gomp-20050608-branch/libjava/classpath/java/text/AttributedCharacterIterator.java

   1 /* AttributedCharacterIterator.java -- Iterate over attributes
   2    Copyright (C) 1998, 1999, 2004 Free Software Foundation, Inc.
   3
   4 This file is part of GNU Classpath.
   5
   6 GNU Classpath is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU Classpath is distributed in the hope that it will be useful, but
  12 WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Classpath; see the file COPYING.  If not, write to the
  18 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  19 02110-1301 USA.
  20
  21 Linking this library statically or dynamically with other modules is
  22 making a combined work based on this library.  Thus, the terms and
  23 conditions of the GNU General Public License cover the whole
  24 combination.
  25
  26 As a special exception, the copyright holders of this library give you
  27 permission to link this library with independent modules to produce an
  28 executable, regardless of the license terms of these independent
  29 modules, and to copy and distribute the resulting executable under
  30 terms of your choice, provided that you also meet, for each linked
  31 independent module, the terms and conditions of the license of that
  32 module.  An independent module is a module which is not derived from
  33 or based on this library.  If you modify this library, you may extend
  34 this exception to your version of the library, but you are not
  35 obligated to do so.  If you do not wish to do so, delete this
  36 exception statement from your version. */
  37
  38
  39 package java.text;
  40
  41 import java.io.InvalidObjectException;
  42 import java.io.Serializable;
  43 import java.util.Map;
  44 import java.util.Set;
  45
  46 /**
  47  * This interface extends the <code>CharacterIterator</code> interface
  48  * in order to support iteration over character attributes as well as
  49  * over the characters themselves.
  50  * <p>
  51  * In addition to attributes of specific characters, this interface
  52  * supports the concept of the "attribute run", which is an attribute
  53  * that is defined for a particular value across an entire range of
  54  * characters or which is undefined over a range of characters.
  55  *
  56  * @author Aaron M. Renn (arenn@urbanophile.com)
  57  */
  58 public interface AttributedCharacterIterator extends CharacterIterator
  59 {
  60   /**
  61    * Defines attribute keys that are used as text attributes.
  62    */
  63   public static class Attribute implements Serializable
  64   {
  65     private static final long serialVersionUID = -9142742483513960612L;
  66
  67     /**
  68      * This is the attribute for the language of the text.  The value of
  69      * attributes of this key type are instances of <code>Locale</code>.
  70      */
  71     public static final Attribute LANGUAGE = new Attribute ("LANGUAGE");
  72
  73     /**
  74      * This is the attribute for the reading form of text.  This is used
  75      * for storing pronunciation along with the written text for languages
  76      * which need it.  The value of attributes of this key type are
  77      * instances of <code>Annotation</code> which wrappers a
  78      * <code>String</code>.
  79      */
  80     public static final Attribute READING = new Attribute ("READING");
  81
  82     /**
  83      * This is the attribute for input method segments.  The value of attributes
  84      * of this key type are instances of <code>Annotation</code> which wrapper
  85      * a <code>String</code>.
  86      */
  87     public static final Attribute INPUT_METHOD_SEGMENT =
  88       new Attribute ("INPUT_METHOD_SEGMENT");
  89
  90     /**
  91      * The name of the attribute key
  92      * @serial
  93      */
  94     private String name;
  95
  96     /**
  97      * Initializes a new instance of this class with the specified name.
  98      *
  99      * @param name The name of this attribute key.
 100      */
 101     protected Attribute (String name)
 102     {
 103       this.name = name;
 104     }
 105
 106     /**
 107      * Returns the name of this attribute.
 108      *
 109      * @return The attribute name
 110      */
 111     protected String getName()
 112     {
 113       return name;
 114     }
 115
 116     /**
 117      * Resolves an instance of
 118      * <code>AttributedCharacterIterator.Attribute</code>
 119      * that is being deserialized to one of the three pre-defined attribute
 120      * constants.  It does this by comparing the names of the attributes.  The
 121      * constant that the deserialized object resolves to is returned.
 122      *
 123      * @return The resolved contant value
 124      *
 125      * @exception InvalidObjectException If the object being deserialized
 126      *            cannot be resolved.
