FULL PRODUCT VERSION :
java version "1.5.0_06"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.5.0_06-b05)
Java HotSpot(TM) Client VM (build 1.5.0_06-b05, mixed mode, sharing)
java version "1.5.0_05"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.5.0_05-b05)
Java HotSpot(TM) Client VM (build 1.5.0_05-b05, mixed mode)

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

EXTRA RELEVANT SYSTEM CONFIGURATION :
IBM ThinkPad R51, Intel Pentium IV Mobile (1.7 Ghz)

System:
Graphics Card: ATI Mobility Radeon 9000
  
Driver:
  Vendor: ATI Technologies Inc.
  Version: 6.14.10.6525
  Date: 22.03.2005

A DESCRIPTION OF THE PROBLEM :
On a window of a size at about 1000x800 you can easily see how the painting occures line by line (jre 1.5.0_06). Using jre 1.5.0_05 the drawing of the ui was almost instantly drawn. The effect is visible within all Java-Programs I use.

I have tried my test on a different pc (a normal workstation) and cannot see
any difference between jre1.5.0_05 and jre1.5.0_06. It seems to be an
hardware/driver issue.

I have extended the test and got some more information out of it. First,
normally the drawing of the first window takes longer (about factor 5-10)
than the drawing of subsequent windows. I tried this using jre 1.5.0_05
jre1.6b69 on my notebook. But if I try this using jre1.5.0_06 on my notebook
the result differ. The drawing of windows is much slower and does not
speedup when more windows are opened. Then I tried to turn off ddraw and you
can see the result below.

Results: sun.java2d.noddraw

jre 1.5.0_05
true false
130 90
10 10
20 20
10 20
20 20
20 10
10 20
10 10
20 20
20 20

jre 1.5.0_06
true false
70 350
20 341
20 341
20 330
20 330
20 341
20 341
10 340
10 340
10 351

As you can see turning ddraw off speeds up the drawing significantly.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Take a JFrame and put in a set of components. Maximize the JFrame.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
The gui should be instantly updated.
ACTUAL -
You can see how the gui is drawn linewise.

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
import java.awt.Graphics;

import javax.swing.*;

public class JFramePaintTest extends JFrame {

    private static final long serialVersionUID = 2936895701046330214L;

    public JFramePaintTest() {
        setSize(1024, 768);
    }

    @Override
    public void paint(Graphics g) {
        long current = System.currentTimeMillis();
        super.paint(g);
        System.out.println(System.currentTimeMillis() - current);
        setVisible(false);
    }

    static JFramePaintTest frame;

    public static void main(String[] args) {
        System.setProperty("sun.java2d.noddraw", "true");
        for (int x = 0; x < 10; x++) {
            frame = new JFramePaintTest();
            try {
                SwingUtilities.invokeAndWait(new Runnable() {
                    public void run() {
                        frame.setVisible(true);
                    }
                });
            } catch (Exception e1) {
                // Ignore
            }
            while (frame.isVisible()) {
                try {
                    Thread.sleep(500);
                } catch (InterruptedException e) {
                    // Ignore
                }
            }
        }
        System.exit(0);
    }
}
---------- END SOURCE ----------