001 /* AttributeSet.java --
002 Copyright (C) 2002, 2004, 2005 Free Software Foundation, Inc.
003
004 This file is part of GNU Classpath.
005
006 GNU Classpath is free software; you can redistribute it and/or modify
007 it under the terms of the GNU General Public License as published by
008 the Free Software Foundation; either version 2, or (at your option)
009 any later version.
010
011 GNU Classpath is distributed in the hope that it will be useful, but
012 WITHOUT ANY WARRANTY; without even the implied warranty of
013 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
014 General Public License for more details.
015
016 You should have received a copy of the GNU General Public License
017 along with GNU Classpath; see the file COPYING. If not, write to the
018 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
019 02110-1301 USA.
020
021 Linking this library statically or dynamically with other modules is
022 making a combined work based on this library. Thus, the terms and
023 conditions of the GNU General Public License cover the whole
024 combination.
025
026 As a special exception, the copyright holders of this library give you
027 permission to link this library with independent modules to produce an
028 executable, regardless of the license terms of these independent
029 modules, and to copy and distribute the resulting executable under
030 terms of your choice, provided that you also meet, for each linked
031 independent module, the terms and conditions of the license of that
032 module. An independent module is a module which is not derived from
033 or based on this library. If you modify this library, you may extend
034 this exception to your version of the library, but you are not
035 obligated to do so. If you do not wish to do so, delete this
036 exception statement from your version. */
037
038 package javax.swing.text;
039
040 import java.util.Enumeration;
041
042 /**
043 * A set of attributes. An attribute has a key and a value. They typically
044 * describe features of a piece of text that make up its graphical
045 * representation.
046 *
047 * An <code>AttributeSet</code> may have a resolving parent,
048 * that is another <code>AttributeSet</code> that is searched for attribute
049 * keys that are not stored locally in this <code>AttributeSet</code>.
050 *
051 * @author original author unknown
052 * @author Roman Kennke (roman@kennke.org)
053 */
054 public interface AttributeSet
055 {
056 /**
057 * Used as keys to identify character-run attributes.
058 */
059 static interface CharacterAttribute
060 {
061 // This interface is a marker interface and has no methods.
062 }
063
064 /**
065 * Used as keys to identify color attributes.
066 */
067 static interface ColorAttribute
068 {
069 // This interface is a marker interface and has no methods.
070 }
071
072 /**
073 * Used as keys to identify font attributes.
074 */
075 static interface FontAttribute
076 {
077 // This interface is a marker interface and has no methods.
078 }
079
080 /**
081 * Used as keys to identify paragraph level attributes.
082 */
083 static interface ParagraphAttribute
084 {
085 // This interface is a marker interface and has no methods.
086 }
087
088 /**
089 * Key of the attribute that is used to describe the name of an
090 * <code>AttributeSet</code>.
091 */
092 Object NameAttribute = StyleConstants.NameAttribute;
093
094 /**
095 * Key of the attribute that is used to identify the resolving parent of
096 * an <code>AttributeSet</code>.
097 */
098 Object ResolveAttribute = StyleConstants.ResolveAttribute;
099
100 /**
101 * Returns <code>true</code> if this <code>AttributeSet</code> contains
102 * an attribute with the specified <code>name</code> and <code>value</code>,
103 * <code>false</code> otherwise.
104 *
105 * @param name the name of the requested attribute
106 * @param value the value of the requested attribute
107 *
108 * @return <code>true</code> if this <code>AttributeSet</code> contains
109 * an attribute with the specified <code>name</code> and
110 * <code>value</code>, <code>false</code> otherwise
111 */
112 boolean containsAttribute(Object name, Object value);
113
114 /**
115 * Returns <code>true</code> of this <code>AttributeSet</code> contains all
116 * of the specified <code>attributes</code>.
117 *
118 * @param attributes the requested attributes
119 *
120 * @return <code>true</code> of this <code>AttributeSet</code> contains all
121 * of the specified <code>attributes</code>
122 */
123 boolean containsAttributes(AttributeSet attributes);
124
125 /**
126 * Creates and returns a copy of this <code>AttributeSet</code>.
127 *
128 * @return a copy of this <code>AttributeSet</code>
129 */
130 AttributeSet copyAttributes();
131
132 /**
133 * Returns the attribute with the specified <code>key</code> or
134 * <code>null</code> if no such attribute is defined in this
135 * <code>AttributeSet</code> and its resolving parents.
136 *
137 * @param key the key of the attribute that is looked up
138 *
139 * @return the attribute with the specified <code>key</code> or
140 * <code>null</code> if no such attribute is defined in this
141 * <code>AttributeSet</code> and its resolving parents
142 */
143 Object getAttribute(Object key);
144
145 /**
146 * Returns the number of attributes that are stored locally in this
147 * <code>AttributeSet</code>.
148 *
149 * @return the number of attributes that are stored locally in this
150 * <code>AttributeSet</code>
151 */
152 int getAttributeCount();
153
154 /**
155 * Returns the names of the attributes that are stored in this
156 * <code>AttributeSet</code>.
157 *
158 * @return the names of the attributes that are stored in this
159 * <code>AttributeSet</code>
160 */
161 Enumeration<?> getAttributeNames();
162
163 /**
164 * Returns the resolving parent of this <code>AttributeSet</code>.
165 * If a key is not stored locally, then a {@link #getAttribute(Object)}
166 * request is resolved up in the resolving parent of this
167 * <code>AttributeSet</code>.
168 *
169 * @return the resolving parent of this <code>AttributeSet</code>
170 */
171 AttributeSet getResolveParent();
172
173 /**
174 * Returns <code>true</code> if an attribute with the specified name is
175 * defined locally in this <code>AttributeSet</code>, without resolving
176 * through the resolving parents.
177 *
178 * @return <code>true</code> if an attribute with the specified name is
179 * defined locally in this <code>AttributeSet</code>
180 */
181 boolean isDefined(Object attrName);
182
183 /**
184 * Returns <code>true</code> if all of the attributes in <code>attr</code>
185 * are equal to the attributes in this <code>AttributeSet</code>,
186 * <code>false</code> otherwise.
187 *
188 * @param attr the attributes to be compared to <code>this</code>
189 *
190 * @return <code>true</code> if all of the attributes in <code>attr</code>
191 * are equal to the attributes in this <code>AttributeSet</code>,
192 * <code>false</code> otherwise
193 */
194 boolean isEqual(AttributeSet attr);
195 }