TrafficLight1.java

import java.awt.*;
//import java.awt.event.*;

import javax.swing.*;

class App  implements ActionListener{
	JFrame jfrm;
		JLabel message;
	ButtonGroup btngroup;
	JRadioButton rbred, rbyellow, rbgreen;
	
	App() {
		
		jfrm = new JFrame("Traffic Lights");
		message = new JLabel("Select Light");
		btngroup = new ButtonGroup();
		rbred = new JRadioButton("Red");
		rbyellow = new JRadioButton("Yellow");
		rbgreen = new JRadioButton("Green");
		
		jfrm.setLayout(new FlowLayout());
		
		rbred.setForeground(Color.RED);
		rbyellow.setForeground(Color.YELLOW);
		rbgreen.setForeground(Color.GREEN);
		
		btngroup.add(rbred);
		btngroup.add(rbyellow);
		btngroup.add(rbgreen);
		
		rbred.addActionListener(this);
		rbyellow.addActionListener(this);
		rbgreen.addActionListener(this);
		
		jfrm.add(message);
		jfrm.add(rbred);
		jfrm.add(rbyellow);
		jfrm.add(rbgreen);
		
				
		jfrm.setSize(300, 200);
		jfrm.setVisible(true);
	}


	public void actionPerformed(ActionEvent ie) {
				String txt = ie.getActionCommand();
		if(txt.equals("Red")) {
			message.setForeground(Color.RED);
			message.setText("STOP");
		} else if(txt.equals("Yellow")) {
			message.setForeground(Color.YELLOW);
			message.setText("READY");
		} else {
			message.setForeground(Color.GREEN);
			message.setText("GO");
		}
	}
}
public class TrafficLight1 {

	public static void main(String[] args) {
		new App();
	}

}