Change File Last Modified date in Java example

In this example we are going to see how you can change the “Last Modified” date of a File in your File System in Java. We are simply going to use the setLastModified method of the File class. We are also going to see how you can parse a string with a date format to a Date object which is kind of cool.

So the basic steps to change the “Last Modified” date of file in Java are:

• Use the SimpleDateFormat("MM/dd/yyyy") constructor to make a new SimpleDateFormat class instance.
• Construct a String object with the “MM/dd/yyyy” format.
• Use parse(String date) method of the SimpleDateFormat class to create a new Date object with the date value of the String.
• Use File.setLastModified(Date.getTime()) method to set the new “Last Modified” date of the file.

Let’s see the code:

package com.javacodegeeks.java.core;

import java.io.File;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;

public class ChangeFileLastModifiedDate {

	public static final String filepath = "/home/nikos/Desktop/testFile.txt";

	public static void main(String[] args) {
		try {

			File file = new File(filepath);

			SimpleDateFormat dateFormat = new SimpleDateFormat("MM/dd/yyyy");

			// print the original Last Modified date
			System.out.println("Original Last Modified Date : "
					+ dateFormat.format(file.lastModified()));

			// set this date
			String newLastModifiedString = "01/31/1821";

			// we have to convert the above date to milliseconds...
			Date newLastModifiedDate = dateFormat.parse(newLastModifiedString);
			file.setLastModified(newLastModifiedDate.getTime());

			// print the new Last Modified date
			System.out.println("Lastest Last Modified Date : "
					+ dateFormat.format(file.lastModified()));

		} catch (ParseException e) {

			e.printStackTrace();

		}

	}

}

Output:

Original Last Modified Date : 02/21/2013
New Last Modified Date : 02/02/2000

 
This was an example on how to change the Last Modified date value of a File in your File System in Java.