import javax.swing.*;
import java.awt.*;
 
public class FrameUpdateTest
{
    private final JFrame mainWindow = new JFrame();
 
    private void launch()
    {
        mainWindow.getContentPane().setBackground(Color.WHITE);
        mainWindow.setSize(1000, 800);
        mainWindow.setLocationRelativeTo(null);
        mainWindow.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        mainWindow.setVisible(true);
    }
 
    public static void main(String[] args)
    {
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
               new FrameUpdateTest().launch();
            }
        });
    }
}