Calculate a user's BMI when prompted for their weight and height.

BMI.java

    import java.util.InputMismatchException;
    import java.util.Scanner;

    public class BMI {

        static double userWeight;  // Given to the nearest kilogram
        static double userHeight; // Given in meters
        static float userBMI; //

        /**
         * Calculate the user's BMI via
         * @param args Unused for the purposes of this program.
         * */
         
        public static void main(String[] args) {

            Scanner scanner = new Scanner(System.in);

            System.out.print("What is your weight in kg? ");

            try {
                userWeight = scanner.nextDouble();
            } catch (InputMismatchException exception) {
                System.out.print("The weight retrieved does not match the pattern for the primitive int.");
                return;
            }

            System.out.print("What is your height in metres?");

            try {
                userHeight = scanner.nextDouble();
            } catch (InputMismatchException exception) {
                System.out.print("The height retrieved does not match the pattern for double.");
                return;
            }

            scanner.close();

            try {
                // The Definition of the BMI, or Body-Mass Index is defined as the user's weight, divided by the square of their height.
                userBMI = (float) (userWeight / Math.pow(userHeight, 2));
            } catch(ClassCastException exception) {
                System.out.print("An unknown error occurred, please see the stack trace below.");
                exception.printStackTrace();
                return;
            }

            System.out.print("Your BMI is " + userBMI);
        }
    }