001/* AttributedCharacterIterator.java -- Iterate over attributes
002   Copyright (C) 1998, 1999, 2004, 2006, Free Software Foundation, Inc.
003
004This file is part of GNU Classpath.
005
006GNU Classpath is free software; you can redistribute it and/or modify
007it under the terms of the GNU General Public License as published by
008the Free Software Foundation; either version 2, or (at your option)
009any later version.
010
011GNU Classpath is distributed in the hope that it will be useful, but
012WITHOUT ANY WARRANTY; without even the implied warranty of
013MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014General Public License for more details.
015
016You should have received a copy of the GNU General Public License
017along with GNU Classpath; see the file COPYING.  If not, write to the
018Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
01902110-1301 USA.
020
021Linking this library statically or dynamically with other modules is
022making a combined work based on this library.  Thus, the terms and
023conditions of the GNU General Public License cover the whole
024combination.
025
026As a special exception, the copyright holders of this library give you
027permission to link this library with independent modules to produce an
028executable, regardless of the license terms of these independent
029modules, and to copy and distribute the resulting executable under
030terms of your choice, provided that you also meet, for each linked
031independent module, the terms and conditions of the license of that
032module.  An independent module is a module which is not derived from
033or based on this library.  If you modify this library, you may extend
034this exception to your version of the library, but you are not
035obligated to do so.  If you do not wish to do so, delete this
036exception statement from your version. */
037
038
039package java.text;
040
041import java.io.InvalidObjectException;
042import java.io.Serializable;
043import java.util.Map;
044import java.util.Set;
045
046/**
047 * This interface extends the <code>CharacterIterator</code> interface
048 * in order to support iteration over character attributes as well as
049 * over the characters themselves.
050 * <p>
051 * In addition to attributes of specific characters, this interface
052 * supports the concept of the "attribute run", which is an attribute
053 * that is defined for a particular value across an entire range of
054 * characters or which is undefined over a range of characters.
055 *
056 * @since 1.2
057 *
058 * @author Aaron M. Renn (arenn@urbanophile.com)
059 * @since 1.2
060 */
061public interface AttributedCharacterIterator extends CharacterIterator
062{
063  /**
064   * Defines attribute keys that are used as text attributes.
065   */
066  public static class Attribute implements Serializable
067  {
068    private static final long serialVersionUID = -9142742483513960612L;
069
070    /**
071     * This is the attribute for the language of the text.  The value of
072     * attributes of this key type are instances of <code>Locale</code>.
073     */
074    public static final Attribute LANGUAGE = new Attribute("language");
075
076    /**
077     * This is the attribute for the reading form of text.  This is used
078     * for storing pronunciation along with the written text for languages
079     * which need it.  The value of attributes of this key type are
080     * instances of <code>Annotation</code> which wrappers a
081     * <code>String</code>.
082     */
083    public static final Attribute READING = new Attribute("reading");
084
085    /**
086     * This is the attribute for input method segments.  The value of attributes
087     * of this key type are instances of <code>Annotation</code> which wrapper
088     * a <code>String</code>.
089     */
090    public static final Attribute INPUT_METHOD_SEGMENT =
091      new Attribute("input_method_segment");
092
093    /**
094     * The name of the attribute key
095     * @serial
096     */
097    private String name;
098
099    /**
100     * Initializes a new instance of this class with the specified name.
101     *
102     * @param name The name of this attribute key.
103     */
104    protected Attribute(String name)
105    {
106      this.name = name;
107    }
108
109    /**
110     * Returns the name of this attribute.
111     *
112     * @return The attribute name
113     */
114    protected String getName()
115    {
116      return name;
117    }
118
119    /**
120     * Resolves an instance of
121     * <code>AttributedCharacterIterator.Attribute</code>
122     * that is being deserialized to one of the three pre-defined attribute
123     * constants.  It does this by comparing the names of the attributes.  The
124     * constant that the deserialized object resolves to is returned.
125     *
126     * @return The resolved contant value
127     *
128     * @exception InvalidObjectException If the object being deserialized
129     *            cannot be resolved.
