ext.DeclHandler#attributeDecl
92 */
93public interface Attributes
94{
95
96
97    ////////////////////////////////////////////////////////////////////
98    // Indexed access.
99    ////////////////////////////////////////////////////////////////////
100
101
102    /**
103     * Return the number of attributes in the list.
104     *
105     * <p>Once you know the number of attributes, you can iterate
106     * through the list.</p>
107     *
108     * @return The number of attributes in the list.
109     * @see #getURI(int)
110     * @see #getLocalName(int)
111     * @see #getQName(int)
112     * @see #getType(int)
113     * @see #getValue(int)
114     */
115    public abstract int getLength ();
116
117
118    /**
119     * Look up an attribute's Namespace URI by index.
120     *
121     * @param index The attribute index (zero-based).
122     * @return The Namespace URI, or the empty string if none
123     *         is available, or null if the index is out of
124     *         range.
125     * @see #getLength
126     */
127    public abstract String getURI (int index);
128
129
130    /**
131     * Look up an attribute's local name by index.
132     *
133     * @param index The attribute index (zero-based).
134     * @return The local name, or the empty string if Namespace
135     *         processing is not being performed, or null
136     *         if the index is out of range.
137     * @see #getLength
138     */
139    public abstract String getLocalName (int index);
140
141
142    /**
143     * Look up an attribute's XML qualified (prefixed) name by index.
144     *
145     * @param index The attribute index (zero-based).
146     * @return The XML qualified name, or the empty string
147     *         if none is available, or null if the index
148     *         is out of range.
149     * @see #getLength
150     */
151    public abstract String getQName (int index);
152
153
154    /**
155     * Look up an attribute's type by index.
156     *
157     * <p>The attribute type is one of the strings "CDATA", "ID",
158     * "IDREF", "IDREFS", "NMTOKEN", "NMTOKENS", "ENTITY", "ENTITIES",
159     * or "NOTATION" (always in upper case).</p>
160     *
161     * <p>If the parser has not read a declaration for the attribute,
162     * or if the parser does not report attribute types, then it must
163     * return the value "CDATA" as stated in the XML 1.0 Recommendation
164     * (clause 3.3.3, "Attribute-Value Normalization").</p>
165     *
166     * <p>For an enumerated attribute that is not a notation, the
167     * parser will report the type as "NMTOKEN".</p>
168     *
169     * @param index The attribute index (zero-based).
170     * @return The attribute's type as a string, or null if the
171     *         index is out of range.
172     * @see #getLength
173     */
174    public abstract String getType (int index);
175
176
177    /**
178     * Look up an attribute's value by index.
179     *
180     * <p>If the attribute value is a list of tokens (IDREFS,
181     * ENTITIES, or NMTOKENS), the tokens will be concatenated
182     * into a single string with each token separated by a
183     * single space.</p>
184     *
185     * @param index The attribute index (zero-based).
186     * @return The attribute's value as a string, or null if the
187     *         index is out of range.
188     * @see #getLength
189     */
190    public abstract String getValue (int index);
191
192
193
194    ////////////////////////////////////////////////////////////////////
195    // Name-based query.
196    ////////////////////////////////////////////////////////////////////
197
198
199    /**
200     * Look up the index of an attribute by Namespace name.
201     *
202     * @param uri The Namespace URI, or the empty string if
203     *        the name has no Namespace URI.
204     * @param localName The attribute's local name.
205     * @return The index of the attribute, or -1 if it does not
206     *         appear in the list.
207     */
208    public int getIndex (String uri, String localName);
209
210
211    /**
212     * Look up the index of an attribute by XML qualified (prefixed) name.
213     *
214     * @param qName The qualified (prefixed) name.
215     * @return The index of the attribute, or -1 if it does not
216     *         appear in the list.
217     */
218    public int getIndex (String qName);
219
220
221    /**
222     * Look up an attribute's type by Namespace name.
223     *
224     * <p>See {@link #getType(int) getType(int)} for a description
225     * of the possible types.</p>
226     *
227     * @param uri The Namespace URI, or the empty String if the
228     *        name has no Namespace URI.
229     * @param localName The local name of the attribute.
230     * @return The attribute type as a string, or null if the
231     *         attribute is not in the list or if Namespace
232     *         processing is not being performed.
233     */
234    public abstract String getType (String uri, String localName);
235
236
237    /**
238     * Look up an attribute's type by XML qualified (prefixed) name.
239     *
240     * <p>See {@link #getType(int) getType(int)} for a description
241     * of the possible types.</p>
242     *
243     * @param qName The XML qualified name.
244     * @return The attribute type as a string, or null if the
245     *         attribute is not in the list or if qualified names
246     *         are not available.
247     */
248    public abstract String getType (String qName);
249
250
251    /**
252     * Look up an attribute's value by Namespace name.
253     *
254     * <p>See {@link #getValue(int) getValue(int)} for a description
255     * of the possible values.</p>
256     *
257     * @param uri The Namespace URI, or the empty String if the
258     *        name has no Namespace URI.
259     * @param localName The local name of the attribute.
260     * @return The attribute value as a string, or null if the
261     *         attribute is not in the list.
262     */
263    public abstract String getValue (String uri, String localName);
264
265
266    /**
267     * Look up an attribute's value by XML qualified (prefixed) name.
268     *
269     * <p>See {@link #getValue(int) getValue(int)} for a description
270     * of the possible values.</p>
271     *
272     * @param qName The XML qualified name.
273     * @return The attribute value as a string, or null if the
274     *         attribute is not in the list or if qualified names
275     *         are not available.
276     */
277    public abstract String getValue (String qName);
278
279}
280
281// end of Attributes.java
282