FULL PRODUCT VERSION :
java version " 1.6.0.30 "
Java<TM> SE Runtime Environment (build 1.6.0_30-b12)
Java HotSpot(TM) Client VM (build 20.5-b03, mixed mode, sharing)

ADDITIONAL OS VERSION INFORMATION :
Microsoft Windows [Version 6.1.7601]

A DESCRIPTION OF THE PROBLEM :
On JPanel, clipping doesn't work after when I call setXORMode method like below code.

    g2.setXORMode(Color.white);

After this I drew rectangle but it wasn't clipped as i did.

I think JPanel can't handle these kind of thing. it's ok. when i using awt .



REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
import java.awt.*;
import java.awt.event.*;
import java.awt.geom.Area;
import java.awt.geom.RoundRectangle2D;

import javax.swing.*;
import javax.swing.event.*;

///////////////////////////////////////////////////// DemoDrawing2
public class DemoDrawing2 extends JFrame {

    //===================================================== fields
    private DrawingArea left = new DrawingArea();
    

    //================================================ Constructor
    public DemoDrawing2() {
        left.setBackground(Color.white);
        
        JButton changeColorBtn = new JButton( " Randomize Colors " );
        changeColorBtn.addActionListener(new ActionListener() {
                public void actionPerformed(ActionEvent e) {
                    left.setMyColor(randomColor());
                }
            });

        //... Add components to layout
        JPanel content = new JPanel();
        content.setLayout(new BorderLayout(5, 5));
        content.add(changeColorBtn, BorderLayout.NORTH);
        content.add(left, BorderLayout.CENTER);
        
        //... Set window characteristics
        setContentPane(content);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setTitle( " Demo Drawing " );
        setLocationRelativeTo(null); // Center window.
        pack();
    }


    //=================================================== randomColor
    private static Color randomColor() {
        return new Color((int) (Math.random() * 256), // Red
                         (int) (Math.random() * 256), // Green
                         (int) (Math.random() * 256)); // Blue
    }


    //========================================================== main
    public static void main(String[] args) {
        JFrame window = new DemoDrawing2();
        window.setVisible(true);
    }
}

///////////////////////////////////////////////////////// DrawingArea
class DrawingArea extends JPanel {

//======================================================== fields
private Color _ovalColor; // Color of oval.

//=================================================== constructor
public DrawingArea() {
_ovalColor = Color.GREEN; // Initial color.
setPreferredSize(new Dimension(100,100));
}

//================================================ paintComponent
@Override public void paintComponent(Graphics g) {
super.paintComponent(g); // Ask parent to paint background.

Graphics2D g2 = (Graphics2D)g;
g2.setColor(_ovalColor);
int w = getWidth(); // Size might have changed if
int h = getHeight(); // user resized window.
Area areaRoundRect = new Area(new RoundRectangle2D.Double(0, 0, w, h, 70.0f, 70.0f));
g2.clip(areaRoundRect);
g2.setXORMode(Color.white);
g2.fillRect(0, 0, w, h);
}

//==================================================== setMyColor
public void setMyColor(Color col) {
_ovalColor = col; // Remember color.
repaint(); // Color changed, must repaint
}
}

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