A quick guide to get the current date time in milliseconds using Date, Calendar and java 8 api classes.
1. Overview
In this tutorial, We’ll learn how to get the time in milliseconds in java. Time in milliseconds is the right way and format in storing into the database for date time columns. Because this is stored as Number type and which reduces the space than DateTime type in SQL.
Let us come to our topic today is getting the time milliseconds can be retrieved from Date, Calendar and java 8 api classes such Instant, ZonedDateTime classes.
2. Using java.util.Date
First, we’ll try with the simple way to get the time in milliseconds format is from
Date class. Date class has a method
getTime() which returns the
milliseconds in long value for the given time or current time.
package com.javaprogramto.java8.dates.milliseconds;
import java.util.Date;
/**
* Example to get time in milli seconds in java using util Date api
*
* @author JavaProgramTo.com
*
*/
public class MilliSecondsFromDate {
public static void main(String[] args) {
// Getting the current date from Date class.
Date currentDate = new Date();
// Getting the time in milliseconds.
long milliSeconds = currentDate.getTime();
// printing the values
System.out.println("Current date : "+currentDate);
System.out.println("Current date time in milliseconds : "+milliSeconds);
// Creating the future date
Date futureDate = new Date(2025, 01, 01, 02, 30, 50);
// Getting the future date
milliSeconds = futureDate.getTime();
// printing the future date time values
System.out.println("Future date : "+futureDate);
System.out.println("Future date time in milliseconds : "+milliSeconds);
}
}Output:
Current date : Sat Dec 12 21:48:25 IST 2020 Current date time in milliseconds : 1607789905027 Future date : Sun Feb 01 02:30:50 IST 3925 Future date time in milliseconds : 61696501250000
3. Using java.util.Calendar
Next, use the
Calendar class to get the time in milli seconds. This class has a method
getTimeInMillis() which returns the milliseconds for the time.
package com.javaprogramto.java8.dates.milliseconds;
import java.util.Calendar;
import java.util.Locale;
/**
* Example to get time in milli seconds in java using Calendar api
*
* @author JavaProgramTo.com
*
*/
public class MilliSecondsFromCalendar {
public static void main(String[] args) {
// Getting the current date from Calendar class.
Calendar calendar = Calendar.getInstance();
// Getting the time in milliseconds.
long milliSeconds = calendar.getTimeInMillis();
// printing the values
System.out.println("Current calender time in milliseconds : "+milliSeconds);
// Creating another calendar object for Canada locale
Calendar canadaLocale = Calendar.getInstance(Locale.CANADA);
// Getting the future date
milliSeconds = canadaLocale.getTimeInMillis();
// printing the future date time values
System.out.println("Future date time in milliseconds : "+milliSeconds);
}
}Output:
Current calender time in milliseconds : 1607790439838 Future date time in milliseconds : 1607790439859
4. Using Java 8 API
There are multiple ways to get the date time in milliseconds in
java 8 date time api using Instant and ZonedDateTime classes.
Use
toEpochMilli() method to get the date time in milli seconds epoch format.
package com.javaprogramto.java8.dates.milliseconds;
import java.time.Instant;
import java.time.ZonedDateTime;
/**
* Example to get time in milli seconds in java 8 Using ZonedDateTime and Instant.
*
* @author JavaProgramTo.com
*
*/
public class MilliSecondsInJava8 {
public static void main(String[] args) {
// Getting milli seconds from ZonedDateTime class.
// Creating zoned date time
ZonedDateTime dateTime = ZonedDateTime.now();
// getting the instant from zoned date time
Instant instant = dateTime.toInstant();
// Converting Instant time to epoch format milli seconds
long timeInMilliSeconds = instant.toEpochMilli();
// print the output
System.out.println("Milli seconds from ZonedDateTime : "+timeInMilliSeconds);
// Getting the milli seconds from Instant class.
// Creating Instant object
Instant instantTime = Instant.now();
// Getting millis epoch value
timeInMilliSeconds = instantTime.toEpochMilli();
// printing
System.out.println("Milli seconds from Instant : "+timeInMilliSeconds);
}
}Output:
Milli seconds from ZonedDateTime : 1607790957290 Milli seconds from Instant : 1607790957291
5. Conclusion
In this article, we’ve seen
how to get the time in milli seconds in java 8 and older versions with examples.
Date class – use getTime() method
Calender class – use getTimeInMilli()
Java 8 api – use toEpochMilli()
Published on Java Code Geeks with permission by Venkatesh Nukala, partner at our JCG program. See the original article here: Java – Get Time In MilliSeconds Opinions expressed by Java Code Geeks contributors are their own. |
