code: @SuppressWarnings("resource")
  	public static void main(String[] args) {
  		try {
  			System.out.println("Select (k=generate key; c=crypt; d=decrypt):");
  			System.out.println();
  			Scanner scan = new Scanner(System.in, "UTF-8");
  			if (!scan.hasNextLine()) {
  				return;
  			}
  			switch (scan.nextLine()) {
  			case "k":
  				MessageCryptoUtil.generateKey();
  				break;
  			case "c":
  				System.out.print("Input data: ");
  				final String data = scan.nextLine();
  				System.out.println(MessageCryptoUtil.crypt(data));
  				break;
  			case "d":
  				System.out.print("Input data: ");
  				final String ddata = scan.nextLine();
  				System.out.println(MessageCryptoUtil.decrypt(ddata));
  				break;
  			default:
  				break;
  			}
  		} catch (final Exception e) {
  			e.printStackTrace();
  		}
  	}
docs: start this to generate an AES key or (de/en)crypt data
  
  @param args the CLI arguments