Java program to display previous month from GregorianCalendar

The GregorianCalendar class in Java allows us to manipulate dates and times easily. In this example, we will create a GregorianCalendar object and use it to display the current date and the date of the previous month.

Problem Statement

Write a Java program and create a GregorianCalendar object, display the current date, and then modify this date to show the date of the previous month.

Output

Current date: Mon Nov 19 18:07:03 UTC 2018

Input

Modified date (Previous Month): Fri Oct 19 18:07:03 UTC 2018

Steps to display previous month from GregorianCalendar

Below are the steps to display previous month from GregorianCalendar ?

• Import the necessary packages.
• Create a GregorianCalendar object using GregorianCalendar.getInstance().
• Display the current date.
• Use the add() method with the MONTH field and a value of -1 to subtract one month from the current date.
• Display the modified date.

Java program to display previous month from GregorianCalendar

import java.util.Calendar;    
import java.util.GregorianCalendar;
public class Demo {
 public static void main(String[] a) {
GregorianCalendar cal = (GregorianCalendar) GregorianCalendar.getInstance();
System.out.println("Current date: " + cal.getTime());
// past month
cal.add((GregorianCalendar.MONTH), -1);
System.out.println("Modified date (Previous Month): " + cal.getTime());
 }
}

Output

Current date: Mon Nov 19 18:07:03 UTC 2018
Modified date (Previous Month): Fri Oct 19 18:07:03 UTC 2018

Code Explanation

Initially, we will import the GregorianCalender class and Calender class from java.util package.

import java.util.GregorianCalendar;

We create a GregorianCalendar object named cal using GregorianCalendar.getInstance(), which initializes it to the current date and time.

GregorianCalendar cal = (GregorianCalendar) GregorianCalendar.getInstance();

Now, use the following field and add() method with a negative one -1 to display the previous month.

cal.add((GregorianCalendar.MONTH), -1)

Finally, we print the modified date to show the date of the previous month.