TripleDES Encryption Hardner and Softner

gistfile1.txt

public String harden(String unencryptedString) throws NoSuchAlgorithmException, UnsupportedEncodingException, NoSuchPaddingException, InvalidKeyException, IllegalBlockSizeException, BadPaddingException {
        MessageDigest md = MessageDigest.getInstance("md5");
        byte[] digestOfPassword = md.digest(key.getBytes("utf-8"));
        byte[] keyBytes = Arrays.copyOf(digestOfPassword, 24);

        for (int j = 0, k = 16; j < 8;) {
            keyBytes[k++] = keyBytes[j++];
        }

        SecretKey secretKey = new SecretKeySpec(keyBytes, "DESede");
        Cipher cipher = Cipher.getInstance("DESede/ECB/PKCS5Padding");
        cipher.init(Cipher.ENCRYPT_MODE, secretKey);

        byte[] plainTextBytes = unencryptedString.getBytes("utf-8");
        byte[] buf = cipher.doFinal(plainTextBytes);
        byte[] base64Bytes = Base64.encodeBase64(buf);
        String base64EncryptedString = new String(base64Bytes);

        return base64EncryptedString;
    }
    
    public String soften(String encryptedString) throws UnsupportedEncodingException, NoSuchAlgorithmException, NoSuchPaddingException, InvalidKeyException, IllegalBlockSizeException, BadPaddingException {
        if(encryptedString == null)
        {
            return "";
        }
        byte[] message = Base64.decodeBase64(encryptedString.getBytes("utf-8"));

        MessageDigest md = MessageDigest.getInstance("MD5");
        byte[] digestOfPassword = md.digest(key.getBytes("utf-8"));
        byte[] keyBytes = Arrays.copyOf(digestOfPassword, 24);
        
        for (int j = 0, k = 16; j < 8;) {
            keyBytes[k++] = keyBytes[j++];
        }
        
        SecretKey secretKey = new SecretKeySpec(keyBytes, "DESede");

        Cipher decipher = Cipher.getInstance("DESede/ECB/PKCS5Padding");
        decipher.init(Cipher.DECRYPT_MODE, secretKey);

        byte[] plainText = decipher.doFinal(message);

        return new String(plainText, "UTF-8");

    }