libjava/javax/swing/border/MatteBorder.java

   1 /* MatteBorder.java --
   2    Copyright (C) 2003, 2004  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.Color;
  42 import java.awt.Component;
  43 import java.awt.Graphics;
  44 import java.awt.Insets;
  45
  46 import javax.swing.Icon;
  47
  48 /**
  49  * A border that is filled with either a solid color or with repeated
  50  * icon tiles.
  51  *
  52  * <p><img src="doc-files/MatteBorder-1.png" width="500" height="150"
  53  * alt="[Two MatteBorders]" />
  54  *
  55  * @author Sascha Brawer (brawer@dandelis.ch)
  56  */
  57 public class MatteBorder
  58   extends EmptyBorder
  59 {
  60   /**
  61    * Determined using the <code>serialver</code> tool
  62    * of Apple/Sun JDK 1.3.1 on MacOS X 10.1.5.
  63    */
  64   static final long serialVersionUID = 4422248989617298224L;
  65
  66
  67   /**
  68    * The color that is used for filling the border, or
  69    * <code>null</code> if the border is filled with repetitions of a
  70    * tile icon.
  71    *
  72    * @see #tileIcon
  73    */
  74   protected Color color;
  75
  76
  77   /**
  78    * The icon is used for filling the border with a tile, or
  79    * <code>null</code> if the border is filled with a solid
  80    * color.
  81    *
  82    * @see #color
  83    */
  84   protected Icon tileIcon;
  85
  86
  87   /**
  88    * Constructs a MatteBorder given the width on each side
  89    * and a fill color.
  90    *
  91    * <p><img src="doc-files/MatteBorder-2.png" width="500" height="150"
  92    * alt="[A picture of a MatteBorder made by this constructor]" />
  93    *
  94    * @param top the width of the border at its top edge.
  95    * @param left the width of the border at its left edge.
  96    * @param bottom the width of the border at its bottom edge.
  97    * @param right the width of the border at its right edge.
  98    * @param matteColor the color for filling the border.
  99    */
 100   public MatteBorder(int top, int left, int bottom, int right,
 101                      Color matteColor)
 102   {
 103     super(top, left, bottom, right);
 104
 105     if (matteColor == null)
 106       throw new IllegalArgumentException();
 107
 108     this.color = matteColor;
 109   }
 110
 111
 112   /**
 113    * Constructs a MatteBorder given its insets and fill color.
 114    *
 115    * <p><img src="doc-files/MatteBorder-3.png" width="500" height="150"
 116    * alt="[A picture of a MatteBorder made by this constructor]" />
 117    *
 118    * @param borderInsets an Insets object whose <code>top</code>,
 119    *        <code>left</code>, <code>bottom</code> and <code>right</code>
 120    *        fields indicate the with of the border at the respective
 121    *        edge.
 122    *
 123    * @param matteColor the color for filling the border.
 124    */
 125   public MatteBorder(Insets borderInsets, Color matteColor)
 126   {
 127     this(borderInsets.top, borderInsets.left,
 128          borderInsets.bottom, borderInsets.right,
 129          matteColor);
 130   }
 131
 132
 133   /**
 134    * Constructs a MatteBorder given the width on each side
 135    * and an icon for tiling the border area.
 136    *
 137    * <p><img src="doc-files/MatteBorder-4.png" width="500" height="150"
 138    * alt="[A picture of a MatteBorder made by this constructor]" />
 139    *
 140    * @param top the width of the border at its top edge.
 141    * @param left the width of the border at its left edge.
 142    * @param bottom the width of the border at its bottom edge.
 143    * @param right the width of the border at its right edge.
 144    * @param tileIcon an icon for tiling the border area.
 145    */
 146   public MatteBorder(int top, int left, int bottom, int right,
 147                      Icon tileIcon)
 148   {
 149     super(top, left, bottom, right);
 150
 151     if (tileIcon == null)
 152       throw new IllegalArgumentException();
 153
 154     this.tileIcon = tileIcon;
 155   }
 156
 157
 158   /**
 159    * Constructs a MatteBorder given its insets and an icon
 160    * for tiling the border area.
