import java.awt.Graphics;
import javax.swing.JPanel;
public class DrawPanel extends JPanel
{

public void paintComponent(Graphics g)
 {
 super.paintComponent(g);
 int width = getWidth();
 int height = getHeight();

 g.drawLine(0,0, width, height);
 g.drawLine(0,height, width,0);
 }
}
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my second code is this...

import javax.swing.JFrame;

public class DrawPanelTest
{


public static void main(String args[])
 {
 DrawPanel panel = new DrawPanel();
 JFrame application = new JFrame();
 application.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
 application.add(panel);
 application.setSize(250,250);
 application.setVisible(true);
}
}
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i hope that you can help me whith my problem....