Instant from() method in Java with Examples

The from() method of Instant class helps to get instance of instant from TemporalAccessor object passed as parameter. A TemporalAccessor represents an arbitrary set of date and time information and this method helps to get an instant based on the specified TemporalAccessor object. The conversion of TemporalAccessor object to instant extracts the INSTANT_SECONDS and NANO_OF_SECOND fields. Syntax:

public static Instant
    from(TemporalAccessor temporal)

Parameters: This method accepts only one parameter temporal which represents the temporal object. It should not be null. Returns: This method returns Instant object from the TemporalAccessor Object. It should not be null. Exception: This method throws DateTimeException if method is unable to convert temporal object to an Instant. Below programs illustrate the from() method: Program 1:

Java

// Java program to demonstrate
// Instant.from() method

import java.time.*;

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

        // create a ZonedDateTime object
        ZonedDateTime zonedDateTime
            = ZonedDateTime.now();

        // print Value
        System.out.println("ZonedDateTime: "
                           + zonedDateTime);

        // create a Instant object using
        // from() method
        Instant result = Instant.from(zonedDateTime);

        // print result
        System.out.println("Instant: "
                           + result);
    }
}

Output:

ZonedDateTime: 2018-11-27T04:58:47.691Z[Etc/UTC]
Instant: 2018-11-27T04:58:47.691Z

Program 2:

Java

// Java program to demonstrate
// Instant.from() method

import java.time.*;

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

        // create a OffsetDateTime object
        OffsetDateTime offset
            = OffsetDateTime.now();

        // print Value
        System.out.println("OffsetDateTime: "
                           + offset);

        // apply from() method
        Instant result = Instant.from(offset);

        // print result
        System.out.println("Instant: "
                           + result);
    }
}

Output:

OffsetDateTime: 2018-11-27T04:58:50.588Z
Instant: 2018-11-27T04:58:50.588Z

References: https://docs.oracle.com/javase/10/docs/api/java/time/Instant.html#from(java.time.temporal.TemporalAccessor)