Help needed related java ! Thanx

Metric Class :

public class Metric

{

/**

The milesToKilometers method converts miles to kilometers.

@param m The distance in miles.

@return The distance in kilometers.

*/

public static double milesToKilometers(double m)

{

return m * 1.609;

}

/**

The kilometersToMiles method converts kilometers to miles.

@param k The distance in kilometers.

@return The distance in miles.

*/

public static double kilometersToMiles(double k)

{

return k / 1.609;

}

}

MetricDemo Class :

import javax.swing.JOptionPane;

import java.text.DecimalFormat;

/**

This program demonstrates the Metric class.

*/

public class MetricDemo

{

public static void main(String[] args)

{

String input; // To hold input

double miles; // A distance in miles

double kilos; // A distance in kilometers

// Create a DecimalFormat object.

DecimalFormat fmt = new DecimalFormat("0.00");

// Get a distance in miles.

input = JOptionPane.showInputDialog("Enter a distance in miles.");

miles = Double.parseDouble(input);

// Convert the distance to kilometers.

kilos = Metric.milesToKilometers(miles);

JOptionPane.showMessageDialog(null, fmt.format(miles) + " miles

equals " + fmt.format(kilos) + " kilometers.");

// Get a distance in kilometers.

input = JOptionPane.showInputDialog("Enter a distance in kilometers:

");

kilos = Double.parseDouble(input);

// Convert the distance to kilometers.

miles = Metric.kilometersToMiles(kilos);

JOptionPane.showMessageDialog(null, fmt.format(kilos) + " kilometers

equals " + fmt.format(miles) + " miles.");

System.exit(0);

}

}