001 // SAX Attribute List Interface.
002 // http://www.saxproject.org
003 // No warranty; no copyright -- use this as you will.
004 // $Id: AttributeList.java,v 1.1 2004/12/23 22:38:42 mark Exp $
005
006 package org.xml.sax;
007
008 /**
009 * Interface for an element's attribute specifications.
010 *
011 * <blockquote>
012 * <em>This module, both source code and documentation, is in the
013 * Public Domain, and comes with <strong>NO WARRANTY</strong>.</em>
014 * See <a href='http://www.saxproject.org'>http://www.saxproject.org</a>
015 * for further information.
016 * </blockquote>
017 *
018 * <p>This is the original SAX1 interface for reporting an element's
019 * attributes. Unlike the new {@link org.xml.sax.Attributes Attributes}
020 * interface, it does not support Namespace-related information.</p>
021 *
022 * <p>When an attribute list is supplied as part of a
023 * {@link org.xml.sax.DocumentHandler#startElement startElement}
024 * event, the list will return valid results only during the
025 * scope of the event; once the event handler returns control
026 * to the parser, the attribute list is invalid. To save a
027 * persistent copy of the attribute list, use the SAX1
028 * {@link org.xml.sax.helpers.AttributeListImpl AttributeListImpl}
029 * helper class.</p>
030 *
031 * <p>An attribute list includes only attributes that have been
032 * specified or defaulted: #IMPLIED attributes will not be included.</p>
033 *
034 * <p>There are two ways for the SAX application to obtain information
035 * from the AttributeList. First, it can iterate through the entire
036 * list:</p>
037 *
038 * <pre>
039 * public void startElement (String name, AttributeList atts) {
040 * for (int i = 0; i < atts.getLength(); i++) {
041 * String name = atts.getName(i);
042 * String type = atts.getType(i);
043 * String value = atts.getValue(i);
044 * [...]
045 * }
046 * }
047 * </pre>
048 *
049 * <p>(Note that the result of getLength() will be zero if there
050 * are no attributes.)
051 *
052 * <p>As an alternative, the application can request the value or
053 * type of specific attributes:</p>
054 *
055 * <pre>
056 * public void startElement (String name, AttributeList atts) {
057 * String identifier = atts.getValue("id");
058 * String label = atts.getValue("label");
059 * [...]
060 * }
061 * </pre>
062 *
063 * @deprecated This interface has been replaced by the SAX2
064 * {@link org.xml.sax.Attributes Attributes}
065 * interface, which includes Namespace support.
066 * @since SAX 1.0
067 * @author David Megginson
068 * @version 2.0.1 (sax2r2)
069 * @see org.xml.sax.DocumentHandler#startElement startElement
070 * @see org.xml.sax.helpers.AttributeListImpl AttributeListImpl
071 */
072 public interface AttributeList {
073
074
075 ////////////////////////////////////////////////////////////////////
076 // Iteration methods.
077 ////////////////////////////////////////////////////////////////////
078
079
080 /**
081 * Return the number of attributes in this list.
082 *
083 * <p>The SAX parser may provide attributes in any
084 * arbitrary order, regardless of the order in which they were
085 * declared or specified. The number of attributes may be
086 * zero.</p>
087 *
088 * @return The number of attributes in the list.
089 */
090 public abstract int getLength ();
091
092
093 /**
094 * Return the name of an attribute in this list (by position).
095 *
096 * <p>The names must be unique: the SAX parser shall not include the
097 * same attribute twice. Attributes without values (those declared
098 * #IMPLIED without a value specified in the start tag) will be
099 * omitted from the list.</p>
100 *
101 * <p>If the attribute name has a namespace prefix, the prefix
102 * will still be attached.</p>
103 *
104 * @param i The index of the attribute in the list (starting at 0).
105 * @return The name of the indexed attribute, or null
106 * if the index is out of range.
107 * @see #getLength
108 */
109 public abstract String getName (int i);
110
111
112 /**
113 * Return the type of an attribute in the list (by position).
114 *
115 * <p>The attribute type is one of the strings "CDATA", "ID",
116 * "IDREF", "IDREFS", "NMTOKEN", "NMTOKENS", "ENTITY", "ENTITIES",
117 * or "NOTATION" (always in upper case).</p>
118 *
119 * <p>If the parser has not read a declaration for the attribute,
120 * or if the parser does not report attribute types, then it must
121 * return the value "CDATA" as stated in the XML 1.0 Recommentation
122 * (clause 3.3.3, "Attribute-Value Normalization").</p>
123 *
124 * <p>For an enumerated attribute that is not a notation, the
125 * parser will report the type as "NMTOKEN".</p>
126 *
127 * @param i The index of the attribute in the list (starting at 0).
128 * @return The attribute type as a string, or
129 * null if the index is out of range.
130 * @see #getLength
131 * @see #getType(java.lang.String)
132 */
133 public abstract String getType (int i);
134
135
136 /**
137 * Return the value of an attribute in the list (by position).
138 *
139 * <p>If the attribute value is a list of tokens (IDREFS,
140 * ENTITIES, or NMTOKENS), the tokens will be concatenated
141 * into a single string separated by whitespace.</p>
142 *
143 * @param i The index of the attribute in the list (starting at 0).
144 * @return The attribute value as a string, or
145 * null if the index is out of range.
146 * @see #getLength
147 * @see #getValue(java.lang.String)
148 */
149 public abstract String getValue (int i);
150
151
152
153 ////////////////////////////////////////////////////////////////////
154 // Lookup methods.
155 ////////////////////////////////////////////////////////////////////
156
157
158 /**
159 * Return the type of an attribute in the list (by name).
160 *
161 * <p>The return value is the same as the return value for
162 * getType(int).</p>
163 *
164 * <p>If the attribute name has a namespace prefix in the document,
165 * the application must include the prefix here.</p>
166 *
167 * @param name The name of the attribute.
168 * @return The attribute type as a string, or null if no
169 * such attribute exists.
170 * @see #getType(int)
171 */
172 public abstract String getType (String name);
173
174
175 /**
176 * Return the value of an attribute in the list (by name).
177 *
178 * <p>The return value is the same as the return value for
179 * getValue(int).</p>
180 *
181 * <p>If the attribute name has a namespace prefix in the document,
182 * the application must include the prefix here.</p>
183 *
184 * @param name the name of the attribute to return
185 * @return The attribute value as a string, or null if
186 * no such attribute exists.
187 * @see #getValue(int)
188 */
189 public abstract String getValue (String name);
190
191 }
192
193 // end of AttributeList.java