Changing Java Date one hour back

Question

I have a Java date object:

Date currentDate = new Date();

This will give the current date and time. Example:

Thu Jan 12 10:17:47 GMT 2012

Instead, I want to get the date, changing it to one hour back so it should give me:

Thu Jan 12 09:17:47 GMT 2012

What would be the best way to do it?

is there any `mktime` equivalent in java? subtract 60 minutes from it? — Shiplu Mokaddim, Jan 12 '12 at 10:21

Kimi · Accepted Answer · 2017-01-09T09:43:34.940

305

java.util.Calendar

Calendar cal = Calendar.getInstance();
// remove next line if you're always using the current time.
cal.setTime(currentDate);
cal.add(Calendar.HOUR, -1);
Date oneHourBack = cal.getTime();

java.util.Date

new Date(System.currentTimeMillis() - 3600 * 1000);

org.joda.time.LocalDateTime

new LocalDateTime().minusHours(1)

Java 8: java.time.LocalDateTime

LocalDateTime.now().minusHours(1)

Java 8 java.time.Instant

// always in UTC if not timezone set
Instant.now().minus(1, ChronoUnit.HOURS));
// with timezone, Europe/Berlin for example
Instant.now()
       .atZone(ZoneId.of("Europe/Berlin"))
       .minusHours(1));

edited Jan 09 '17 at 09:43

answered Jan 12 '12 at 10:20

Kimi

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Just be vary of the fact that there is Calendar.HOUR which works with 12 hour clock and Calendar.HOUR_OF_DAY for 24 hour clock: http://chintat.blogspot.ca/2006/05/calendarhour-vs-calendarhourofday.html – Wolf Apr 27 '15 at 17:24
Would the first solution with Calendar work if the time is midnight of one day and you want an hour early which is 11pm the previous day? – George Arokiam Sep 28 '18 at 14:51
1

@GeorgeArokiam yes it would – Kimi Oct 01 '18 at 14:00
Woow! This is a perfect short answer for most alternatives. – 4xMafole Sep 02 '21 at 21:35

Peter Lawrey · Answer 2 · 2016-01-19T13:52:19.177

75

Similar to @Sumit Jain's solution

Date currentDate = new Date(System.currentTimeMillis() - 3600 * 1000);

or

Date currentDate = new Date(System.currentTimeMillis() - TimeUnit.HOURS.toMillis(1));

edited Jan 19 '16 at 13:52

answered Jan 12 '12 at 10:59

Peter Lawrey

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Way better solution. Calendar instance creation looks like overkill in this particular application. – Leo Dec 26 '13 at 10:22
2

@cosmolev Calendar is overkill in most examples I find. – Peter Lawrey Dec 26 '13 at 10:39
2

@Stoan I have added a more readable example. You should note that Calendar is incredibly inefficient. – Peter Lawrey Jan 19 '16 at 13:53
@PeterLawrey `Date currentDate = new Date(System.currentTimeMillis() - TimeUnit.MINUTES.toMillis(10));` This should be 10 minutes behind? – Siya Sosibo Jan 19 '16 at 14:06

Basil Bourque · Answer 3 · 2019-01-25T00:10:02.463

tl;dr

In UTC:

Instant.now().minus( 1 , ChronoUnit.HOURS )

Or, zoned:

Instant.now()
       .atZone( ZoneId.of ( "America/Montreal" ) )
       .minusHours( 1 )

Using java.time

Java 8 and later has the new java.time framework built-in.

`Instant`

If you only care about UTC (GMT), then use the Instant class.

Instant instant = Instant.now ();
Instant instantHourEarlier = instant.minus ( 1 , ChronoUnit.HOURS );

Dump to console.

System.out.println ( "instant: " + instant + " | instantHourEarlier: " + instantHourEarlier );

instant: 2015-10-29T00:37:48.921Z | instantHourEarlier: 2015-10-28T23:37:48.921Z

Note how in this instant happened to skip back to yesterday’s date.

`ZonedDateTime`

If you care about a time zone, use the ZonedDateTime class. You can start with an Instant and the assign a time zone, a ZoneId object. This class handles the necessary adjustments for anomalies such as Daylight Saving Time (DST).

Instant instant = Instant.now ();
ZoneId zoneId = ZoneId.of ( "America/Montreal" );
ZonedDateTime zdt = ZonedDateTime.ofInstant ( instant , zoneId );
ZonedDateTime zdtHourEarlier = zdt.minus ( 1 , ChronoUnit.HOURS );

Dump to console.

System.out.println ( "instant: " + instant + "\nzdt: " + zdt + "\nzdtHourEarlier: " + zdtHourEarlier );

instant: 2015-10-29T00:50:30.778Z

zdt: 2015-10-28T20:50:30.778-04:00[America/Montreal]

zdtHourEarlier: 2015-10-28T19:50:30.778-04:00[America/Montreal]

Conversion

The old java.util.Date/.Calendar classes are now outmoded. Avoid them. They are notoriously troublesome and confusing.

