import javax.swing.*;
import java.awt.event.*;
public class Helloworld 
{
	public static void main(String[] args) 
	{
		JFrame f = new JFrame("Hello world");
		JPanel panel = new JPanel();
		JButton button = new JButton("Press me!");
		button.addActionListener(new ActionListener()
		{
			public void actionPerformed(ActionEvent event)
			{
				System.out.println("You pressed me!");
			}
		});
		panel.add(button);
		f.add(panel);
		f.pack();
		f.setVisible(true);
	}
}