1// SAX default implementation for AttributeList.
2// http://www.saxproject.org
3// No warranty; no copyright -- use this as you will.
4// $Id: AttributeListImpl.java,v 1.6 2002/01/30 20:52:22 dbrownell Exp $
5
6package org.xml.sax.helpers;
7
8import java.util.ArrayList;
9import org.xml.sax.AttributeList;
10
11
12/**
13 * Default implementation for AttributeList.
14 *
15 * <blockquote>
16 * <em>This module, both source code and documentation, is in the
17 * Public Domain, and comes with <strong>NO WARRANTY</strong>.</em>
18 * See <a href='http://www.saxproject.org'>http://www.saxproject.org</a>
19 * for further information.
20 * </blockquote>
21 *
22 * <p>AttributeList implements the deprecated SAX1 {@link
23 * org.xml.sax.AttributeList AttributeList} interface, and has been
24 * replaced by the new SAX2 {@link org.xml.sax.helpers.AttributesImpl
25 * AttributesImpl} interface.</p>
26 *
27 * <p>This class provides a convenience implementation of the SAX
28 * {@link org.xml.sax.AttributeList AttributeList} interface.  This
29 * implementation is useful both for SAX parser writers, who can use
30 * it to provide attributes to the application, and for SAX application
31 * writers, who can use it to create a persistent copy of an element's
32 * attribute specifications:</p>
33 *
34 * <pre>
35 * private AttributeList myatts;
36 *
37 * public void startElement (String name, AttributeList atts)
38 * {
39 *              // create a persistent copy of the attribute list
40 *              // for use outside this method
41 *   myatts = new AttributeListImpl(atts);
42 *   [...]
43 * }
44 * </pre>
45 *
46 * <p>Please note that SAX parsers are not required to use this
47 * class to provide an implementation of AttributeList; it is
48 * supplied only as an optional convenience.  In particular,
49 * parser writers are encouraged to invent more efficient
50 * implementations.</p>
51 *
52 * @deprecated This class implements a deprecated interface,
53 *             {@link org.xml.sax.AttributeList AttributeList};
54 *             that interface has been replaced by
55 *             {@link org.xml.sax.Attributes Attributes},
56 *             which is implemented in the
57 *             {@link org.xml.sax.helpers.AttributesImpl
58 *            AttributesImpl} helper class.
59 * @since SAX 1.0
60 * @author David Megginson
61 * @version 2.0.1 (sax2r2)
62 * @see org.xml.sax.AttributeList
63 * @see org.xml.sax.DocumentHandler#startElement
64 */
65@Deprecated
66public class AttributeListImpl implements AttributeList
67{
68
69    /**
70     * Create an empty attribute list.
71     *
72     * <p>This constructor is most useful for parser writers, who
73     * will use it to create a single, reusable attribute list that
74     * can be reset with the clear method between elements.</p>
75     *
76     * @see #addAttribute
77     * @see #clear
78     */
79    public AttributeListImpl ()
80    {
81    }
82
83
84    /**
85     * Construct a persistent copy of an existing attribute list.
86     *
87     * <p>This constructor is most useful for application writers,
88     * who will use it to create a persistent copy of an existing
89     * attribute list.</p>
90     *
91     * @param atts The attribute list to copy
92     * @see org.xml.sax.DocumentHandler#startElement
93     */
94    public AttributeListImpl (AttributeList atts)
95    {
96    setAttributeList(atts);
97    }
98
99
100
101    ////////////////////////////////////////////////////////////////////
102    // Methods specific to this class.
103    ////////////////////////////////////////////////////////////////////
104
105
106    /**
107     * Set the attribute list, discarding previous contents.
108     *
109     * <p>This method allows an application writer to reuse an
110     * attribute list easily.</p>
111     *
112     * @param atts The attribute list to copy.
113     */
114    public void setAttributeList (AttributeList atts)
115    {
116    int count = atts.getLength();
117
118    clear();
119
120    for (int i = 0; i < count; i++) {
121        addAttribute(atts.getName(i), atts.getType(i), atts.getValue(i));
122    }
123    }
124
125
126    /**
127     * Add an attribute to an attribute list.
128     *
129     * <p>This method is provided for SAX parser writers, to allow them
130     * to build up an attribute list incrementally before delivering
131     * it to the application.</p>
132     *
133     * @param name The attribute name.
