javaScript price calculator

sorry for the obvious dumb question but is the code below supposed to be saved as a htm file? how do i get the app to run properly.....?

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

/**
The OrderCalculatorGUI class creates the GUI for the application.
*/

public class OrderCalculatorGUI extends JFrame
{
private BagelPanel bagels; // Bagel panel
private ToppingPanel toppings; // Topping panel
private CoffeePanel coffee; // Coffee panel
private GreetingPanel banner; // To display a greeting
private JPanel buttonPanel; // To hold the buttons
private JButton calcButton; // To calculate the cost
private JButton exitButton; // To exit the application
private final double TAX_RATE = 0.06; // Sales tax rate


/**
Constructor
*/

public OrderCalculatorGUI()
{
// Display a title.
setTitle("Order Calculator");

// Specify an action for the close button.
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

// Create a BorderLayout manager.
setLayout(new BorderLayout());

// Create the custom panels.
banner = new GreetingPanel();
bagels = new BagelPanel();
toppings = new ToppingPanel();
coffee = new CoffeePanel();

// Create the button panel.
buildButtonPanel();

// Add the components to the content pane.
add(banner, BorderLayout.NORTH);
add(bagels, BorderLayout.WEST);
add(toppings, BorderLayout.CENTER);
add(coffee, BorderLayout.EAST);
add(buttonPanel, BorderLayout.SOUTH);

// Pack the contents of the window and display it.
pack();
setVisible(true);
}

/**
The buildButtonPanel method builds the button panel.
*/

private void buildButtonPanel()
{
// Create a panel for the buttons.
buttonPanel = new JPanel();

// Create the buttons.
calcButton = new JButton("Calculate");
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 inner class that handles the event when
the user clicks the Calculate button.
*/

private class CalcButtonListener implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
// Variables to hold the subtotal, tax, and total
double subtotal, tax, total;

// Calculate the subtotal.
subtotal = bagels.getBagelCost() +
toppings.getToppingCost() +
coffee.getCoffeeCost();

// Calculate the sales tax.
tax = subtotal * TAX_RATE;

// Calculate the total.
total = subtotal + tax;

// Create a DecimalFormat object to format output.
DecimalFormat dollar = new DecimalFormat("0.00");

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

/**
Private inner class that handles the event when
the user clicks the Exit button.
*/

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

 

That's not javascript, that is java. You are supposed to save it as .java and then compile it.