/* * Copyright (c) 2000 David Flanagan.  All rights reserved. * This code is from the book Java Examples in a Nutshell, 2nd Edition. * It is provided AS-IS, WITHOUT ANY WARRANTY either expressed or implied. * You may study, use, and modify it for any non-commercial purpose. * You may distribute it non-commercially as long as you retain this notice. * For a commercial use license, or to purchase the book (recommended), * visit http://www.davidflanagan.com/javaexamples2. */package com.davidflanagan.examples.graphics;import java.awt.*;import java.awt.geom.*;import java.awt.image.*;/** * This is a Paint implementation that fills every raster with a random * opaque color.  Using this Paint class allows you to visualize the * painting algorithm used by your Java2D implementation.  **/public class RandomPaint implements Paint {    /** This is the main Paint method;  all it does is return a PaintContext */    public PaintContext createContext(ColorModel cm,				      Rectangle deviceBounds,				      Rectangle2D userBounds,				      AffineTransform xform,				      RenderingHints hints) {	return new RandomPaintContext();    }    /** This Paint object only uses opaque colors */    public int getTransparency() { return OPAQUE; }    /**     * The PaintContext class does all the work of painting     **/    class RandomPaintContext implements PaintContext {	BufferedImage image;              // An image we can draw into	Graphics2D imageGraphics;         // The Graphics object to do it with	java.util.Random randomizer =     // For generating random numbers	    new java.util.Random(System.currentTimeMillis());  // seed value	Rectangle rect = new Rectangle(); // A scratch rectangle	/** Return the color model used by this Paint implementation */	public ColorModel getColorModel() { return image.getColorModel(); }	/**	 * This is the main method of PaintContext.  It must return a Raster	 * that contains fill data for the specified rectangle.  For this 	 * implementation, we just fill with a random solid color each time.	 * Instead of setting pixels at the Raster level, we instead 	 * manipulate a BufferedImage using the Graphics.fillRect() method.	 * Note that we never create an image larger than we need.	 **/	public Raster getRaster(int x, int y, int w, int h) {	    // Create an initial image or a larger image as needed	    if ((image == null) || (image.getWidth() < w) ||		(image.getHeight() < h)) {		image = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);		imageGraphics = image.createGraphics();	    }	    // Choose and use a random color	    imageGraphics.setColor(new Color(randomizer.nextInt(256),					     randomizer.nextInt(256),					     randomizer.nextInt(256)));	    // Fill a rectangle of the specified size with that color	    imageGraphics.fillRect(0, 0, w, h);	    // Then extract the corresponding Raster from the image and return	    rect.x = 0; rect.y = 0; rect.width = w; rect.height = h;	    return image.getData(rect);	}	/** Called when the PaintContext is no longer needed. */	public void dispose() {	    imageGraphics.dispose();  	    image = null;	    imageGraphics = null;	}    }}