Convert Milliseconds to Date in Java

In Java, usually we need to convert milliseconds into the Date of different format such as dd MMM yyyy and dd MMM yyyy HH:mm:ss:SSS Z, etc.

The Date is one of the most important class in Java to work with Date. It internally stores the Date in milliseconds. By using the constructor of the Date class, we can create a Date from milliseconds.

Before proceeding further, it is required to gain knowledge of the SimpleDateFormat class. It is one of the classes that we use to format and parse data. It helps us to convert a date from one format into another one. It is also helpful in converting a date of string format into a date object. In simple words, the SimpleDateFormat class is used for modifying Date accordingly.

Let's take some examples to understand how we can convert milliseconds to Date.

MillisecondsToDateExample1.java

// import required classes and packages  
package javaTpoint.javacodes; 
import java.text.DateFormat; 
import java.text.SimpleDateFormat; 
import java.util.Date; 
import java.util.Scanner; 
// create MillisecondsToDateExample1 class to convert milliseconds into Date 
public class MillisecondsToDateExample1 { 
// main() method start 
public static void main(String args[]) 
{ 
	// declaration of a variable for milliseconds 
		long miliSec; 
		// create scanner class object 
	Scanner sc = new Scanner(System.in);   
        		System.out.print("Enter milliseconds: ");   
        		// take input from user and initialize variable  
       		 miliSec = sc.nextLong();   
        		// close scanner class obj 
       		 sc.close(); 
       		 // create an instance of the SimpleDateFormat class for modifying the date object 
       		 DateFormat obj = new SimpleDateFormat("dd MMM yyyy HH:mm:ss:SSS Z"); 
        		// we create instance of the Date and pass milliseconds to the constructor  
        		Date res = new Date(miliSec); 
        		// now we format the res by using SimpleDateFormat 
        		System.out.println(obj.format(res)); 
} 
} 

Output:

MillisecondsToDateExample2.java

// import required classes and package 
package javaTpoint.javacodes; 
import java.text.DateFormat; 
import java.text.SimpleDateFormat; 
import java.util.Calendar; 
import java.util.Date; 
//create MillisecondsToDateExample2 class to convert milliseconds into Date 
public class MillisecondsToDateExample2 { 
// main() method start 
    public static void main(String args[]) { 
       //use currentTimeMillis() method of system to get current time in milliseconds 
       long milliSec = System.currentTimeMillis(); 
       //convert milliseconds into Date by creating an object of the date class and passing milliseconds to the constructor 
       Date res = new Date(milliSec); 
       //printing value of Date(default format) 
       System.out.println("After converting milliseconds into date: " + res); 
       // create an instance of the SimpleDateFormat class for modifying date object into dd:MM:yy:HH:mm:ss and dd MMM yyyy HH:mm:ss:SSS Z format 
       DateFormat sdf1 = new SimpleDateFormat("dd:MM:yy:HH:mm:ss"); 
       DateFormat sdf2 = new SimpleDateFormat("dd MMM yyyy HH:mm:ss:SSS Z"); 
       //after formatting the res into dd:MM:yy:HH:mm:ss and dd MMM yyyy HH:mm:ss:SSS Z format 
       System.out.println("Date in dd:MM:yy:HH:mm:ss: " + sdf1.format(res)); 
       System.out.println("Date in dd MMM yyyy HH:mm:ss:SSS Z: " + sdf2.format(res)); 
       //convert milliseconds into Date by using calendar class 
       // create instance of the Calendar class 
       Calendar calndr = Calendar.getInstance(); 
       // use setTimeInMillis() method od the calendar class to set time  
       calndr.setTimeInMillis(milliSec); 
       // after formatting the date into dd:MM:yy:HH:mm:ss 
       System.out.println("After converting milliseconds into date using Calendar class: "+ sdf1.format(calndr.getTime())); 
       //copying data of one date into another one 
       Date currentdate = new Date(); 
       Date tempDate = new Date(currentdate.getTime()); 
       System.out.println("original Date: " + sdf1.format(currentdate)); 
       System.out.println("copied Date: " + sdf1.format(tempDate)); 
    } 
} 

Output: