Java Component.getSize示例

 BufferedImage createImageFromComponent(Component comp) {
   BufferedImage retImage = null;
   if (comp == null) return retImage;
   try {
     GraphicsEnvironment genv = GraphicsEnvironment.getLocalGraphicsEnvironment();
     GraphicsDevice gd = genv.getDefaultScreenDevice();
     GraphicsConfiguration gc = gd.getDefaultConfiguration();
     java.awt.image.ColorModel cm = gc.getColorModel();
     boolean hasAlpha = cm.hasAlpha();
     int cw = comp.getSize().width;
     int ch = comp.getSize().height;
     if (hasAlpha) {
       retImage = gc.createCompatibleImage(cw, ch);
     } else {
       retImage = new BufferedImage(cw, ch, BufferedImage.TYPE_INT_ARGB);
     }
     if (retImage == null) return retImage;
     Graphics og = retImage.getGraphics();
     comp.paint(og);
     og.dispose();
   } catch (Throwable t) {
   }
   return retImage;
 }