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javalong-integercountdown

Christmas Countdown Off

I am trying to make a Christmas countdown in java however I cannot seem to figure out why the hours are off. This is outputting about 12 hours off from the actual time.

Here is my code:

long now = System.currentTimeMillis();
long christmas = 1387929600000L;
long untilChristmas = christmas - now;

DateFormat df = new SimpleDateFormat("dd-kk-mm-ss");
Date date = new Date(untilChristmas);

System.out.println(df.format(date));
Solution

  • You shouldn't hardcode the date, you should use a Calendar to calculate it:

        long now = System.currentTimeMillis();
    Calendar christmas = Calendar.getInstance();
    christmas.set(Calendar.MONTH, Calendar.DECEMBER);
    christmas.set(Calendar.DAY_OF_MONTH, 25);
    long untilChristmas = christmas.getTimeInMillis() - now;

    DateFormat df = new SimpleDateFormat("dd-kk-mm-ss");
    Date date = new Date(untilChristmas);

    System.out.println(df.format(date));