old-autovect-branch/libjava/classpath/javax/swing/border/CompoundBorder.java

   1 /* CompoundBorder.java --
   2    Copyright (C) 2003 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 javax.swing.border;
  40
  41 import java.awt.Component;
  42 import java.awt.Graphics;
  43 import java.awt.Insets;
  44
  45 /**
  46  * A Border that is composed of an interior and an exterior border,
  47  * where the interior border is tightly nested into the exterior.
  48  *
  49  * @author Sascha Brawer (brawer@dandelis.ch)
  50  */
  51 public class CompoundBorder extends AbstractBorder
  52 {
  53   /**
  54    * Determined using the <code>serialver</code> tool
  55    * of Apple/Sun JDK 1.3.1 on MacOS X 10.1.5.
  56    */
  57   static final long serialVersionUID = 9054540377030555103L;
  58
  59   /**
  60    * The inside border, which is painted between the bordered
  61    * Component and the outside border. It is valid for
  62    * <code>insideBorder</code> to be <code>null</code>.
  63    */
  64   protected Border insideBorder;
  65
  66   /**
  67    * The outside border, which is painted outside both the
  68    * bordered Component and the inside border. It is valid for
  69    * <code>outsideBorder</code> to be <code>null</code>.
  70    */
  71   protected Border outsideBorder;
  72
  73   /**
  74    * Constructs a CompoundBorder whose inside and outside borders
  75    * are both <code>null</code>. While this does not really make
  76    * any sense (there exists a class EmptyBorder as well, and not
  77    * every Component needs to have a border at all), the API
  78    * specification requires the existence of this constructor.
  79    *
  80    * @see EmptyBorder
  81    */
  82   public CompoundBorder()
  83   {
  84     this (null, null);
  85   }
  86
  87   /**
  88    * Constructs a CompoundBorder with the specified inside and
  89    * outside borders.
  90    *
  91    * @param outsideBorder the outside border, which is painted to the
  92    *        outside of both <code>insideBorder</code> and the enclosed
  93    *        component. It is acceptable to pass <code>null</code>, in
  94    *        which case no outside border is painted.
  95    *
  96    * @param insideBorder the inside border, which is painted to
  97    *        between <code>outsideBorder</code> and the enclosed
  98    *        component. It is acceptable to pass <code>null</code>, in
  99    *        which case no inside border is painted.
 100    */
 101   public CompoundBorder(Border outsideBorder, Border insideBorder)
 102   {
 103     this.outsideBorder = outsideBorder;
 104     this.insideBorder = insideBorder;
 105   }
 106
 107   /**
 108    * Determines whether or not this border is opaque. An opaque
 109    * border fills every pixel in its area when painting. Partially
 110    * translucent borders must return <code>false</code>, or ugly
 111    * artifacts can appear on screen.
 112    *
 113    * @return <code>true</code> if both the inside and outside borders
 114    *         are opaque, or <code>false</code> otherwise.
 115    */
 116   public boolean isBorderOpaque()
 117   {
 118     // While it would be safe to assume true for the opacity of
 119     // a null border, this behavior would not be according to
 120     // the API specification. Also, it is pathological to have
 121     // null borders anyway.
 122     if ((insideBorder == null) || (outsideBorder == null))
 123       return false;
 124
 125     return insideBorder.isBorderOpaque()
 126       && outsideBorder.isBorderOpaque();
 127   }
 128
 129   /**
 130    * Paints the compound border by first painting the outside border,
 131    * then painting the inside border tightly nested into the outside.
 132    *
 133    * @param c the component whose border is to be painted.
 134    * @param g the graphics for painting.
 135    * @param x the horizontal position for painting the border.
 136    * @param y the vertical position for painting the border.
 137    * @param width the width of the available area for painting the border.
 138    * @param height the height of the available area for painting the border.
 139    */
 140   public void paintBorder(Component c, Graphics g,
 141                           int x, int y, int width, int height)
 142   {
 143     // If there is an outside border, paint it and reduce the
 144     // bounding box by its insets.
 145     //
 146     if (outsideBorder != null)
 147     {
 148       Insets outsideInsets;
 149
 150       outsideBorder.paintBorder(c, g, x, y, width, height);
 151       outsideInsets = outsideBorder.getBorderInsets(c);
 152
 153       x += outsideInsets.left;
 154       y += outsideInsets.top;
 155
 156       // Reduce width and height by the respective extent of the
 157       // outside border.
 158       width -= outsideInsets.left + outsideInsets.right;
 159       height -= outsideInsets.top + outsideInsets.bottom;
 160     }
 161
 162     if (insideBorder != null)
 163       insideBorder.paintBorder(c, g, x, y, width, height);
 164   }
 165
 166   /**
 167    * Changes the specified insets to the insets of this border,
 168    * which is the sum of the insets of the inside and the outside
 169    * border.
 170    *
 171    * @param c the component in the center of this border.
 172    * @param insets an Insets object for holding the added insets.
 173    *
 174    * @return the <code>insets</code> object.
 175    */
 176   public Insets getBorderInsets(Component c, Insets insets)
 177   {
 178     Insets borderInsets;
 179
 180     if (insets == null)
 181       insets = new Insets (0,0,0,0);
 182     else
 183       insets.left = insets.right = insets.top = insets.bottom = 0;
 184
 185     // If there is an outside border, add it to insets.
 186     if (outsideBorder != null)
 187     {
 188       borderInsets = outsideBorder.getBorderInsets(c);
 189       insets.left += borderInsets.left;
 190       insets.right += borderInsets.right;
 191       insets.top += borderInsets.top;
 192       insets.bottom += borderInsets.bottom;
 193     }
 194
 195     // If there is an inside border, add it to insets.
 196     if (insideBorder != null)
 197     {
 198       borderInsets = insideBorder.getBorderInsets(c);
 199       insets.left += borderInsets.left;
 200       insets.right += borderInsets.right;
 201       insets.top += borderInsets.top;
 202       insets.bottom += borderInsets.bottom;
 203     }
 204
 205     return insets;
 206   }
 207
 208   /**
 209    * Determines the insets of this border, which is the sum of the
 210    * insets of the inside and the outside border.
 211    *
 212    * @param c the component in the center of this border.
 213    */
 214   public Insets getBorderInsets(Component c)
 215   {
 216     // It is not clear why CompoundBorder does not simply inherit
 217     // the implementation from AbstractBorder. However, we want
 218     // to be compatible with the API specification, which overrides
 219     // the getBorderInsets(Component) method.
 220     return getBorderInsets (c, null);
 221   }
 222
 223   /**
 224    * Returns the outside border, which is painted outside both the
 225    * bordered Component and the inside border. It is valid for the
 226    * result to be <code>null</code>.
 227    */
 228   public Border getOutsideBorder()
 229   {
 230     return outsideBorder;
 231   }
 232
 233   /**
 234    * Returns the inside border, which is painted between the bordered
 235    * Component and the outside border. It is valid for the result to
 236    * be <code>null</code>.
 237    */
 238   public Border getInsideBorder ()
 239   {
 240     return insideBorder;
 241   }
 242 }