import java.awt.*;
import javax.swing.*;
public class GridLayoutManagerExample extends JFrame {

	public GridLayoutManagerExample (String title) {
		super(title);
		
		setLayout(new GridLayout(6,8,5,5));

		for (int row=1; row<=6; row++)
			for (int col=1; col<=8; col++) {
				JButton b = new JButton();
				if (Math.random() < 0.5)
					b.setBackground(Color.black);
				else
					b.setBackground(Color.white);
				add(b);
			}
				
		setDefaultCloseOperation(EXIT_ON_CLOSE);
		setSize(250, 200);
	}
	public static void main(String args[]) {
		GridLayoutManagerExample frame = new GridLayoutManagerExample("Grid Layout Example");
		frame.setVisible(true);
	}
}