How To Add Days To Current Date In Java 8? Increment/Decrement Date Examples

1. Overview

In this quick tutorial, you'll learn how to increment the days to the current date and time in java.

This is quite regularly used in the software developer life.

Let us look into the examples using java.util.calendar api and new java 8 Date Time api.

This is also similar to the how to add minutes to the current date in java 8?

2. Example to add days to current time with Calendar.add() method

Java Calendar api has a special add() method that increment the given number for given unit.

Look at the below example that adds the 2 years 2 months 2 days to the current date.

Read the comments in the program for better understanding.

package com.javaprogramto.java8.dates;

import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;

public class AddDaysExample {
	public static void main(String[] args) {
		// creating date in java
		Date date = new Date();
		
		// printing the date in the readable format.
		SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");
		String dateStr = dateFormat.format(date);
		System.out.println("Current date : "+dateStr);
		
		//creating calender instance 
		Calendar calendar = Calendar.getInstance();
		calendar.setTime(date);
		
		// adding 2 years, months and date
		calendar.add(Calendar.YEAR, 2);
		calendar.add(Calendar.MONTH, 2);
		calendar.add(Calendar.DATE, 2);
		
		// getting the new date from calendar
		Date addedDate = calendar.getTime();
		
		// printing the new date
		String newDateinStr = dateFormat.format(addedDate);
		System.out.println("New date after adding 2 years : "+newDateinStr);
		
	}
}

Output:

Current date : 2020-11-16
New date after adding 2 years : 2023-01-18

3. Example to add days to current time with new Java 8 Date API

New java 8 api has come up with the new methods such as plus and minus date operations.

All LocalDateTime methods can be used as chained methods but need to store the result into localdatetime variable.

3.1 plusYears() + plusMonths() + plusDays() Example

Next, let us increment the current date by 2 years, 2 months, 2 days, 2 hours, 2 minutes, 2 seconds.

plus methods are declared as read friendly such plusYears(), plusMonths(), plusDays() and easy to remember.

plusYears() - to add years

plusMonths() - to add months

plusDays()  - to add days

plusHours() - to add hours

plusMinutes() - to add minutes

plusSeconds() - to add seconds

package com.javaprogramto.java8.dates;

import java.text.SimpleDateFormat;
import java.time.LocalDateTime;
import java.time.ZoneId;
import java.time.format.DateTimeFormatter;
import java.util.Date;

public class Java8AddDaysExample {
	public static void main(String[] args) {
		// date formats
		String format = "yyyy-MM-dd hh:mm:ss";
		SimpleDateFormat dateFormat = new SimpleDateFormat(format);

		// Date format in java 8
		DateTimeFormatter dateFormat8 = DateTimeFormatter.ofPattern(format);

		// creating date in java
		Date date = new Date();

		// printing the date in the readable format.
		String dateStr = dateFormat.format(date);
		System.out.println("Current date : " + dateStr);

		// converting date to LocalDateTime
		LocalDateTime localDateTime = date.toInstant().atZone(ZoneId.systemDefault()).toLocalDateTime();
		System.out.println("localDateTime : " + dateFormat8.format(localDateTime));

		localDateTime = localDateTime.plusYears(2);
		localDateTime = localDateTime.plusMonths(2);
		localDateTime = localDateTime.plusDays(2);

		localDateTime = localDateTime.plusHours(2).plusMinutes(2).plusSeconds(2);

		// converting LocalDateTime to Date
		Date currentDatePlus = Date.from(localDateTime.atZone(ZoneId.systemDefault()).toInstant());

		// printing the new date
		String newDateinStr = dateFormat.format(currentDatePlus);
		System.out.println("New date after adding 2 years : " + newDateinStr);

	}
}

Output:

Current date : 2020-11-16 03:00:43
localDateTime : 2020-11-16 03:00:43
New date after adding 2 years : 2023-01-18 05:02:45

3.2 minusYears() + minusMonths() + minusDays() Example

Next, let us decrement the current date by 2 years, 2 months, 2 days, 2 hours, 2 minutes, 2 seconds.

minusYears() - to decrement or minus years

minusMonths() - to decrement or minus months

minusDays()  - to decrement or minus days

minusHours() - to decrement or minus hours

minusMinutes() - to decrement or minus minutes

minusSeconds() - to decrement or minus seconds

package com.javaprogramto.java8.dates;

import java.text.SimpleDateFormat;
import java.time.LocalDateTime;
import java.time.ZoneId;
import java.time.format.DateTimeFormatter;
import java.util.Date;

/**
 * To remove the date from current date time.
 * 
 * @author javaprogramto.com
 *
 */
public class Java8MinusDaysExample {
	public static void main(String[] args) {
		// date formats
		String format = "yyyy-MM-dd hh:mm:ss";
		SimpleDateFormat dateFormat = new SimpleDateFormat(format);

		// Date format in java 8
		DateTimeFormatter dateFormat8 = DateTimeFormatter.ofPattern(format);

		// creating date in java
		Date date = new Date();

		// printing the date in the readable format.
		String dateStr = dateFormat.format(date);
		System.out.println("Current date : " + dateStr);

		// converting date to LocalDateTime
		LocalDateTime localDateTime = date.toInstant().atZone(ZoneId.systemDefault()).toLocalDateTime();
		System.out.println("localDateTime : " + dateFormat8.format(localDateTime));

		localDateTime = localDateTime.minusYears(2);
		localDateTime = localDateTime.minusMonths(2);
		localDateTime = localDateTime.minusDays(2);

		localDateTime = localDateTime.minusHours(2).minusMinutes(2).minusSeconds(2);

		// converting LocalDateTime to Date
		Date currentDateminus = Date.from(localDateTime.atZone(ZoneId.systemDefault()).toInstant());

		// printing the new date
		String newDateinStr = dateFormat.format(currentDateminus);
		System.out.println("New date after going back 2 years : " + newDateinStr);

	}
}

Output:

Current date : 2020-11-16 03:04:00
localDateTime : 2020-11-16 03:04:00
New date after going back 2 years : 2018-09-14 01:01:58

4. Conclusion

In this quick article, you've learnt how to increment or decrement the date in old java and new java 8 Date time api.

GitHub

AddDaysExample

Java8AddDaysExample

Java8MinusDaysExample

Read next:

How to convert Calendar to LocalDateTime in java 8?

How to increment or decrement date time using joda date time?

How to calculate days between two days in java 8?

How to compare two dates in java 8 ?