The toNanoOfDay() method of LocalTime class is used to return the time as nanos of day from this LocalTime.Value returned by this method lie between 0 to 24 * 60 * 60 * 1, 000, 000, 000 – 1.
Syntax:
public long toNanoOfDay()
Parameters: This method accepts no parameters.
Return value: This method returns a long value which is the nano of day value and is equivalent to this time.
Below programs illustrate the toNanoOfDay() method:
Program 1:
Java
// Java program to demonstrate// LocalTime.toNanoOfDay() methodimport java.time.*;public class GFG {    public static void main(String[] args)    {        // create a LocalTime object        LocalTime time            = LocalTime.parse("19:34:50.63");        // extract nano of day from toNanoOfDay()        long value = time.toNanoOfDay();        // print result        System.out.println("Nano of day: "                           + value);    }} | 
Nano of day: 70490630000000
Program 2:
Java
// Java program to demonstrate// LocalTime.toNanoOfDay() methodimport java.time.*;public class GFG {    public static void main(String[] args)    {        // create a LocalTime object        LocalTime time            = LocalTime.parse("23:21:45.98");        // extract nano of day from toNanoOfDay()        long value = time.toNanoOfDay();        // print result        System.out.println("Nano of day: "                           + value);    }} | 
Nano of day: 84105980000000
Reference: https://docs.oracle.com/javase/10/docs/api/java/time/LocalTime.html#toNanoOfDay()
