001/* NavigationFilter.java --
002   Copyright (C) 2003, 2004 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 javax.swing.text;
040
041public class NavigationFilter
042{
043  public abstract static class FilterBypass
044  {
045    public FilterBypass()
046    {
047      // Do nothing here.
048    }
049
050    public abstract Caret getCaret();
051    public abstract void moveDot(int dot, Position.Bias bias);
052    public abstract void setDot(int dot, Position.Bias bias);
053  }
054
055  public NavigationFilter()
056  {
057    // Do nothing here.
058  }
059
060  public void moveDot(NavigationFilter.FilterBypass fb, int dot,
061                      Position.Bias bias)
062  {
063    fb.moveDot(dot, bias);
064  }
065
066  public void setDot(NavigationFilter.FilterBypass fb, int dot,
067                     Position.Bias bias)
068  {
069    fb.setDot(dot, bias);
070  }
071
072  /**
073   * Returns the next visual position in the specified direction at which one
074   * would place a caret. The default implementation forwards to the text
075   * component's root view. Subclasses may wish to restrict that more.
076   *
077   * @param c the text component
078   * @param pos the current model position
079   * @param bias the bias of <code>pos</code>
080   * @param dir the direction, one of {@link javax.swing.SwingConstants#NORTH},
081   *        {@link javax.swing.SwingConstants#SOUTH},
082   *        {@link javax.swing.SwingConstants#WEST} or
083   *        {@link javax.swing.SwingConstants#EAST}
084   * @param retBias the bias of the returned position
085   *
086   * @return the next model location to place the caret
087   *
088   * @throws BadLocationException when <code>pos</code> is not a valid model
089   *         position
090   */
091  public int getNextVisualPositionFrom(JTextComponent c, int pos,
092                                       Position.Bias bias, int dir,
093                                       Position.Bias[] retBias)
094    throws BadLocationException
095  {
096    return c.getUI().getNextVisualPositionFrom(c, pos, bias, dir, retBias);
097  }
098}