Sample Program to Show how to calculate Hash value using MD5 and SHA1 in Java

Main.java

package com.causecode.sample;

import javax.xml.bind.annotation.adapters.HexBinaryAdapter;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Scanner;

/**
 * Demo Program to show how to calculate the hash code for the given input
 */
public class Main {

    /**
     * Enum representing Algorithms
     */
    private enum Algorithm {
        MD5,
        SHA1
    }

    /**
     * Main Entry Point for Java JVM
     * @param args
     * @throws NoSuchAlgorithmException
     */
    public static void main(String[] args) throws NoSuchAlgorithmException {
        Scanner scanner = new Scanner(System.in);
        printToConsole("Enter the input to calculate the hash ? ");
        String input = scanner.nextLine();

        printToConsole("----------------------");
        printToConsole("Chose Algorithm..");
        printToConsole("1) MD5");
        printToConsole("2) SHA1");
        int choice = scanner.nextInt();
        scanner.close();

        String hash;
        if (choice == 1) {
            hash = calculateHash(input, Algorithm.MD5);
        } else {
            hash = calculateHash(input, Algorithm.SHA1);
        }

        printToConsole("----------------------");
        printToConsole(String.format("Calculated Hash for Given Input is:- \" %s \"", convertHashToHexString(hash)));

    }

    /**
     * Convert Given Hash to Hex Representation
     * @param hash
     * @return String
     */
    private static String convertHashToHexString(String hash) {
        return new HexBinaryAdapter().marshal(hash.getBytes());
    }


    /**
     * Calculates the hash for the given input using supplied Algorithm
     * @param message
     * @param algorithm
     * @return
     * @throws NoSuchAlgorithmException
     */
    static String calculateHash(String message, Algorithm algorithm) throws NoSuchAlgorithmException {
        return String.valueOf(MessageDigest.getInstance(algorithm.toString()).digest(message.getBytes()));
    }

    /**
     * Utility Method to print line to the console
     * @param message
     */
    static void printToConsole(String message) {
        System.out.println(message);
    }
}