LocalTime toEpochSecond() method in Java with Examples

The toEpochSecond() method of LocalTime class is used to convert this LocalTime to the number of seconds since the epoch of 1970-01-01T00:00:00Z. The method combines this local time with the specified date and offset passed as parameters to calculate the epoch-second value, which is the number of elapsed seconds from 1970-01-01T00:00:00Z. Instants on the timeline after the epoch are positive, earlier are negative.

Syntax:

public long 
         toEpochSecond(LocalDate date,
                          ZoneOffset offset)

Parameters: This method accepts two parameters:

• date: It is the date which is to be used for epoch second calculation as the target date.
• offset: It is the zone offset.

Return value: This method returns number of seconds since the epoch of 1970-01-01T00:00:00Z. It may be negative.

Below programs illustrate the toEpochSecond() method:

Program 1:

// Java program to demonstrate
// LocalTime.toEpochSecond() method

import java.time.*;

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

        // create a LocalDate object
        LocalDate date
            = LocalDate.parse("2018-12-29");

        // create a LocalTime object
        LocalTime time
            = LocalTime.parse("20:12:32");

        // print Instant
        System.out.println("LocalDate: " + date);

        // create ZoneId
        ZoneOffset zone = ZoneOffset.of("Z");

        // print ZoneId
        System.out.println("ZoneOffset: " + zone);

        // apply ofInstant()
        long value = time.toEpochSecond(date, zone);

        // print result
        System.out.println("Epoch Second: "
                           + value);
    }
}

Output:

LocalDate: 2018-12-29
ZoneOffset: Z
Epoch Second: 1546114352

Program 2:

// Java program to demonstrate
// LocalTime.toEpochSecond() method

import java.time.*;

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

        // create a LocalDate object
        LocalDate date
            = LocalDate.parse("1909-04-18");

        // create a LocalTime object
        LocalTime time
            = LocalTime.parse("00:10:09");

        // print Instant
        System.out.println("LocalDate: " + date);

        // create ZoneId
        ZoneOffset zone = ZoneOffset.of("Z");

        // print ZoneId
        System.out.println("ZoneOffset: " + zone);

        // apply ofInstant()
        long value = time.toEpochSecond(date, zone);

        // print result
        System.out.println("Epoch Second: "
                           + value);
    }
}

Output:

LocalDate: 1909-04-18
ZoneOffset: Z
Epoch Second: -1915746591

References: https://docs.oracle.com/javase/10/docs/api/java/time/LocalTime.html#toEpochSecond(java.time.LocalDate, java.time.ZoneOffset)