toolchain/gcc/libjava/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., 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.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
  52   extends AbstractBorder
  53 {
  54   /**
  55    * Determined using the <code>serialver</code> tool
  56    * of Apple/Sun JDK 1.3.1 on MacOS X 10.1.5.
  57    */
  58   static final long serialVersionUID = 9054540377030555103L;
  59
  60
  61   /**
  62    * The inside border, which is painted between the bordered
  63    * Component and the outside border. It is valid for
  64    * <code>insideBorder</code> to be <code>null</code>.
  65    */
  66   protected Border insideBorder;
  67
  68
  69   /**
  70    * The outside border, which is painted outside both the
  71    * bordered Component and the inside border. It is valid for
  72    * <code>outsideBorder</code> to be <code>null</code>.
  73    */
  74   protected Border outsideBorder;
  75
  76
  77   /**
  78    * Constructs a CompoundBorder whose inside and outside borders
  79    * are both <code>null</code>. While this does not really make
  80    * any sense (there exists a class EmptyBorder as well, and not
  81    * every Component needs to have a border at all), the API
  82    * specification requires the existence of this constructor.
  83    *
  84    * @see EmptyBorder
  85    */
  86   public CompoundBorder ()
  87   {
  88     this (null, null);
  89   }
  90
  91
  92   /**
  93    * Constructs a CompoundBorder with the specified inside and
  94    * outside borders.
  95    *
  96    * @param outsideBorder the outside border, which is painted to the
  97    *        outside of both <code>insideBorder</code> and the enclosed
  98    *        component. It is acceptable to pass <code>null</code>, in
  99    *        which case no outside border is painted.
 100    *
 101    * @param insideBorder the inside border, which is painted to
 102    *        between <code>outsideBorder</code> and the enclosed
 103    *        component. It is acceptable to pass <code>null</code>, in
 104    *        which case no inside border is painted.
 105    */
 106   public CompoundBorder (Border outsideBorder, Border insideBorder)
 107   {
 108     this.outsideBorder = outsideBorder;
 109     this.insideBorder = insideBorder;
 110   }
 111
 112
 113   /**
 114    * Determines whether or not this border is opaque. An opaque
 115    * border fills every pixel in its area when painting. Partially
 116    * translucent borders must return <code>false</code>, or ugly
 117    * artifacts can appear on screen.
 118    *
 119    * @return <code>true</code> if both the inside and outside borders
 120    *         are opaque, or <code>false</code> otherwise.
 121    */
 122   public boolean isBorderOpaque ()
 123   {
 124     /* While it would be safe to assume true for the opacity of
 125      * a null border, this behavior would not be according to
 126      * the API specification. Also, it is pathological to have
 127      * null borders anyway.
 128      */
 129     if ((insideBorder == null) || (outsideBorder == null))
 130       return false;
 131
 132     return insideBorder.isBorderOpaque()
 133       && outsideBorder.isBorderOpaque();
 134   }
 135
 136
 137   /**
 138    * Paints the compound border by first painting the outside border,
 139    * then painting the inside border tightly nested into the outside.
 140    *
 141    * @param c the component whose border is to be painted.
 142    * @param g the graphics for painting.
 143    * @param x the horizontal position for painting the border.
 144    * @param y the vertical position for painting the border.
 145    * @param width the width of the available area for painting the border.
 146    * @param height the height of the available area for painting the border.
 147    */
 148   public void paintBorder(Component c, Graphics g,
 149                           int x, int y, int width, int height)
 150   {
 151     /* If there is an outside border, paint it and reduce the
 152      * bounding box by its insets.
 153      */
 154     if (outsideBorder != null)
 155     {
 156       Insets outsideInsets;
 157
 158       outsideBorder.paintBorder(c, g, x, y, width, height);
 159       outsideInsets = outsideBorder.getBorderInsets(c);
 160
 161       x += outsideInsets.left;
 162       y += outsideInsets.top;
 163
 164       /* Reduce width and height by the respective extent of the
 165        * outside border.
 166        */
 167       width -= outsideInsets.left + outsideInsets.right;
 168       height -= outsideInsets.top + outsideInsets.bottom;
 169     }
 170
 171     if (insideBorder != null)
 172       insideBorder.paintBorder(c, g, x, y, width, height);
 173   }
 174
 175
 176   /**
 177    * Changes the specified insets to the insets of this border,
 178    * which is the sum of the insets of the inside and the outside
 179    * border.
 180    *
 181    * @param c the component in the center of this border.
 182    * @param insets an Insets object for holding the added insets.
 183    *
 184    * @return the <code>insets</code> object.
 185    */
 186   public Insets getBorderInsets(Component c, Insets insets)
 187   {
 188     Insets borderInsets;
 189
 190     if (insets == null)
 191       insets = new Insets (0,0,0,0);
 192     else
 193       insets.left = insets.right = insets.top = insets.bottom = 0;
 194
 195     /* If there is an outside border, add it to insets. */
 196     if (outsideBorder != null)
 197     {
 198       borderInsets = outsideBorder.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     /* If there is an inside border, add it to insets. */
 206     if (insideBorder != null)
 207     {
 208       borderInsets = insideBorder.getBorderInsets(c);
 209       insets.left += borderInsets.left;
 210       insets.right += borderInsets.right;
 211       insets.top += borderInsets.top;
 212       insets.bottom += borderInsets.bottom;
 213     }
 214
 215     return insets;
 216   }
 217
 218
 219   /**
 220    * Determines the insets of this border, which is the sum of the
 221    * insets of the inside and the outside border.
 222    *
 223    * @param c the component in the center of this border.
 224    */
 225   public Insets getBorderInsets (Component c)
 226   {
 227     /* It is not clear why CompoundBorder does not simply inherit
 228      * the implementation from AbstractBorder. However, we want
 229      * to be compatible with the API specification, which overrides
 230      * the getBorderInsets(Component) method.
 231      */
 232     return getBorderInsets (c, null);
 233   }
 234
 235
 236   /**
 237    * Returns the outside border, which is painted outside both the
 238    * bordered Component and the inside border. It is valid for the
 239    * result to be <code>null</code>.
 240    */
 241   public Border getOutsideBorder ()
 242   {
 243     return outsideBorder;
 244   }
 245
 246
 247   /**
 248    * Returns the inside border, which is painted between the bordered
 249    * Component and the outside border. It is valid for the result to
 250    * be <code>null</code>.
 251    */
 252   public Border getInsideBorder ()
 253   {
 254     return insideBorder;
 255   }
 256 }
 257