CheckoutPanelGUI

package edu.occ.or.cis2151;
import java.awt.BorderLayout;
import java.text.DecimalFormat;
import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;


public class CheckoutPanelGUI extends JFrame {

	private CustomerProfile profile;
	private OilChangePanel oil;
	private MaintenancePanel maintenance;
	private JPanel buttonPanel;
	private JButton calcButton;
	private JButton exitButton;
	private JButton estimateButton;
	private final double TAX_RATE = 0.06;


	public CheckoutPanelGUI() {

		// Title Display
		setTitle("Order Checkout");

		// How the programs closes on the exit button
		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);


		setLayout(new BorderLayout());

		//creating custom panels
		profile = new CustomerProfile();
		oil = new OilChangePanel();
		maintenance = new MaintenancePanel();

		//Creating components to the content of the window
		add(profile, BorderLayout.EAST);
		add(oil, BorderLayout.CENTER);
		add(maintenance, BorderLayout.WEST);
		add(buttonPanel, BorderLayout.SOUTH);

		pack();
		setVisible(true);
		}
		private void buildButtonPanel() {

		      // Create a panel for the buttons.
		      buttonPanel = new JPanel();

		      // Create the buttons.
		      calcButton = new JButton("Calculate");
		      estimateButton = new JButton("Estimate");
		      exitButton = new JButton("Exit");

		      // Register the action listeners.
		      calcButton.addActionListener(new CalcButtonListener());
		      exitButton.addActionListener(new ExitButtonListener());

		      // Add the buttons to the button panel.
		      buttonPanel.add(calcButton);
		      buttonPanel.add(exitButton);
		}


		private class CalcButtonListener implements ActionListener
		{
			public void actionPerformed(ActionEvent e)
			{
				double subtotal, tax, total;

				subtotal = oil.getOilCost() +
						   maintenance.getMaintenanceCost();

				tax = subtotal * TAX_RATE;

				total = subtotal + tax;

				DecimalFormat dollar = new DecimalFormat("0.00");

				JOptionPane.showMessageDialog(null,  "Subtotal: $" + dollar.format(subtotal) + "\n" + "Tax: $" + dollar.format(tax) + "\n" +
				"Total: $" + dollar.format(total));

			}
		}

	private class ExitButtonListener implements ActionListener
	{
		public void actionPerformed(ActionEvent e)
		{
			System.exit(0);
		}
	}

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