import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;


public class GridBagExample extends JPanel {
	private static final int WINDOW_WIDTH = 640;
	private static final int WINDOW_HEIGHT = 480;

	public static void main(final String[] args) {
		JFrame frame = new JFrame("Menu Example");
		GridBagExample panel = new GridBagExample();
		frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
		frame.setSize(WINDOW_WIDTH, WINDOW_HEIGHT);
		frame.setLocationRelativeTo(null);

		frame.setContentPane(panel);

		panel.initWidgets();

		frame.setVisible(true);
	}

	public void initWidgets() {
		setLayout(new GridBagLayout());
		
		GridBagConstraints c = new GridBagConstraints();
		
		JButton button1 = new JButton("First Button");
		c.gridx = 0;
		c.gridy = 0;
		//c.fill = GridBagConstraints.BOTH;
		//c.weightx = .5;
		add(button1, c);
		
		JButton button2 = new JButton("Second Button");
		c.gridx = 1;
		c.gridy = 0;
		//c.weightx = .9;
		//c.weighty = .5;
		c.insets = new Insets(20, 10, 30, 5);
		add(button2, c);
		
		JButton button3 = new JButton("This button takes two cells");
		c.gridx = 0;
		c.gridy = 1;
		c.gridwidth = 2;
		//c.weighty = .1;
		c.insets = new Insets(0, 0, 0, 0);
		c.ipady = 50;
		c.ipadx = 10;
		add(button3, c);
		
		JButton button4 = new JButton("Button on the side");
		c.gridx = 2;
		c.gridy = 0;
		c.gridheight = 2;
		c.anchor = GridBagConstraints.SOUTH;
		c.weightx = .5;
		add(button4, c);	
	}
}