Java如何获取ISO 8601时间

        DateFormat df = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'");
        df.setTimeZone(TimeZone.getTimeZone("UTC"));
        String timestamp = df.format(new Date());
        System.out.println("timestamp = " + timestamp);//timestamp = 2019-06-14T02:05:14.302Z