Winston Tutorial 18 JCheckBox

package com.samkough.main;

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

@SuppressWarnings("serial")
public class Win extends JFrame implements ItemListener
{
	private static final int WIDTH = 500;
	private static final int HEIGHT = 300;

	JCheckBox jc1, jc2;
	JLabel l1, l2;

	public Win()
	{
		setLayout(new GridLayout(2,2));

		jc1 = new JCheckBox("Show first label");
		jc2 = new JCheckBox("Show second label");
		l1 = new JLabel("");
		l2 = new JLabel("");

		add(jc1);
		add(jc2);
		add(l1);
		add(l2);

		// we use itemListener because checkboxes can only use
		// itemListeners, not actionListeners
		jc1.addItemListener(this);
		jc2.addItemListener(this);
	}

	public void itemStateChanged(ItemEvent e)
	{
		// if the checkbox gets selected, then...
		if (jc1.isSelected())
		{
			l1.setText("You pushed the first checkbox.");
		}
		else
		{
			l1.setText("");
		}

		if (jc2.isSelected())
		{
			l2.setText("You pushed the second checkbox.");
		}
		else
		{
			l2.setText("");
		}
	}

	public static void main(String args[])
	{
		Win frame = new Win();

		frame.setVisible(true);
		frame.setSize(WIDTH, HEIGHT);
		// frame.pack();
		frame.setTitle("JCheckBox");
		frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		frame.setLocationRelativeTo(null);
	}
}