Instant until() Method in Java with Examples

until() method of an Instant class used to calculate the amount of time between two Instant objects using TemporalUnit. The start and end points are this and the specified instant passed as a parameter. The result will be negative if the end is before the start. The calculation returns a whole number, representing the number of complete units between the two instants. This instance is immutable and unaffected by this method call.

Syntax:

public long until(Temporal endExclusive, TemporalUnit unit)

Parameters: This method accepts two parameters endExclusive which is the end date, exclusive, which is converted to an Instant and unit which is the unit to measure the amount.

Return value: This method returns the amount of time between this instant and the end instant.

Exception:This method throws following Exceptions:

• DateTimeException – if the amount cannot be calculated, or the end temporal cannot be converted to an Instant.
• UnsupportedTemporalTypeException – if the unit is not supported.
• ArithmeticException – if numeric overflow occurs.

Below programs illustrate the until() method:
Program 1:

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

import java.time.*;
import java.time.temporal.ChronoUnit;

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

        // create Instant objects
        Instant instant1
            = Instant.parse("2019-01-03T19:35:50.00Z");
        Instant instant2
            = Instant.parse("2019-01-04T13:18:59.00Z");

        // apply until method of Instant class
        long result
            = instant1.until(instant2,
                             ChronoUnit.MINUTES);

        // print results
        System.out.println("Result in Minutes: "
                           + result);
    }
}

Output:

Result in Minutes: 1063

Program 2:

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

import java.time.*;
import java.time.temporal.ChronoUnit;

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

        // create Instant objects
        Instant instant1
            = Instant.parse("2010-01-03T19:35:50.00Z");
        Instant instant2
            = Instant.parse("2019-01-04T13:18:59.00Z");

        // apply until method of Instant class
        long result
            = instant1.until(instant2,
                             ChronoUnit.DAYS);

        // print results
        System.out.println("Result in DAYS: "
                           + result);
    }
}

Output:

Result in DAYS: 3287

References:
https://docs.oracle.com/javase/10/docs/api/java/time/Instant.html#until(java.time.temporal.Temporal, java.time.temporal.TemporalUnit)