Source for org.jfree.chart.block.EmptyBlock

   1: /* ===========================================================
   2:  * JFreeChart : a free chart library for the Java(tm) platform
   3:  * ===========================================================
   4:  *
   5:  * (C) Copyright 2000-2008, by Object Refinery Limited and Contributors.
   6:  *
   7:  * Project Info:  http://www.jfree.org/jfreechart/index.html
   8:  *
   9:  * This library is free software; you can redistribute it and/or modify it
  10:  * under the terms of the GNU Lesser General Public License as published by
  11:  * the Free Software Foundation; either version 2.1 of the License, or
  12:  * (at your option) any later version.
  13:  *
  14:  * This library is distributed in the hope that it will be useful, but
  15:  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  16:  * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
  17:  * License for more details.
  18:  *
  19:  * You should have received a copy of the GNU Lesser General Public
  20:  * License along with this library; if not, write to the Free Software
  21:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
  22:  * USA.
  23:  *
  24:  * [Java is a trademark or registered trademark of Sun Microsystems, Inc.
  25:  * in the United States and other countries.]
  26:  *
  27:  * ---------------
  28:  * EmptyBlock.java
  29:  * ---------------
  30:  * (C) Copyright 2004-2008, by Object Refinery Limited.
  31:  *
  32:  * Original Author:  David Gilbert (for Object Refinery Limited);
  33:  * Contributor(s):   -;
  34:  *
  35:  * Changes:
  36:  * --------
  37:  * 22-Oct-2004 : Version 1 (DG);
  38:  * 04-Feb-2005 : Now cloneable and serializable (DG);
  39:  * 20-Apr-2005 : Added new draw() method (DG);
  40:  * 08-Apr-2008 : Added support for margin and border (DG);
  41:  * 08-May-2008 : Updated arrange() method to recognise
  42:  *               incoming constraint (DG);
  43:  *
  44:  */
  45: 
  46: package org.jfree.chart.block;
  47: 
  48: import java.awt.Graphics2D;
  49: import java.awt.geom.Rectangle2D;
  50: import java.io.Serializable;
  51: 
  52: import org.jfree.ui.Size2D;
  53: import org.jfree.util.PublicCloneable;
  54: 
  55: /**
  56:  * An empty block with a fixed size.
  57:  */
  58: public class EmptyBlock extends AbstractBlock
  59:         implements Block, Cloneable, PublicCloneable, Serializable {
  60: 
  61:     /** For serialization. */
  62:     private static final long serialVersionUID = -4083197869412648579L;
  63: 
  64:     /**
  65:      * Creates a new block with the specified width and height.
  66:      *
  67:      * @param width  the width.
  68:      * @param height  the height.
  69:      */
  70:     public EmptyBlock(double width, double height) {
  71:         setWidth(width);
  72:         setHeight(height);
  73:     }
  74: 
  75:     /**
  76:      * Arranges the contents of the block, within the given constraints, and
  77:      * returns the block size.
  78:      *
  79:      * @param g2  the graphics device.
  80:      * @param constraint  the constraint (<code>null</code> not permitted).
  81:      *
  82:      * @return The block size (in Java2D units, never <code>null</code>).
  83:      */
  84:     public Size2D arrange(Graphics2D g2, RectangleConstraint constraint) {
  85:         Size2D base = new Size2D(calculateTotalWidth(getWidth()),
  86:                 calculateTotalHeight(getHeight()));
  87:         return constraint.calculateConstrainedSize(base);
  88: }
  89: 
  90:     /**
  91:      * Draws the block.  Since the block is empty, there is nothing to draw
  92:      * except the optional border.
  93:      *
  94:      * @param g2  the graphics device.
  95:      * @param area  the area.
  96:      */
  97:     public void draw(Graphics2D g2, Rectangle2D area) {
  98:         draw(g2, area, null);
  99:     }
 100: 
 101:     /**
 102:      * Draws the block within the specified area.  Since the block is empty,
 103:      * there is nothing to draw except the optional border.
 104:      *
 105:      * @param g2  the graphics device.
 106:      * @param area  the area.
 107:      * @param params  ignored (<code>null</code> permitted).
 108:      *
 109:      * @return Always <code>null</code>.
 110:      */
 111:     public Object draw(Graphics2D g2, Rectangle2D area, Object params) {
 112:         area = trimMargin(area);
 113:         drawBorder(g2, area);
 114:         return null;
 115:     }
 116: 
 117:     /**
 118:      * Returns a clone of the block.
 119:      *
 120:      * @return A clone.
 121:      *
 122:      * @throws CloneNotSupportedException if there is a problem cloning.
 123:      */
 124:     public Object clone() throws CloneNotSupportedException {
 125:         return super.clone();
 126:     }
 127: 
 128: }