001    /* AccessibleAction.java -- aids in accessibly performing actions
002       Copyright (C) 2000, 2002, 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    
039    package javax.accessibility;
040    
041    /**
042     * If an object implements this interface then it must be able to perform one
043     * or more actions. Accessibility software can use the implementations of this
044     * interface to discover and perform actions on an object.
045     *
046     * <p>The <code>AccessibleContext.getAccessibleAction()</code> method should
047     * return <code>null</code> if an object does not implement this interface.
048     *
049     * @author Eric Blake (ebb9@email.byu.edu)
050     * @see Accessible
051     * @see AccessibleContext
052     * @see AccessibleContext#getAccessibleAction()
053     * @since 1.2
054     * @status updated to 1.4
055     */
056    public interface AccessibleAction
057    {
058    
059      /**
060       * The name of an action which decrements a value.
061       *
062       * @since 1.5
063       */
064      static final String DECREMENT = "decrement";
065    
066      /**
067       * The name of an action which increments a value.
068       *
069       * @since 1.5
070       */
071      static final String INCREMENT = "increment";
072    
073      /**
074       * The name of an action which toggles the expansion of a tree node.
075       *
076       * @since 1.5
077       */
078      static final String TOGGLE_EXPAND = "toggle expand";
079    
080      /**
081       * Get the number possible actions for this object, with the zeroth
082       * representing the default action.
083       *
084       * @return the 0-based number of actions
085       */
086      int getAccessibleActionCount();
087    
088      /**
089       * Get a description for the specified action. Returns null if out of
090       * bounds.
091       *
092       * @param i the action to describe, 0-based
093       * @return description of the action
094       */
095      String getAccessibleActionDescription(int i);
096    
097      /**
098       * Perform the specified action. Does nothing if out of bounds.
099       *
100       * @param i the action to perform, 0-based
101       * @return true if the action was performed
102       */
103      boolean doAccessibleAction(int i);
104    } // interface AccessibleAction