How to change the file last modified date in Java?

Question:

How to change the file last modified date in Java?

Answer:

Use File.setLastModified()

Code:

import java.io.*;
import java.util.*;
import java.text.*;
 
public class ChangeModificationTime {
   public static void main(String[] args) {
      File file = new File("ChangeModificationTime.java");
 
      Date date = new Date(file.lastModified());
      System.out.println(date);
 
      try {
         String str = "01/31/1998";
         SimpleDateFormat sdf = new SimpleDateFormat("MM/dd/yyyy");
         Date newDate = sdf.parse(str);
         file.setLastModified(newDate.getTime());
      } catch(ParseException e) {
         System.out.println("ParseException");
      }
 
      date = new Date(file.lastModified());
      System.out.println(date);
 
   }
}

Output:

$ ls -l ChangeModificationTime.java 
-rw-rw-r-- 1 dennis dennis 664 Feb 26 12:44 ChangeModificationTime.java

$ java ChangeModificationTime
Thu Feb 26 12:44:31 EST 2015
Sat Jan 31 00:00:00 EST 1998

$ ls -l ChangeModificationTime.java 
-rw-rw-r-- 1 dennis dennis 664 Jan 31  1998 ChangeModificationTime.java