134     * @param type The attribute type ("NMTOKEN" for an enumeration).
135     * @param value The attribute value (must not be null).
136     * @see #removeAttribute
137     * @see org.xml.sax.DocumentHandler#startElement
138     */
139    public void addAttribute(String name, String type, String value) {
140        names.add(name);
141        types.add(type);
142        values.add(value);
143    }
144
145
146    /**
147     * Remove an attribute from the list.
148     *
149     * <p>SAX application writers can use this method to filter an
150     * attribute out of an AttributeList.  Note that invoking this
151     * method will change the length of the attribute list and
152     * some of the attribute's indices.</p>
153     *
154     * <p>If the requested attribute is not in the list, this is
155     * a no-op.</p>
156     *
157     * @param name The attribute name.
158     * @see #addAttribute
159     */
160    public void removeAttribute(String name) {
161        int i = names.indexOf(name);
162        if (i != -1) {
163            names.remove(i);
164            types.remove(i);
165            values.remove(i);
166        }
167    }
168
169
170    /**
171     * Clear the attribute list.
172     *
173     * <p>SAX parser writers can use this method to reset the attribute
174     * list between DocumentHandler.startElement events.  Normally,
175     * it will make sense to reuse the same AttributeListImpl object
176     * rather than allocating a new one each time.</p>
177     *
178     * @see org.xml.sax.DocumentHandler#startElement
179     */
180    public void clear() {
181        names.clear();
182        types.clear();
183        values.clear();
184    }
185
186
187
188    ////////////////////////////////////////////////////////////////////
189    // Implementation of org.xml.sax.AttributeList
190    ////////////////////////////////////////////////////////////////////
191
192
193    /**
194     * Return the number of attributes in the list.
195     *
196     * @return The number of attributes in the list.
197     * @see org.xml.sax.AttributeList#getLength
198     */
199    public int getLength() {
200        return names.size();
201    }
202
203
204    /**
205     * Get the name of an attribute (by position).
206     *
207     * @param i The position of the attribute in the list.
208     * @return The attribute name as a string, or null if there
209     *         is no attribute at that position.
210     * @see org.xml.sax.AttributeList#getName(int)
211     */
212    public String getName(int i) {
213        if (i < 0 || i >= names.size()) {
214            return null;
215        }
216        return names.get(i);
217    }
218
219
220    /**
221     * Get the type of an attribute (by position).
222     *
223     * @param i The position of the attribute in the list.
224     * @return The attribute type as a string ("NMTOKEN" for an
225     *         enumeration, and "CDATA" if no declaration was
226     *         read), or null if there is no attribute at
227     *         that position.
228     * @see org.xml.sax.AttributeList#getType(int)
229     */
230    public String getType(int i) {
231        if (i < 0 || i >= types.size()) {
232            return null;
233        }
234        return types.get(i);
235    }
236
237
238    /**
239     * Get the value of an attribute (by position).
240     *
241     * @param i The position of the attribute in the list.
242     * @return The attribute value as a string, or null if
243     *         there is no attribute at that position.
244     * @see org.xml.sax.AttributeList#getValue(int)
245     */
246    public String getValue(int i) {
247        if (i < 0 || i >= values.size()) {
248            return null;
249        }
250        return values.get(i);
251    }
252
253
254    /**
255     * Get the type of an attribute (by name).
256     *
257     * @param name The attribute name.
258     * @return The attribute type as a string ("NMTOKEN" for an
259     *         enumeration, and "CDATA" if no declaration was
260     *         read).
261     * @see org.xml.sax.AttributeList#getType(java.lang.String)
262     */
263    public String getType(String name) {
264        return getType(names.indexOf(name));
265    }
266
267
268    /**
269     * Get the value of an attribute (by name).
270     *
271     * @param name The attribute name.
272     * @return the named attribute's value or null, if the attribute does not
273     *         exist.
274     * @see org.xml.sax.AttributeList#getValue(java.lang.String)
275     */
276    public String getValue(String name) {
277        return getValue(names.indexOf(name));
278    }
279
280
281
282    ////////////////////////////////////////////////////////////////////
283    // Internal state.
284    ////////////////////////////////////////////////////////////////////
285
286    private ArrayList<String> names = new ArrayList<String>();
287    private ArrayList<String> types = new ArrayList<String>();
288    private ArrayList<String> values = new ArrayList<String>();
289
290}
291
292// end of AttributeListImpl.java
293