How do I convert time between timezone?

package org.kodejava.example.util;

import java.util.Calendar;
import java.util.GregorianCalendar;
import java.util.TimeZone;

public class TimeZoneExample {
    public static void main(String[] args) {
        // Create a calendar object and set it time based on the local
        // time zone
        Calendar localTime = Calendar.getInstance();
        localTime.set(Calendar.HOUR, 17);
        localTime.set(Calendar.MINUTE, 15);
        localTime.set(Calendar.SECOND, 20);

        int hour = localTime.get(Calendar.HOUR);
        int minute = localTime.get(Calendar.MINUTE);
        int second = localTime.get(Calendar.SECOND);

        // Print the local time
        System.out.printf("Local time  : %02d:%02d:%02dn", hour, minute, second);

        // Create a calendar object for representing a Germany time zone. Then we
        // wet the time of the calendar with the value of the local time
        Calendar germanyTime = new GregorianCalendar(TimeZone.getTimeZone("Germany"));
        hour = germanyTime.get(Calendar.HOUR);
        minute = germanyTime.get(Calendar.MINUTE);
        second = germanyTime.get(Calendar.SECOND);

        // Print the local time in Germany time zone
        System.out.printf("Germany time: %02d:%02d:%02dn", hour, minute, second);

How do I check if a year is a leap year?

The following example using the GregorianCalendar.isLeapYear() method to check if the specified year is a leap year.

package org.kodejava.example.util;

import java.util.GregorianCalendar;

public class LeapYearExample {
    public static void main(String[] args) {
        // Here we show how to know if a specified year is a leap year or 
        // not. The GregorianCalendar object provide a convenient method 
        // to do this. The method is GregorianCalendar.isLeapYear().

        // First, let's obtain an instance of GregorianCalendar.
        GregorianCalendar cal = new GregorianCalendar();

        // The isLeapYear(int year) method will return true for leap 
        // year and otherwise return false. In this example the message 
        // will be printed as 2016 is a leap year.
        if (cal.isLeapYear(2016)) {
            System.out.println("The year 2016 is a leap year!");

The result of our code is:

The year 2016 is a leap year!

Another code for checking leap year can be seen in the following example How do I know if a given year is a leap year?.