Java.util.TimeZone Class | Set 1

// Java program for Demonstration of
// getAvailableIDs() and
// getAvailableIDs(int rawOffset ) methods
import java.util.TimeZone;

public class TimeZoneDemo {

    public static void main(String[] args)
    {

        // get all the  timezones ids defined by TimeZone class
        String[] availableTimezones = TimeZone.getAvailableIDs();

        // Print Total no of TimeZones
        System.out.println("Total No of Time Zone Available");

        System.out.println(availableTimezones.length);

        // get all the  timezones  whose offset is
        // 7200000 milliseconds means 2 hour
        String[] timezones = TimeZone.getAvailableIDs(7200000);

        // Print Total no of TimeZones
        System.out.println("No of Time Zone having time offset 2 hour");

        System.out.println(timezones.length);

        // print all timezones names
        System.out.println("Timezone names having time offset 2 hour");

        for (int i = 0; i < timezones.length; i++)
            System.out.println(timezones[i]);
    }
}

// Java program for Demonstration of
// getDefault() and getDisplayName() methods
import java.util.TimeZone;

public class TimeZoneDemo {

    public static void main(String[] args)
    {

        // Get your Local Time Zone Where this Program is Running.
        TimeZone timezone = TimeZone.getDefault();

        // Get the Name of Time Zone
        String LocalTimeZoneDisplayName = timezone.getDisplayName();

        // Print the Name of Time Zone
        System.out.println(LocalTimeZoneDisplayName);
    }
}

// Java program for Demonstration of
// getTimeZone(String ID),
// getDSTSavings()  and getID() methods
import java.sql.Time;
import java.util.TimeZone;

public class TimeZoneDemo {

    public static void main(String[] args)
    {

        // creating Timezone object whose id is Europe/Berlin
        TimeZone timezone = TimeZone.getTimeZone("Europe/Berlin");

        // printing the Display Name of this timezone object
        System.out.println("Display Name");

        System.out.println(timezone.getDisplayName());

        // getting DST in milliseconds
        int timeInMilliseconds = timezone.getDSTSavings();

        System.out.println("\nDST of Europe/Berlin is");
        System.out.println(timezone.getDSTSavings());

        // get Id of your Default Time Zone
        TimeZone defaultTimezone = TimeZone.getDefault();

        System.out.println("\nThe id of default Time zone is");
        System.out.println(timezone.getID());
    }
}

// Java program for
// Demonstration of getOffset(long date),
// inDaylightTime(Date date)  and
// observesDaylightTime() methods
import java.sql.Time;
import java.util.*;

public class TimeZoneDemo {

    public static void main(String[] args)
    {

        // creating Timezone object whose id is Europe/Berlin
        TimeZone timezone = TimeZone.getTimeZone("Europe/Berlin");

        // printing offset value
        System.out.println("Offset value of Europe/Berlin:");

        System.out.println(timezone.getOffset(Calendar.ZONE_OFFSET));

        // create Date Object
        Date date = new Date(2017, 04, 16);

        // checking the date is in day light time of that Time Zone or not
        System.out.println("\nDate 16/04/2017 is in Day Light Time of");

        System.out.println("Timezone: timezone.getDisplayName()");
        System.out.println(timezone.inDaylightTime(date));

        // check this Time Zone observes Day Light Time or Not
        System.out.println("\nTimeZone name " + timezone.getDisplayName());

        System.out.println("Observes Day Light Time");
        System.out.println(timezone.observesDaylightTime());
    }
}

// Java program for Demonstration of
// setDefault(TimeZone zone),
// setID(String ID)  and clone() methods
import java.util.*;

public class TimeZoneDemo {

    public static void main(String[] args)
    {

        // My previous Default Time Zone is
        TimeZone DefaultTimeZone = TimeZone.getDefault();

        System.out.println("Current Default TimeZone:");
        System.out.println(DefaultTimeZone.getDisplayName());

        // Setting  Europe/Berlin as your Default Time Zone
        TimeZone timezone = TimeZone.getTimeZone("Europe/Berlin");

        timezone.setDefault(timezone);
        TimeZone NewDefaultTimeZone = TimeZone.getDefault();
        System.out.println("\nNew Default TimeZone:");
        System.out.println(NewDefaultTimeZone.getDisplayName());

        // change Id Europe/Berlin to Eur/Ber
        timezone.setID("Eur/Ber");

        System.out.println("\nNew Id of Europe/Berlin is");
        System.out.println(timezone.getID());

        // create copy of a time zone
        System.out.println("\nOriginal TimeZone ID:");

        System.out.println(timezone.getID());
        TimeZone clonedTimezone = (TimeZone)timezone.clone();
        System.out.println("Cloned TimeZone ID:");
        System.out.println(clonedTimezone.getID());
    }
}

// Java program to illustrate
// java.util.timezone class
import java.text.*;
import java.util.*;

public class TimeZoneDemo {

    public static void main(String[] args)
    {
        // Get your Local Time Zone Where this Program is Running.
        TimeZone timezone = TimeZone.getDefault();

        // Get the Name of Time Zone
        String LocalTimeZoneName = timezone.getDisplayName();

        // Initialize your Date Object and Date Format to represent your Date
        Date date = new Date();
        DateFormat dformat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");

        // set your local time Zone to your Date Format time Zone
        dformat.setTimeZone(timezone);

        // Print Date and Time for your Time Zone
        System.out.println("Date and time of your Local Time Zone:");
        System.out.println(LocalTimeZoneName + ", " + dformat.format(date));
    }
}