java8 日期时间解析与转换

        Instant now = Instant.now();
        DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss").withZone(ZoneId.systemDefault());
        String formated = formatter.format(now);
        TemporalAccessor temporalAccessor = formatter.parse(formated);
        Instant instantNow = Instant.from(temporalAccessor);

        TemporalAccessor set = formatter.parse("2018-12-26 10:55:24");
        Instant instantSet = Instant.from(set);
        System.out.println(instantNow.isAfter(instantSet));