.computeFields()

The .computeFields() method of the Calendar class converts the current millisecond time value to the relevant field values in the Calendar object.

Syntax

calendar.computeFields()

Note: computeFields() method is a non-static method, it is accessible with the Calendar instance. Trying to access it with the class name throws an error.

Example

In the example below the CalendarComputeFieldExample class is instantiated and the calendar is set to the year 2024. Then, the computeFields() method is called to sync up the Calendar field values with the new time that has been set for the Calendar object.

import java.util.*;

public class CalendarComputeFieldExample extends GregorianCalendar {
 public static void main(String[] args) {
  // Instantiate a new Calendar object
  CalendarComputeFieldExample cal = new CalendarComputeFieldExample();

  // Print the current date
  System.out.println("Current date is: " + cal.getTime());

  // Clear the calendar
  cal.clear();

  // Set a new year and call computeFields()
  cal.set(GregorianCalendar.YEAR, 2024);
  System.out.println("New date is: " + cal.getTime());
  cal.computeFields();

  // Print the current date
  System.out.println("New date is: " + cal.getTime());
  }
}

This results in the following output:

Current date is: Fri Aug 18 20:54:51 GMT 2023
New date is: Mon Jan 01 00:00:00 GMT 2024
New date is: Mon Jan 01 00:00:00 GMT 2024