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androidjava-calendar

How to set Calendar according to Timezone

I want to make a Calendar according to Timezone. I tried to resolve the issue by surfing different queries but i can't. Now it pick mobile default time. If anyone have idea please help me. Timezone should be UK time.

I tried:

{
    Calendar c1;
    c1 = Calendar.getInstance(TimeZone.getTimeZone("UTC"), Locale.UK);
    int hour = c1.get(Calendar.HOUR);
    int minutes = c1.get(Calendar.MINUTE);
    int seconds = c1.get(Calendar.SECOND);
    int day = c1.get(Calendar.DAY_OF_MONTH);
    int month = c1.get(Calendar.MONTH);
    int year = c1.get(Calendar.YEAR);
}

But it also returns System date.

Solution

  • java.time

        ZonedDateTime nowInUk = ZonedDateTime.now(ZoneId.of("Europe/London"));
    int hour = nowInUk.getHour();
    int minutes = nowInUk.getMinute();
    int seconds = nowInUk.getSecond();
    int day = nowInUk.getDayOfMonth();
    Month month = nowInUk.getMonth();
    int year = nowInUk.getYear();

    System.out.println("hour = " + hour + ", minutes = " + minutes + ", seconds = " + seconds 
            + ", day = " + day + ", month = " + month + ", year = " + year);

    When I ran this snippet just now, it printed:

    hour = 3, minutes = 41, seconds = 15, day = 5, month = OCTOBER, year = 2018

    ZonedDateTime largely replaces the outdated Calendar class.

    What went wrong in your code?

    Time zone ID for UK time is Europe/London. In your code you used UTC, which is something else and wll give you a different result, at least sometimes. UK time coincides with UTC some of the year in some years, but not at this time of year this year. So you got a time that was one hour earlier than UK time.

    Also c1.get(Calendar.HOUR) gives you the hour within AM or PM from 1 through 12, which I don’t think was what you intended.

    Question: Can I use java.time on Android?

    Yes, java.time works nicely on Android devices. It just requires at least Java 6.

    • In Java 8 and later and on new Android devices (from API level 26, I’m told) the new API comes built-in.
    • In Java 6 and 7 get the ThreeTen Backport, the backport of the new classes (ThreeTen for JSR 310, where the modern API was first described).
    • On (older) Android, use the Android edition of ThreeTen Backport. It’s called ThreeTenABP. Make sure you import the date and time classes from package org.threeten.bp and subpackages.

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