import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class MainClass extends JPanel {
public MainClass() {
JButton btn1 = new JButton("Button1");
btn1.addActionListener(new ButtonListener());
add(btn1);
}
public static void main(String[] args) {
JFrame frame = new JFrame();
frame.getContentPane().add(new MainClass());
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(200, 200);
frame.setVisible(true);
}
}
class ButtonListener implements ActionListener {
ButtonListener() {
}
public void actionPerformed(ActionEvent e) {
if (e.getActionCommand().equals("Button1")) {
System.out.println("Button1 has been clicked");
}
}
}