Name: rmT116609 Date: 08/11/2004


FULL PRODUCT VERSION :
java version "1.5.0-beta2"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.5.0-beta2-b51)
Java HotSpot(TM) Client VM (build 1.5.0-beta2-b51, mixed mode, sharing)

*BUT*

This occurs for any JDK 1.4+

ADDITIONAL OS VERSION INFORMATION :
Windows XP
Windows (Any)

EXTRA RELEVANT SYSTEM CONFIGURATION :
My video setup is two NEC MultiSync LCD 1980SX monitors using
an NVIDIA Quadro NVS graphics card, though this problem would occur in any multi monitor environment.

A DESCRIPTION OF THE PROBLEM :
import java.awt.Frame;
import java.awt.Label;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.awt.Button;
import java.awt.BorderLayout;
import java.awt.Panel;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;

/**
 * Instructions:
 *
 * The following snippet demonstrates a severe performance regression in AWT
 * starting in 1.4 (merlin), and still present in the current version of the JDK
 * (tiger beta 2). In a multimonitor Windows XP environment set up as a single
 * display area (my video setup is two NEC MultiSync LCD 1980SX monitors using
 * an NVIDIA Quadro NVS graphics card), take the window and drag it rapidly
 * between the two monitors. In the AWT program, the event dispatch thread is
 * frozen while all of the surface datas are being recreated in the hierarchy
 * (in Win32SurfaceData.initOps). Note that the Swing program does not exhibit
 * the behavior because it does not have native peers.
 */
public class Test {

    private static final int NESTED_PANELS = 25;

    // This one is very slow!
    public static void testAWT() {
        Frame frame = new Frame("AWT Test");
        frame.addWindowListener(new WindowAdapter() {
            public void windowClosing(WindowEvent ev) {
                System.exit(0);
            }
        });
        frame.setLayout(new BorderLayout());
        Label label = new Label("Hello world");
        frame.add(label, BorderLayout.NORTH);
        Panel panel = new Panel(new BorderLayout());
        Panel currentPanel = panel;
        for (int i = 0; i < NESTED_PANELS; i++) {
            Panel newPanel = new Panel(new BorderLayout());
            currentPanel.add(newPanel, BorderLayout.CENTER);
            currentPanel = newPanel;
        }
        currentPanel.add(new Label("Test"));
        frame.add(panel, BorderLayout.CENTER);
        Button btn = new Button("OK");
        frame.add(btn, BorderLayout.SOUTH);
        frame.pack();
        frame.setVisible(true);
    }

    // This one works swell!
    public static void testSwing() {
        JFrame frame = new JFrame("Swing Test");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.getContentPane().setLayout(new BorderLayout());
        JLabel label = new JLabel("Hello world");
        frame.getContentPane().add(label, BorderLayout.NORTH);
        JPanel panel = new JPanel(new BorderLayout());
        JPanel currentPanel = panel;
        for (int i = 0; i < NESTED_PANELS; i++) {
            JPanel newPanel = new JPanel(new BorderLayout());
            currentPanel.add(newPanel, BorderLayout.CENTER);
            currentPanel = newPanel;
        }
        currentPanel.add(new Label("Test"));
        frame.getContentPane().add(panel, BorderLayout.CENTER);
        Button btn = new Button("OK");
        frame.getContentPane().add(btn, BorderLayout.SOUTH);
        frame.pack();
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        testAWT();
        // testSwing();
    }
}


STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
See the above code snippet documentation. Drag the window from one monitor to the other. Try to press the button.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
See the Swing version for bug-free behavior.
ACTUAL -
Exponential performance degredation depending on number of levels in the component hierarchy.

ERROR MESSAGES/STACK TRACES THAT OCCUR :
Stuck in Win32SurfaceData.initOps for all of the components while it exponentially goes through the hierarchy.

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
import java.awt.Frame;
import java.awt.Label;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.awt.Button;
import java.awt.BorderLayout;
import java.awt.Panel;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;

/**
 * Instructions:
 *
 * The following snippet demonstrates a severe performance regression in AWT
 * starting in 1.4 (merlin), and still present in the current version of the JDK
 * (tiger beta 2). In a multimonitor Windows XP environment set up as a single
 * display area (my video setup is two NEC MultiSync LCD 1980SX monitors using
 * an NVIDIA Quadro NVS graphics card), take the window and drag it rapidly
 * between the two monitors. In the AWT program, the event dispatch thread is
 * frozen while all of the surface datas are being recreated in the hierarchy
 * (in Win32SurfaceData.initOps). Note that the Swing program does not exhibit
 * the behavior because it does not have native peers.
 */
public class Test {

    private static final int NESTED_PANELS = 25;

    // This one is very slow!
    public static void testAWT() {
        Frame frame = new Frame("AWT Test");
        frame.addWindowListener(new WindowAdapter() {
            public void windowClosing(WindowEvent ev) {
                System.exit(0);
            }
        });
        frame.setLayout(new BorderLayout());
        Label label = new Label("Hello world");
        frame.add(label, BorderLayout.NORTH);
        Panel panel = new Panel(new BorderLayout());
        Panel currentPanel = panel;
        for (int i = 0; i < NESTED_PANELS; i++) {
            Panel newPanel = new Panel(new BorderLayout());
            currentPanel.add(newPanel, BorderLayout.CENTER);
            currentPanel = newPanel;
        }
        currentPanel.add(new Label("Test"));
        frame.add(panel, BorderLayout.CENTER);
        Button btn = new Button("OK");
        frame.add(btn, BorderLayout.SOUTH);
        frame.pack();
        frame.setVisible(true);
    }

    // This one works swell!
    public static void testSwing() {
        JFrame frame = new JFrame("Swing Test");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.getContentPane().setLayout(new BorderLayout());
        JLabel label = new JLabel("Hello world");
        frame.getContentPane().add(label, BorderLayout.NORTH);
        JPanel panel = new JPanel(new BorderLayout());
        JPanel currentPanel = panel;
        for (int i = 0; i < NESTED_PANELS; i++) {
            JPanel newPanel = new JPanel(new BorderLayout());
            currentPanel.add(newPanel, BorderLayout.CENTER);
            currentPanel = newPanel;
        }
        currentPanel.add(new Label("Test"));
        frame.getContentPane().add(panel, BorderLayout.CENTER);
        Button btn = new Button("OK");
        frame.getContentPane().add(btn, BorderLayout.SOUTH);
        frame.pack();
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        testAWT();
        // testSwing();
    }
}

---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
The fix (WPanelPeer.java) :

private void recursiveDisplayChanged(Component component)
    {
        if(component instanceof Container)
        {
            Component acomponent[] = ((Container)component).getComponents();
            for(int i = 0; i < acomponent.length; i++)
                recursiveDisplayChanged(acomponent[i]);
         }
         
        java.awt.peer.ComponentPeer componentpeer = component.getPeer();
        //sanjiv: added this if condition so that WPanelPeer displayChanged() is not called //which will again call this method
       System.out.println("Component : " + component.getName());
        if(componentpeer != null && (componentpeer instanceof WPanelPeer)){
         super.displayChanged();
        }
        else
        if(componentpeer != null && (componentpeer instanceof WComponentPeer))
        {
            WComponentPeer wcomponentpeer = (WComponentPeer)componentpeer;
            wcomponentpeer.displayChanged();
        }
    }
(Incident Review ID: 296521)
======================================================================