 161    *
 162    * <p><img src="doc-files/MatteBorder-5.png" width="500" height="150"
 163    * alt="[A picture of a MatteBorder made by this constructor]" />
 164    *
 165    * @param borderInsets an Insets object whose <code>top</code>,
 166    *        <code>left</code>, <code>bottom</code> and <code>right</code>
 167    *        fields indicate the with of the border at the respective
 168    *        edge.
 169    *
 170    * @param tileIcon an icon for tiling the border area.
 171    */
 172   public MatteBorder(Insets borderInsets, Icon tileIcon)
 173   {
 174     this(borderInsets.top, borderInsets.left,
 175          borderInsets.bottom, borderInsets.right,
 176          tileIcon);
 177   }
 178
 179
 180   /**
 181    * Constructs a MatteBorder given an icon for tiling the
 182    * border area. The icon width is used for the border insets
 183    * at the left and right edge, the icon height for the top and
 184    * bottom edge.
 185    *
 186    * <p><img src="doc-files/MatteBorder-6.png" width="379" height="150"
 187    * alt="[A picture of a MatteBorder made by this constructor]" />
 188    *
 189    * @param tileIcon an icon for tiling the border area.
 190    */
 191   public MatteBorder(Icon tileIcon)
 192   {
 193     this(-1, -1, -1, -1, tileIcon);
 194   }
 195
 196
 197   /**
 198    * Paints the border for a given component.
 199    *
 200    * @param c the component whose border is to be painted.
 201    * @param g the graphics for painting.
 202    * @param x the horizontal position for painting the border.
 203    * @param y the vertical position for painting the border.
 204    * @param width the width of the available area for painting the border.
 205    * @param height the height of the available area for painting the border.
 206    */
 207   public void paintBorder(Component c, Graphics  g,
 208                           int x, int y, int width, int height)
 209   {
 210     Insets i = getBorderInsets();
 211     paintEdge(c, g, x, y, width, i.top, 0, 0);      // top edge
 212     paintEdge(c, g, x, y + height - i.bottom,       // bottom edge
 213               width, i.bottom,
 214               0, height - i.bottom);
 215     paintEdge(c, g, x, y + i.top,                   // left edge
 216               i.left, height - i.top,
 217               0, i.top);
 218     paintEdge(c, g, x + width - i.right, y + i.top, // right edge
 219               i.right, height - i.bottom,
 220               width - i.right, i.top);
 221   }
 222
 223
 224   /**
 225    * Measures the width of this border.
 226    *
 227    * @param c the component whose border is to be measured.
 228    *
 229    * @return an Insets object whose <code>left</code>, <code>right</code>,
 230    *         <code>top</code> and <code>bottom</code> fields indicate the
 231    *         width of the border at the respective edge.
 232    *
 233    * @see #getBorderInsets(java.awt.Component, java.awt.Insets)
 234    */
 235   public Insets getBorderInsets(Component c)
 236   {
 237     /* There is no obvious reason for overriding this method, but we
 238      * try to have exactly the same API as the Sun reference
 239      * implementation.
 240      */
 241     return this.getBorderInsets(c, null);
 242   }
 243
 244
 245   /**
 246    * Measures the width of this border, storing the results into a
 247    * pre-existing Insets object.
 248    *
 249    * @param insets an Insets object for holding the result values.
 250    *        After invoking this method, the <code>left</code>,
 251    *        <code>right</code>, <code>top</code> and
 252    *        <code>bottom</code> fields indicate the width of the
 253    *        border at the respective edge.
 254    *
 255    * @return the same object that was passed for <code>insets</code>.
 256    *
 257    * @see #getBorderInsets()
 258    */
 259   public Insets getBorderInsets(Component c, Insets insets)
 260   {
 261     if (insets == null)
 262       insets = new Insets(0, 0, 0, 0);
 263
 264     if ((tileIcon != null)
 265         && (top < 0) && (left < 0)
 266         && (right < 0) && (bottom < 0))
 267     {
 268       insets.left = insets.right = tileIcon.getIconWidth();
 269       insets.top = insets.bottom = tileIcon.getIconHeight();
 270       return insets;
 271     }
 272
 273     /* Copy top, left, bottom and right into the respective
 274      * field of insets.
