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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * particular file as subject to the "Classpath" exception as provided
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 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
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package sun.awt.image;

import java.awt.Component;
import java.awt.Color;
import java.awt.SystemColor;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.GraphicsEnvironment;
import java.awt.image.BufferedImage;
import java.awt.image.ImageProducer;
import java.awt.image.ColorModel;
import java.awt.image.WritableRaster;
import sun.java2d.SunGraphics2D;
import sun.java2d.SurfaceData;

This is a special variant of BufferedImage that keeps a reference to a Component. The Component's foreground and background colors and default font are used as the defaults for this image.
/** * This is a special variant of BufferedImage that keeps a reference to * a Component. The Component's foreground and background colors and * default font are used as the defaults for this image. */
public class OffScreenImage extends BufferedImage { protected Component c; private OffScreenImageSource osis; private Font defaultFont;
Constructs an OffScreenImage given a color model and tile, for offscreen rendering to be used with a given component. The component is used to obtain the foreground color, background color and font.
/** * Constructs an OffScreenImage given a color model and tile, * for offscreen rendering to be used with a given component. * The component is used to obtain the foreground color, background * color and font. */
public OffScreenImage(Component c, ColorModel cm, WritableRaster raster, boolean isRasterPremultiplied) { super(cm, raster, isRasterPremultiplied, null); this.c = c; initSurface(raster.getWidth(), raster.getHeight()); } public Graphics getGraphics() { return createGraphics(); } public Graphics2D createGraphics() { if (c == null) { GraphicsEnvironment env = GraphicsEnvironment.getLocalGraphicsEnvironment(); return env.createGraphics(this); } Color bg = c.getBackground(); if (bg == null) { bg = SystemColor.window; } Color fg = c.getForeground(); if (fg == null) { fg = SystemColor.windowText; } Font font = c.getFont(); if (font == null) { if (defaultFont == null) { defaultFont = new Font("Dialog", Font.PLAIN, 12); } font = defaultFont; } return new SunGraphics2D(SurfaceData.getPrimarySurfaceData(this), fg, bg, font); } private void initSurface(int width, int height) { Graphics2D g2 = createGraphics(); try { g2.clearRect(0, 0, width, height); } finally { g2.dispose(); } } public ImageProducer getSource() { if (osis == null) { osis = new OffScreenImageSource(this); } return osis; } }