 127      */
 128     protected Object readResolve() throws InvalidObjectException
 129     {
 130       if (this.equals (READING))
 131         return READING;
 132
 133       if (this.equals (LANGUAGE))
 134         return LANGUAGE;
 135
 136       if (this.equals (INPUT_METHOD_SEGMENT))
 137         return INPUT_METHOD_SEGMENT;
 138
 139       throw new InvalidObjectException ("Can't resolve Attribute: "
 140               + getName());
 141     }
 142
 143     /**
 144      * Tests this object for equality against the specified object.
 145      * The two objects will be considered equal if and only if:
 146      * <ul>
 147      * <li>The specified object is not <code>null</code>.
 148      * <li>The specified object is an instance of
 149      * <code>AttributedCharacterIterator.Attribute</code>.
 150      * <li>The specified object has the same attribute name as this object.
 151      * </ul>
 152      *
 153      * @param obj  the <code>Object</code> to test for equality against this
 154      *             object.
 155      *
 156      * @return <code>true</code> if the specified object is equal to this one,
 157      *         <code>false</code> otherwise.
 158      */
 159     public final boolean equals (Object obj)
 160     {
 161       if (obj == this)
 162         return true;
 163       else
 164         return false;
 165     }
 166
 167     /**
 168      * Returns a hash value for this object.
 169      *
 170      * @return A hash value for this object.
 171      */
 172     public final int hashCode()
 173     {
 174       return super.hashCode();
 175     }
 176
 177     /**
 178      * Returns a <code>String</code> representation of this object.
 179      *
 180      * @return A <code>String</code> representation of this object.
 181      */
 182     public String toString()
 183     {
 184       return getClass().getName() + "(" + getName() + ")";
 185     }
 186
 187   } // Inner class Attribute
 188
 189   /**
 190    * Returns a list of all keys that are defined for the
 191    * text range.  This can be an empty list if no attributes are defined.
 192    *
 193    * @return A list of keys
 194    */
 195   Set getAllAttributeKeys();
 196
 197   /**
 198    * Returns a <code>Map</code> of the attributes defined for the current
 199    * character.
 200    *
 201    * @return A <code>Map</code> of the attributes for the current character.
 202    */
 203   Map getAttributes();
 204
 205   /**
 206    * Returns the value of the specified attribute for the
 207    * current character.  If the attribute is not defined for the current
 208    * character, <code>null</code> is returned.
 209    *
 210    * @param attrib The attribute to retrieve the value of.
 211    *
 212    * @return The value of the specified attribute
 213    */
 214   Object getAttribute (AttributedCharacterIterator.Attribute attrib);
 215
 216   /**
 217    * Returns the index of the first character in the run that
 218    * contains all attributes defined for the current character.
 219    *
 220    * @return The start index of the run
 221    */
 222   int getRunStart();
 223
 224   /**
 225    * Returns the index of the first character in the run that
 226    * contains all attributes in the specified <code>Set</code> defined for
 227    * the current character.
 228    *
 229    * @param attribs The <code>Set</code> of attributes.
 230    *
 231    * @return The start index of the run.
 232    */
 233   int getRunStart (Set attribs);
 234
 235   /**
 236    * Returns the index of the first character in the run that
 237    * contains the specified attribute defined for the current character.
 238    *
 239    * @param attrib The attribute.
 240    *
 241    * @return The start index of the run.
 242    */
 243   int getRunStart (AttributedCharacterIterator.Attribute attrib);
 244
 245   /**
 246    * Returns the index of the character after the end of the run
 247    * that contains all attributes defined for the current character.
 248    *
 249    * @return The end index of the run.
 250    */
 251   int getRunLimit();
 252
 253   /**
 254    * Returns the index of the character after the end of the run
 255    * that contains all attributes in the specified <code>Set</code> defined
 256    * for the current character.
 257    *
 258    * @param attribs The <code>Set</code> of attributes.
 259    *
 260    * @return The end index of the run.
 261    */
 262   int getRunLimit (Set attribs);
 263
 264   /**
 265    * Returns the index of the character after the end of the run
 266    * that contains the specified attribute defined for the current character.
 267    *
 268    * @param attrib The attribute.
 269    *
 270    * @return The end index of the run.
 271    */
 272   int getRunLimit (AttributedCharacterIterator.Attribute attrib);
 273
 274 } // interface AttributedCharacterIterator