When you must use the old classes for operating with old code not yet updated for the java.time types, call the conversion methods. Here is example code going from an Instant or a ZonedDateTime to a java.util.Date.

java.util.Date date = java.util.Date.from( instant );

…or…

java.util.Date date = java.util.Date.from( zdt.toInstant() );

About java.time

The java.time framework is built into Java 8 and later. These classes supplant the troublesome old legacy date-time classes such as java.util.Date, Calendar, & SimpleDateFormat.

The Joda-Time project, now in maintenance mode, advises migration to the java.time classes.

To learn more, see the Oracle Tutorial. And search Stack Overflow for many examples and explanations. Specification is JSR 310.

You may exchange java.time objects directly with your database. Use a JDBC driver compliant with JDBC 4.2 or later. No need for strings, no need for java.sql.* classes.

Where to obtain the java.time classes?

Java SE 8, Java SE 9, Java SE 10, Java SE 11, and later - Part of the standard Java API with a bundled implementation.
- Java 9 adds some minor features and fixes.
Java SE 6 and Java SE 7
- Most of the java.time functionality is back-ported to Java 6 & 7 in ThreeTen-Backport.
Android
- Later versions of Android bundle implementations of the java.time classes.
- For earlier Android (<26), the ThreeTenABP project adapts ThreeTen-Backport (mentioned above). See How to use ThreeTenABP….

The ThreeTen-Extra project extends java.time with additional classes. This project is a proving ground for possible future additions to java.time. You may find some useful classes here such as Interval, YearWeek, YearQuarter, and more.

Hello sir, I still cannot find the proper way to make "time ago" for the Instant. — Ticherhaz FreePalestine, Jun 02 '19 at 19:45

score 10 · Answer 4 · answered Jan 12 '12 at 10:20

10

Use Calendar.

Calendar cal = Calendar.getInstance();

cal.setTime(new Date());
cal.set(Calendar.HOUR, cal.get(Calendar.HOUR) - 1);

answered Jan 12 '12 at 10:20

adarshr

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Sumit Jain · Answer 5 · 2012-01-12T10:27:36.443

8

Just subtract the number of milliseconds in an hour from the date.

currentDate.setTime(currentDate.getTime() - 3600 * 1000));

edited Jan 12 '12 at 10:27

answered Jan 12 '12 at 10:21

Sumit Jain

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score 7 · Answer 6 · answered Jan 12 '12 at 10:24

7

Or using the famous Joda Time library:

DateTime dateTime = new DateTime();
dateTime = dateTime.minusHours(1);
Date modifiedDate = dateTime.toDate();

answered Jan 12 '12 at 10:24

Jean Logeart

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score 4 · Answer 7 · answered Aug 24 '16 at 05:24

You can use from bellow code for date and time :

DateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");
       //get current date time with Calendar()
       Calendar cal = Calendar.getInstance();
       System.out.println("Current Date Time : " + dateFormat.format(cal.getTime()));

       cal.add(Calendar.DATE, 1);
       System.out.println("Add one day to current date : " + dateFormat.format(cal.getTime()));

       cal = Calendar.getInstance();
       cal.add(Calendar.MONTH, 1);
       System.out.println("Add one month to current date : " + dateFormat.format(cal.getTime()));

       cal = Calendar.getInstance();
       cal.add(Calendar.YEAR, 1);
       System.out.println("Add one year to current date : " + dateFormat.format(cal.getTime()));

       cal = Calendar.getInstance();
       cal.add(Calendar.HOUR, 1);
       System.out.println("Add one hour to current date : " + dateFormat.format(cal.getTime()));

       cal = Calendar.getInstance();
       cal.add(Calendar.MINUTE, 1);
       System.out.println("Add one minute to current date : " + dateFormat.format(cal.getTime()));

       cal = Calendar.getInstance();
       cal.add(Calendar.SECOND, 1);
       System.out.println("Add one second to current date : " + dateFormat.format(cal.getTime()));

       cal = Calendar.getInstance();
       cal.add(Calendar.DATE, -1);
       System.out.println("Subtract one day from current date : " + dateFormat.format(cal.getTime()));

       cal = Calendar.getInstance();
       cal.add(Calendar.MONTH, -1);
       System.out.println("Subtract one month from current date : " + dateFormat.format(cal.getTime()));

       cal = Calendar.getInstance();
       cal.add(Calendar.YEAR, -1);
       System.out.println("Subtract one year from current date : " + dateFormat.format(cal.getTime()));

       cal = Calendar.getInstance();
       cal.add(Calendar.HOUR, -1);
       System.out.println("Subtract one hour from current date : " + dateFormat.format(cal.getTime()));

       cal = Calendar.getInstance();
       cal.add(Calendar.MINUTE, -1);
       System.out.println("Subtract one minute from current date : " + dateFormat.format(cal.getTime()));

       cal = Calendar.getInstance();
       cal.add(Calendar.SECOND, -1);
       System.out.println("Subtract one second from current date : " + dateFormat.format(cal.getTime()));

