001    /* ===========================================================
002     * JFreeChart : a free chart library for the Java(tm) platform
003     * ===========================================================
004     *
005     * (C) Copyright 2000-2005, by Object Refinery Limited and Contributors.
006     *
007     * Project Info:  http://www.jfree.org/jfreechart/index.html
008     *
009     * This library is free software; you can redistribute it and/or modify it 
010     * under the terms of the GNU Lesser General Public License as published by 
011     * the Free Software Foundation; either version 2.1 of the License, or 
012     * (at your option) any later version.
013     *
014     * This library is distributed in the hope that it will be useful, but 
015     * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 
016     * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public 
017     * License for more details.
018     *
019     * You should have received a copy of the GNU Lesser General Public
020     * License along with this library; if not, write to the Free Software
021     * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, 
022     * USA.  
023     *
024     * [Java is a trademark or registered trademark of Sun Microsystems, Inc. 
025     * in the United States and other countries.]
026     *
027     * ----------
028     * Block.java
029     * ----------
030     * (C) Copyright 2004, 2005, by Object Refinery Limited.
031     *
032     * Original Author:  David Gilbert (for Object Refinery Limited);
033     * Contributor(s):   -;
034     *
035     * $Id: Block.java,v 1.4.2.1 2005/10/25 20:39:38 mungady Exp $
036     *
037     * Changes:
038     * --------
039     * 22-Oct-2004 : Version 1 (DG);
040     * 08-Feb-2005 : Added ID (DG);
041     * 20-Apr-2005 : Added a new draw() method that can accept params
042     *               and return results (DG);
043     *
044     */
045    
046    package org.jfree.chart.block;
047    
048    import java.awt.Graphics2D;
049    import java.awt.geom.Rectangle2D;
050    
051    import org.jfree.ui.Drawable;
052    import org.jfree.ui.Size2D;
053    
054    /**
055     * A block is an arbitrary item that can be drawn (in Java2D space) within a 
056     * rectangular area, has a preferred size, and can be arranged by an 
057     * {@link Arrangement} manager.
058     */
059    public interface Block extends Drawable {
060        
061        /**
062         * Returns an ID for the block.
063         * 
064         * @return An ID.
065         */
066        public String getID();
067        
068        /**
069         * Sets the ID for the block.
070         * 
071         * @param id  the ID.
072         */
073        public void setID(String id);
074        
075        /**
076         * Arranges the contents of the block, with no constraints, and returns
077         * the block size.
078         * 
079         * @param g2  the graphics device.
080         * 
081         * @return The size of the block.
082         */
083        public Size2D arrange(Graphics2D g2);  
084        
085        /**
086         * Arranges the contents of the block, within the given constraints, and 
087         * returns the block size.
088         * 
089         * @param g2  the graphics device.
090         * @param constraint  the constraint (<code>null</code> not permitted).
091         * 
092         * @return The block size (in Java2D units, never <code>null</code>).
093         */
094        public Size2D arrange(Graphics2D g2, RectangleConstraint constraint);
095        
096        /**
097         * Returns the current bounds of the block.
098         * 
099         * @return The bounds.
100         */
101        public Rectangle2D getBounds();
102        
103        /**
104         * Sets the bounds of the block.
105         * 
106         * @param bounds  the bounds.
107         */
108        public void setBounds(Rectangle2D bounds);
109        
110        /**
111         * Draws the block within the specified area.  Refer to the documentation 
112         * for the implementing class for information about the <code>params</code>
113         * and return value supported.
114         * 
115         * @param g2  the graphics device.
116         * @param area  the area.
117         * @param params  optional parameters (<code>null</code> permitted).
118         * 
119         * @return An optional return value (possibly <code>null</code>).
120         */
121        public Object draw(Graphics2D g2, Rectangle2D area, Object params);   
122    
123    }