Date.from(Instant) in Java

Date.from(Instant): This method is available in java.util.Date class of Java.

Syntax:

Date java.util.Date.from(Instant instant)

This method takes one argument of type Instant as its parameter. This method obtains an instance of Date from an Instant object.

Note: Instant uses a precision of nanoseconds, whereas Dateuses a precision of milliseconds.

Parameters: One parameter is required for this method.

instant: the instant to convert.

Returns: a Date representing the same point on the timeline as the provided instant.

Throws:

1. NullPointerException - if instant is null.

2. IllegalArgumentException - if the instant is too large to represent as a Date.

Approach 1: When no exception

Java

import java.time.Instant;
import java.util.Date;

public class Datefrom {
    public static void main(String[] args) {

        Date date = new Date();

        Instant instant = date.toInstant();
        System.out.println(Date.from(instant));

    }
}

Output:

Sun Jan 30 18:01:46 IST 2022

Approach 2: NullPointerException 

Java

import java.time.Instant;
import java.util.Date;

public class Datefrom {
    public static void main(String[] args) {

        Instant instant = null;
        System.out.println(Date.from(instant));

    }
}

Output:

Exception in thread "main" java.lang.NullPointerException: Cannot invoke "java.time.Instant.toEpochMilli()" because "instant" is null
	at java.base/java.util.Date.from(Date.java:1363)