import javax.swing.JPanel;import javax.swing.JFrame;import javax.swing.JRadioButton;import javax.swing.ButtonGroup;import java.awt.Dimension;import java.awt.Color;import java.awt.FlowLayout; public class JRadioButtonDemo{ public static void main(String[] args) {    JRadioButton red, white, cyan;  red = new JRadioButton ("red");  white = new JRadioButton ("white");  cyan = new JRadioButton ("cyan");   ButtonGroup group = new ButtonGroup ();  group.add (red);  group.add (white);  group.add (cyan);    JPanel panel = new JPanel (new FlowLayout (FlowLayout.CENTER, 1, 0));  panel.setBackground (Color.white);  panel.setPreferredSize (new Dimension (200,50));  panel.add (red);  panel.add (white);  panel.add (cyan);    JFrame frame = new JFrame("JRadioButtonDemo");  frame.setDefaultCloseOperation (JFrame.EXIT_ON_CLOSE);    frame.setContentPane(panel);  frame.pack();  frame.show(); }}

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