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import javax.swing.JFrame;
import java.awt.Toolkit;
import java.awt.Dimension;

public class Window {
	
	public static void main(String args[]) {
		int width = 400;
		int height = 300;
		JFrame frame = new JFrame();
		frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		frame.setSize(width, height);
		Toolkit toolkit = Toolkit.getDefaultToolkit();
		Dimension d = toolkit.getScreenSize();
		frame.setLocation(((int)d.getWidth() - width) / 2, ((int)d.getHeight() - height) / 2);
		frame.setVisible(true);
	}
	
}