Date & Time in Java

Working with dates and times is something you'll commonly need in real Java programs. For example, you may want to display today's date, get the current time, calculate the difference between two dates, or format a date in a particular way.

Java provides several classes for working with date and time. In modern Java programs, the java.time package is generally the preferred choice.

Getting the Current Date

We can use LocalDate to represent a date without a time.

First, import it:

import java.time.LocalDate;

Then:

LocalDate today = LocalDate.now();

System.out.println(today);

The output will look something like:

2026-08-22

The exact date depends on when the program is executed.

LocalDate stores information such as:

Year
Month
Day

but it does not contain a time.

Getting the Current Time

For a time without a date, we can use LocalTime.

import java.time.LocalTime;

LocalTime time = LocalTime.now();

System.out.println(time);

The output might look like:

10:30:45.123456789

The exact value will depend on the current time.

LocalTime stores information such as hours, minutes, seconds, and nanoseconds.

Getting the Current Date and Time

If we need both the date and time, we can use LocalDateTime.

import java.time.LocalDateTime;

LocalDateTime now = LocalDateTime.now();

System.out.println(now);

Output might look like:

2026-08-22T10:30:45.123

Here, T separates the date from the time.

Creating a Specific Date

We don't always need the current date. We can create a specific date using of().

import java.time.LocalDate;

LocalDate birthday = LocalDate.of(2000, 5, 15);

System.out.println(birthday);

Output:

2000-05-15

The values represent:

Year → 2000
Month → 5
Day → 15

Getting Individual Parts of a Date

We can get the year, month, and day separately.

LocalDate date = LocalDate.of(2026, 8, 22);

System.out.println(date.getYear());
System.out.println(date.getMonth());
System.out.println(date.getDayOfMonth());

Output:

2026
AUGUST
22

We can also get the month as a number:

System.out.println(date.getMonthValue());

Output:

8

Adding and Subtracting Time

Java makes it easy to calculate new dates.

For example:

LocalDate today = LocalDate.now();

LocalDate nextWeek = today.plusDays(7);

System.out.println(nextWeek);

We can also add months or years:

LocalDate date = LocalDate.now();

System.out.println(date.plusMonths(2));
System.out.println(date.plusYears(1));

Similarly, we can subtract time:

LocalDate previousWeek = today.minusDays(7);

This is useful when working with things such as deadlines, appointments, subscriptions, and schedules.

Comparing Dates

We can compare dates using methods such as isBefore(), isAfter(), and isEqual().

For example:

LocalDate date1 = LocalDate.of(2026, 8, 20);
LocalDate date2 = LocalDate.of(2026, 8, 25);

System.out.println(date1.isBefore(date2));
System.out.println(date1.isAfter(date2));

Output:

true
false

We can also check whether two dates are equal:

System.out.println(date1.isEqual(date2));

Formatting Dates

By default, Java displays dates in a format like:

2026-08-22

Sometimes we want a different format, such as:

22/08/2026

For this, we can use DateTimeFormatter.

import java.time.LocalDate;
import java.time.format.DateTimeFormatter;

LocalDate date = LocalDate.now();

DateTimeFormatter formatter =
        DateTimeFormatter.ofPattern("dd/MM/yyyy");

String formattedDate = date.format(formatter);

System.out.println(formattedDate);

Output:

22/08/2026

Here:

dd → day
MM → month
yyyy → year

We can create other formats as well.

For example:

DateTimeFormatter formatter =
        DateTimeFormatter.ofPattern("dd MMM yyyy");

This could produce:

22 Aug 2026

Calculating the Difference Between Dates

Java also provides Period for calculating the difference between two dates.

For example:

import java.time.LocalDate;
import java.time.Period;

LocalDate start = LocalDate.of(2020, 1, 1);
LocalDate end = LocalDate.of(2026, 1, 1);

Period difference = Period.between(start, end);

System.out.println(difference.getYears());

Output:

6

This is useful for things such as calculating someone's age or the period between two dates.

Date and Time Classes

The java.time package contains several useful classes.

The most important ones to know initially are:

For example, if you're building an application for users in different countries, ZonedDateTime becomes useful because the time zone matters.

A Complete Example

Let's create a simple program that displays today's date and calculates a date one week from now:

import java.time.LocalDate;
import java.time.format.DateTimeFormatter;

class Main {
    public static void main(String[] args) {

        LocalDate today = LocalDate.now();

        DateTimeFormatter formatter =
                DateTimeFormatter.ofPattern("dd MMM yyyy");

        System.out.println("Today: " + today.format(formatter));

        LocalDate nextWeek = today.plusDays(7);

        System.out.println(
                "Next week: " + nextWeek.format(formatter)
        );
    }
}

The output will depend on the date when you run the program, but it will look something like:

Today: 22 Aug 2026
Next week: 29 Aug 2026

The main thing to remember is that modern Java provides the java.time package for working with dates and times. The classes you'll use most often at the beginning are LocalDate, LocalTime, LocalDateTime, and DateTimeFormatter.