libjava/javax/accessibility/AccessibleText.java

   1 /* AccessibleText.java -- aids in accessibly manipulating text
   2    Copyright (C) 2000, 2002 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., 59 Temple Place, Suite 330, Boston, MA
  19 02111-1307 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 javax.accessibility;
  40
  41 import java.awt.Rectangle;
  42 import java.awt.Point;
  43 import javax.swing.text.AttributeSet;
  44
  45 /**
  46  * Objects which present textual information on the display should implement
  47  * this interface.  Accessibility software can use the implementations of
  48  * this interface to change the attributes and spacial location of the text.
  49  *
  50  * <p>The <code>AccessibleContext.getAccessibleText()</code> method
  51  * should return <code>null</code> if an object does not implement this
  52  * interface.
  53  *
  54  * @author Eric Blake <ebb9@email.byu.edu>
  55  * @see Accessible
  56  * @see AccessibleContext
  57  * @see AccessibleContext#getAccessibleText()
  58  * @since 1.2
  59  * @status updated to 1.4
  60  */
  61 public interface AccessibleText
  62 {
  63   /**
  64    * Constant designating that the next selection should be a character.
  65    *
  66    * @see #getAtIndex(int, int)
  67    * @see #getAfterIndex(int, int)
  68    * @see #getBeforeIndex(int, int)
  69    */
  70   int CHARACTER = 1;
  71
  72   /**
  73    * Constant designating that the next selection should be a word.
  74    *
  75    * @see #getAtIndex(int, int)
  76    * @see #getAfterIndex(int, int)
  77    * @see #getBeforeIndex(int, int)
  78    */
  79   int WORD = 2;
  80
  81   /**
  82    * Constant designating that the next selection should be a sentence.
  83    *
  84    * @see #getAtIndex(int, int)
  85    * @see #getAfterIndex(int, int)
  86    * @see #getBeforeIndex(int, int)
  87    */
  88   int SENTENCE = 3;
  89
  90   /**
  91    * Given a point in the coordinate system of this object, return the
  92    * 0-based index of the character at that point, or -1 if there is none.
  93    *
  94    * @param p the point to look at
  95    * @return the character index, or -1
  96    */
  97   int getIndexAtPoint(Point point);
  98
  99   /**
 100    * Determines the bounding box of the indexed character. Returns an empty
 101    * rectangle if the index is out of bounds.
 102    *
 103    * @param index the 0-based character index
 104    * @return the bounding box, may be empty
 105    */
 106   Rectangle getCharacterBounds(int index);
 107
 108   /**
 109    * Return the number of characters.
 110    *
 111    * @return the character count
 112    */
 113   int getCharCount();
 114
 115   /**
 116    * Return the offset of the character. The offset matches the index of the
 117    * character to the right, since the carat lies between characters.
 118    *
 119    * @return the 0-based caret position
 120    */
 121   int getCaretPosition();
 122
 123   /**
 124    * Returns the section of text at the index, or null if the index or part
 125    * is invalid.
 126    *
 127    * @param part {@link CHARACTER}, {@link WORD}, or {@link SENTENCE}
 128    * @param index the 0-based character index
 129    * @return the selection of text at that index, or null
 130    */
 131   String getAtIndex(int part, int index);
 132
 133   /**
 134    * Returns the section of text after the index, or null if the index or part
 135    * is invalid.
 136    *
 137    * @param part {@link CHARACTER}, {@link WORD}, or {@link SENTENCE}
 138    * @param index the 0-based character index
 139    * @return the selection of text after that index, or null
 140    */
 141   String getAfterIndex(int part, int index);
 142
 143   /**
 144    * Returns the section of text before the index, or null if the index or part
 145    * is invalid.
 146    *
 147    * @param part {@link CHARACTER}, {@link WORD}, or {@link SENTENCE}
 148    * @param index the 0-based character index
 149    * @return the selection of text before that index, or null
 150    */
 151   String getBeforeIndex(int part, int index);
 152
 153   /**
 154    * Returns the attributes of a character at an index, or null if the index
 155    * is out of bounds.
 156    *
 157    * @param index the 0-based character index
 158    * @return the character's attributes
 159    */
 160   AttributeSet getCharacterAttribute(int index);
 161
 162   /**
 163    * Returns the start index of the selection. If there is no selection, this
 164    * is the same as the caret location.
 165    *
 166    * @return the 0-based character index of the selection start
 167    */
 168   int getSelectionStart();
 169
 170   /**
 171    * Returns the end index of the selection. If there is no selection, this
 172    * is the same as the caret location.
 173    *
 174    * @return the 0-based character index of the selection end
 175    */
 176   int getSelectionEnd();
 177
 178   /**
 179    * Returns the selected text. This may be null or "" if no text is selected.
 180    *
 181    * @return the selected text
 182    */
 183   String getSelectedText();
 184 } // interface AccessibleText