如何将秒从日期时间转换为时间戳？

Question

Good day. Such a question - there is a method in python that gets datetime and converts it into a timestamp:

source = 'Friday 9:14 PM March 9 2018'
central_tz = pytz.timezone('Canada/Eastern')
utc_tz = pytz.timezone('UTC')

naive_dt = datetime.datetime.strptime(source, "%A %I:%M %p %B %d %Y")
utc_ts = time.mktime(utc_dt.timetuple())
print(central_tz.localize(native_dt, is_dst=None))
print("naite_dt")
print(naive_dt)
central_dt = central_tz.localize(naive_dt, is_dst=None)
print("central_dt")
print(central_dt)
utc_dt = central_dt.astimezone(pytz.utc)
print("utc_dt")
print(utc_dt)
utc_ts = time.mktime(utc_dt.timetuple())
print("utc_ts")
print(utc_ts)

On output:

naite_dt
2018-03-09 21:14:00
central_dt
2018-03-09 21:14:00-05:00
utc_dt
2018-03-10 02:14:00+00:00
utc_ts
1520640840.0

And I have implementation of the same method in java:

public static void scraper() throws ParseException {
        String source = "2018 марта 9, 09:14 PM";
        String pattern = "yyyy MMMM dd, KK:mm a";
        String central_tz = "Canada/Eastern";
        String utc_tz = "UTC";

        DateFormat dt = new SimpleDateFormat(pattern);
        dt.setTimeZone(TimeZone.getTimeZone(central_tz));

        Date date = dt.parse(source);
        String formatted = dt.format(date);
        System.out.println("Время по Канаде: " + formatted);

        dt.setTimeZone(TimeZone.getTimeZone(utc_tz));
        formatted = dt.format(date);
        System.out.println("Время по UTC: " + formatted);

        Timestamp timestmp = Timestamp.from(date.toInstant());
        System.out.println("Время Timestamp: " + timestmp.toString());
        System.out.println("Время в секундах Timestamp: " + timestmp.getTime() / 1000);
    }

But it's output and it's true output:

Время по Канаде: 2018 марта 09, 09:14 PM
Время по UTC: 2018 марта 10, 02:14 AM
Время Timestamp: 2018-03-10 04:14:00.0
Время в секундах Timestamp: 1520648040

On final we have output timestamp in Python 1520640840 and output timestamp in Java 1520648040 - it's different!!! Why? And woh I can fixed it in Python? Thank's

Answer 1

If you notice the time shown in python is which you are using to convert into timestamp and in Java when you are using the date variable which has the time

There's a 2 hour difference between both. Try to find why that happened. What I think is you are in timezon UTC +2 therefore the date variable stored the time as 4:14 am for which you did not set a time zone and in python your date variable " utc_dt " used for converting in timestamp has the timezone UTC hence its time is 2:14 am.

You can verify this by calculating the difference between both timestamps which is 7200 which means 2 hours. So in fact your Java time stamp is set according to your local time zone and python timestamp is set according to the UTC time zone.