 275      */
 276     return super.getBorderInsets(c, insets);
 277   }
 278
 279
 280   /**
 281    * Measures the width of this border.
 282    *
 283    * @return an Insets object whose <code>left</code>, <code>right</code>,
 284    *         <code>top</code> and <code>bottom</code> fields indicate the
 285    *         width of the border at the respective edge.
 286    *
 287    * @see #getBorderInsets(java.awt.Component, java.awt.Insets)
 288    */
 289   public Insets getBorderInsets()
 290   {
 291     /* The inherited implementation of EmptyBorder.isBorderOpaque()
 292      * would do the same. It is not clear why this is overriden in the
 293      * Sun implementation, at least not from just reading the JavaDoc.
 294      */
 295     return this.getBorderInsets(null, null);
 296   }
 297
 298
 299   /**
 300    * Returns the color that is used for filling the border, or
 301    * <code>null</code> if the border is filled with repetitions of a
 302    * tile icon.
 303    */
 304   public Color getMatteColor()
 305   {
 306     return color;
 307   }
 308
 309
 310   /**
 311    * Returns the icon is used for tiling the border, or
 312    * <code>null</code> if the border is filled with a color instead of
 313    * an icon.
 314    */
 315   public Icon getTileIcon()
 316   {
 317     return tileIcon;
 318   }
 319
 320
 321   /**
 322    * Determines whether this border fills every pixel in its area
 323    * when painting.
 324    *
 325    * @return <code>true</code> if the border is filled with an
 326    *         opaque color; <code>false</code> if it is filled with
 327    *         a semi-transparent color or with an icon.
 328    */
 329   public boolean isBorderOpaque()
 330   {
 331     return (color != null) && (color.getAlpha() == 255);
 332   }
 333
 334
 335   /**
 336    * Paints a rectangular area of the border. This private helper
 337    * method is called once for each of the border edges
 338    * by {@link #paintBorder}.
 339    *
 340    * @param c the component whose border is being painted.
 341    * @param g the graphics for painting.
 342    * @param x the horizontal position of the rectangular area.
 343    * @param y the vertical position of the rectangular area.
 344    * @param width the width of the rectangular area.
 345    * @param height the height of the rectangular area.
 346    * @param dx the x displacement for repeating the tile.
 347    * @param dy the y displacement for repeating the tile.
 348    */
 349   private void paintEdge(Component c, Graphics g,
 350                          int x, int y, int width, int height,
 351                          int dx, int dy)
 352   {
 353     Color oldColor;
 354     int iconWidth, iconHeight;
 355     Graphics clipped;
 356
 357     if ((width <= 0) || (height <= 0))
 358       return;
 359
 360     /* Paint a colored rectangle if desired. */
 361     if (color != null)
 362     {
 363       oldColor = g.getColor();
 364       try
 365       {
 366         g.setColor(color);
 367         g.fillRect(x, y, width, height);
 368       }
 369       finally
 370       {
 371         g.setColor(oldColor);
 372       }
 373       return;
 374     }
 375
 376     /* Determine the width and height of the icon. Some icons return
 377      * -1 if it is an image whose dimensions have not yet been
 378      * retrieved. There is not much we can do about this, but we
 379      * should at least avoid entering the paint loop below
 380      * with negative increments.
 381      */
 382     iconWidth = tileIcon.getIconWidth();
 383     iconHeight = tileIcon.getIconHeight();
 384     if ((iconWidth <= 0) || (iconHeight <= 0))
 385       return;
 386
 387     dx = dx % iconWidth;
 388     dy = dy % iconHeight;
 389
 390     clipped = g.create();
 391     try
 392     {
 393       clipped.setClip(x, y, width, height);
 394       for (int ty = y - dy; ty < y + height; ty += iconHeight)
 395         for (int tx = x - dx; tx < x + width; tx += iconWidth)
 396           tileIcon.paintIcon(c, clipped, tx, ty);
 397     }
 398     finally
 399     {
 400       clipped.dispose();
 401     }
 402   }
 403 }
 404