130     */
131    protected Object readResolve() throws InvalidObjectException
132    {
133      if (getName().equals(READING.getName()))
134        return READING;
135
136      if (getName().equals(LANGUAGE.getName()))
137        return LANGUAGE;
138
139      if (getName().equals(INPUT_METHOD_SEGMENT.getName()))
140        return INPUT_METHOD_SEGMENT;
141
142      throw new InvalidObjectException ("Can't resolve Attribute: "
143              + getName());
144    }
145
146    /**
147     * Tests this object for equality against the specified object.
148     * The two objects will be considered equal if and only if:
149     * <ul>
150     * <li>The specified object is not <code>null</code>.
151     * <li>The specified object is an instance of
152     * <code>AttributedCharacterIterator.Attribute</code>.
153     * <li>The specified object has the same attribute name as this object.
154     * </ul>
155     *
156     * @param obj  the <code>Object</code> to test for equality against this
157     *             object.
158     *
159     * @return <code>true</code> if the specified object is equal to this one,
160     *         <code>false</code> otherwise.
161     */
162    public final boolean equals(Object obj)
163    {
164      if (obj == this)
165        return true;
166      else
167        return false;
168    }
169
170    /**
171     * Returns a hash value for this object.
172     *
173     * @return A hash value for this object.
174     */
175    public final int hashCode()
176    {
177      return super.hashCode();
178    }
179
180    /**
181     * Returns a <code>String</code> representation of this object.
182     *
183     * @return A <code>String</code> representation of this object.
184     */
185    public String toString()
186    {
187      return getClass().getName() + "(" + getName() + ")";
188    }
189
190  } // Inner class Attribute
191
192  /**
193   * Returns a list of all keys that are defined for the
194   * text range.  This can be an empty list if no attributes are defined.
195   *
196   * @return A list of keys
197   */
198  Set<Attribute> getAllAttributeKeys();
199
200  /**
201   * Returns a <code>Map</code> of the attributes defined for the current
202   * character.
203   *
204   * @return A <code>Map</code> of the attributes for the current character.
205   */
206  Map<Attribute, Object> getAttributes();
207
208  /**
209   * Returns the value of the specified attribute for the
210   * current character.  If the attribute is not defined for the current
211   * character, <code>null</code> is returned.
212   *
213   * @param attrib The attribute to retrieve the value of.
214   *
215   * @return The value of the specified attribute
216   */
217  Object getAttribute(AttributedCharacterIterator.Attribute attrib);
218
219  /**
220   * Returns the index of the first character in the run that
221   * contains all attributes defined for the current character.
222   *
223   * @return The start index of the run
224   */
225  int getRunStart();
226
227  /**
228   * Returns the index of the first character in the run that
229   * contains all attributes in the specified <code>Set</code> defined for
230   * the current character.
231   *
232   * @param attribs The <code>Set</code> of attributes.
233   *
234   * @return The start index of the run.
235   */
236  int getRunStart(Set<? extends Attribute> attribs);
237
238  /**
239   * Returns the index of the first character in the run that
240   * contains the specified attribute defined for the current character.
241   *
242   * @param attrib The attribute.
243   *
244   * @return The start index of the run.
245   */
246  int getRunStart(AttributedCharacterIterator.Attribute attrib);
247
248  /**
249   * Returns the index of the character after the end of the run
250   * that contains all attributes defined for the current character.
251   *
252   * @return The end index of the run.
253   */
254  int getRunLimit();
255
256  /**
257   * Returns the index of the character after the end of the run
258   * that contains all attributes in the specified <code>Set</code> defined
259   * for the current character.
260   *
261   * @param attribs The <code>Set</code> of attributes.
262   *
263   * @return The end index of the run.
264   */
265  int getRunLimit(Set<? extends Attribute> attribs);
266
267  /**
268   * Returns the index of the character after the end of the run
269   * that contains the specified attribute defined for the current character.
270   *
271   * @param attrib The attribute.
272   *
273   * @return The end index of the run.
274   */
275  int getRunLimit(AttributedCharacterIterator.Attribute attrib);
276
277} // interface AttributedCharacterIterator