ChronoZonedDateTime until() method in Java with Examples

The until() method of the ChronoZonedDateTime interface used to calculate the amount of time between two ChronoZonedDateTime objects using TemporalUnit. The start and end points are this and the specified ChronoZonedDateTime 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 ChronoZonedDateTime. This instance is immutable and unaffected by this method call.

Syntax:

long until(Temporal endExclusive, TemporalUnit unit)

Parameters: This method accepts two parameters:

endExclusive: which is the end date, exclusive, which is converted to a ChronoZonedDateTime
unit: which is the unit to measure the amount.

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

Exception:This method throws following Exceptions:

DateTimeException – if the amount cannot be calculated, or the ending temporal cannot be converted to a ChronoZonedDateTime.
UnsupportedTemporalTypeException – if the unit is not supported.
ArithmeticException – if numeric overflow occurs.

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

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

import java.time.*; 

import java.time.chrono.*; 

import java.time.temporal.*; 

public class GFG { 

    public static void main(String[] args) 

    { 

        // create ChronoZonedDateTime objects 

        ChronoZonedDateTime z1 

            = ZonedDateTime 

                  .parse( 

                      "2018-12-06T19:21:12.123+05:30[Asia/Calcutta]"); 

        ChronoZonedDateTime z2 

            = ZonedDateTime 

                  .parse( 

                      "2018-10-25T23:12:31.123+02:00[Europe/Paris]"); 

        // apply until method of ChronoZonedDateTime class 

        long result 

            = z1.until(z2, 

                       ChronoUnit.HOURS); 

        // print results 

        System.out.println("Result in HOURS: "

                           + result); 

    } 
}

Output:

Result in HOURS: -1000

Program 2:

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

import java.time.*; 

import java.time.chrono.*; 

import java.time.temporal.*; 

public class GFG { 

    public static void main(String[] args) 

    { 

        // create ChronoZonedDateTime objects 

        ChronoZonedDateTime z1 

            = ZonedDateTime 

                  .parse( 

                      "2018-12-06T19:21:12.123+05:30[Asia/Calcutta]"); 

        ChronoZonedDateTime z2 

            = ZonedDateTime 

                  .parse( 

                      "2018-10-25T23:12:31.123+02:00[Europe/Paris]"); 

        // applynedDateTime.parseChronoZonedDateTime class 

        long result 

            = z2.until(z1, 

                       ChronoUnit.DAYS); 

        // print results 

        System.out.println("Result in DAYS: "

                           + result); 

    } 
}