How to Format Time in 24 Hour Format using Java

Formatting time in a 24-hour format can be achieved by using the SimpleDateFormat class in Java. By specifying the correct pattern, we can display the time in a 24-hour format like "HH:mm:ss".

Displaying Hour in 24-hour Format

SimpleDateFormat: SimpleDateFormat is a concrete class for formatting and parsing dates in a locale-sensitive manner. SimpleDateFormat allows you to start by choosing any user-defined patterns for date-time formatting.

Date class: The Java Util Date class represents a specific instant in time, with millisecond precision.

Syntax

Here is the syntax of java.util.Date class constructor:

public class Date
   extends Object
   implements Serializable, Cloneable, Comparable<Date>

We will use the SimpleDateFormat class to display the hour in 24-hour format (HH). The format() method converts the current time into the desired format.

Example

The following example formats the time into 24 hour format (00:00-24:00) by using sdf.format(date) method of SimpleDateFormat class.

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

public class Main {
   public static void main(String[] args) {
      Date date = new Date();
      SimpleDateFormat sdf = new SimpleDateFormat("h");
      System.out.println("hour in h format : " + sdf.format(date));
   }
}

Output

hour in h format : 8

Displaying Time in 24-hour Format (hh:mm:ss)

We will formats the current time to display the hour, minute, and second in a 24-hour format using the HH:mm:ss pattern. It will output something like 06:04:26 based on the current system time.

Example

The following is another example of date and time

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

public class Main { 
   public static void main(String[] argv) throws Exception {
      Date d = new Date();
      SimpleDateFormat simpDate;
      simpDate = new SimpleDateFormat("hh:mm:ss");
      System.out.println(simpDate.format(d));
   }
}

Output

05:40:36