public class Test { public static void main(String[] args) throws UnsupportedEncodingException { DateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"); Date date = null; Date date1 = null; date = new Date(System.currentTimeMillis() + (365 * 24 * 60 * 60 * 1000L)); date1 = new Date(1621329814000L); System.out.println(dateFormat.format(date)); System.out.println(dateFormat.format(date1)); System.out.println(new String(Base64.getDecoder().decode("eyJ0eXAiOiJKV1QiLCJhbGciOiJSUzI1NiJ9".getBytes("utf-8")))); } }