Output :

Current Date Time : 2008/12/28 10:24:53
Add one day to current date : 2008/12/29 10:24:53
Add one month to current date : 2009/01/28 10:24:53
Add one year to current date : 2009/12/28 10:24:53
Add one hour to current date : 2008/12/28 11:24:53
Add one minute to current date : 2008/12/28 10:25:53
Add one second to current date : 2008/12/28 10:24:54
Subtract one day from current date : 2008/12/27 10:24:53
Subtract one month from current date : 2008/11/28 10:24:53
Subtract one year from current date : 2007/12/28 10:24:53
Subtract one hour from current date : 2008/12/28 09:24:53
Subtract one minute from current date : 2008/12/28 10:23:53
Subtract one second from current date : 2008/12/28 10:24:52

This link is good : See here

And see : See too

And : Here

If you need just time :

DateFormat dateFormat = new SimpleDateFormat("HH:mm:ss");

FYI: This Answer uses troublesome old Date-time classes that are now legacy, supplanted by the modern java.time classes. — Basil Bourque, Oct 25 '17 at 15:36

score 3 · Answer 8 · edited Nov 07 '17 at 05:12

3

This can be achieved using java.util.Date. The following code will subtract 1 hour from your date.

Date date = new Date(yourdate in date format);
Date newDate = DateUtils.addHours(date, -1)

Similarly for subtracting 20 seconds from your date

newDate = DateUtils.addSeconds(date, -20)

edited Nov 07 '17 at 05:12

Sudheesh Singanamalla

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answered Nov 07 '17 at 05:00

Dhananjay

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score 0 · Answer 9 · answered Oct 17 '20 at 15:02

To subtract hours, you need to use the HOUR_OF_DAY constant. Within that, include the number with the negative sign. This would be the hours you want to reduce. All this is done under the Calendar add() method.

The following is an example:

import java.util.Calendar;
public class Example {
  public static void main(String[] args) {
   Calendar c = Calendar.getInstance();
     System.out.println("Date : " + c.getTime());
       // 2 hours subtracted
   c.add(Calendar.HOUR_OF_DAY, -2);
   System.out.println("After subtracting 2 hrs : " + c.getTime());
 }
}

Here is the output:

Date : Sun Dec 16 16:28:53 UTC 2018
After subtracting 2 hrs : Sun Dec 16 14:28:53 UTC 2018

I recommend you don’t use `Calendar`. That class is poorly designed and long outdated. Instead use for example `ZonedDateTime` from [java.time, the modern Java date and time API](https://docs.oracle.com/javase/tutorial/datetime/). Your answer would have been a good one in 2012 when the question was asked, but frankly it’s a poor one for 2020. Also are you contributing anything that isn’t already in more than one other answer? — Ole V.V., Oct 18 '20 at 13:00

score -1 · Answer 10 · answered Oct 25 '17 at 08:22

-1

Get the time in milliseconds, minus your minutes in milliseconds and convert it to Date. Here you need to objectify one!!!

    int minutes = 60;
    long currentDateTime = System.currentTimeMillis();
    Date currentDate = new Date(currentDateTime - minutes*60*1000);
    System.out.println(currentDate);

answered Oct 25 '17 at 08:22

Zenith

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@Makky: I know things have changed. But its not a wrong answer!!! Why do you tell this a wrong answer? Did you see the accepted answer fully? – Zenith Oct 25 '17 at 09:07
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Why would you even answer to a question which is 5 years old and has accepted answer. – Makky Oct 25 '17 at 12:07
This Answer provides no value beyond the existing years-old Answers. And this Answer unwisely uses terrible old date-time classes that have been supplanted for years by the java.time classes. Another problem: this Answer ignores the issue of time zone, and shows code that will use the JVM’s current default time zone while the Question asked for GMT/UTC. See the later parts of the [correct Answer by Kimi](https://stackoverflow.com/a/8833424/642706) or see [my Answer](https://stackoverflow.com/a/33404165/642706) for more discussion. – Basil Bourque Oct 25 '17 at 15:30

score -1 · Answer 11 · answered Jan 24 '19 at 11:41

-1

It worked for me instead using format .To work with time just use parse and toString() methods

String localTime="6:11"; LocalTime localTime = LocalTime.parse(localtime)

LocalTime lt = 6:11; localTime = lt.toString()

answered Jan 24 '19 at 11:41

Shahid Hussain Abbasi

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This Answer does not address the Question. The Question is about more than a time-of-day alone. – Basil Bourque Jan 25 '19 at 00:09