FULL PRODUCT VERSION :
java version "1.6.0-rc"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.6.0-rc-b61)
Java HotSpot(TM) Client VM (build 1.6.0-rc-b61, mixed mode, sharing)

ADDITIONAL OS VERSION INFORMATION :
Microsoft Windows XP [version 5.1.2600]

A DESCRIPTION OF THE PROBLEM :
Since java 1.2 (i think), all methods getGraphics() return
a Graphics2D.
Image.getGraphics() only returns a Graphics because of
backward compatibility.

The SplashScreen API is included since mustang,
so there is no such compatibility requirement,
SpashScreen.getGraphics() should returns a Graphics2D.

And permits to avoid an ugly cast in all users code.

Proposed fix :
public Graphics2D getGraphics() throws IllegalStateException {
        if (image==null) {
            Dimension dim = getSize();
            image = new BufferedImage(dim.width, dim.height, BufferedImage.TYPE_INT_ARGB);
        }
        return image.createGraphics();
    }

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
call getGraphics() on a splash screen instance.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
Graphics2D g=splash.getGraphics();
g.setPaint(new GradientPaint(...));

ACTUAL -
Graphics2D g=(Graphics2D)splash.getGraphics();
g.setPaint(new GradientPaint(...));

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
import java.awt.Color;
import java.awt.Dimension;
import java.awt.GradientPaint;
import java.awt.Graphics2D;
import java.awt.Rectangle;
import java.awt.SplashScreen;

public class BugTest {
  public static void main(String[] args) throws InterruptedException {
    final SplashScreen splash=SplashScreen.getSplashScreen();
    Graphics2D graphics=(Graphics2D)splash.getGraphics();
    Dimension size=splash.getSize();
    graphics.setPaint(new GradientPaint(0,0,Color.BLUE,size.width,size.height,Color.BLACK));
    for(int i=0;i<5;i++) {
      graphics.fill(new Rectangle(20+i*70,size.height-70,50,50));
      splash.update();
      Thread.sleep(500);
    }
    
    graphics.dispose();
    splash.close();
  }
}
---------- END SOURCE ----------