The withZoneSameInstant() method of a ZonedDateTime class is used to return a copy of this ZonedDateTime object by changing the time-zone and without the instant. This method is based on retaining the same instant, thus gaps and overlaps in the local timeline have no effect on the result.
Syntax:
public ZonedDateTime withZoneSameInstant(ZoneId zone)
Parameters: This method accepts one single parameter zone the time-zone to change to. It should not be null.
Return value: This method returns a ZonedDateTime based on this date-time with the requested zone.
Exception Thrown: DateTimeException if the result exceeds the supported date range.
Example 1:
Java
// Java program to demonstrate// ZonedDateTime.withZoneSameInstant() methodÂ
// Importing required classesimport java.time.*;Â
// Main classpublic class GFG {Â
    // Main driver method    public static void main(String[] args)    {        // Creating a ZonedDateTime object        ZonedDateTime zonedDT = ZonedDateTime.parse(            "2018-12-06T19:21:12.123+05:30[Asia/Calcutta]");Â
        // Printing ZonedDateTime of Calcutta on console        System.out.println("ZonedDateTime of Calcutta: "                           + zonedDT);Â
        // Applying withZoneSameInstant()        ZonedDateTime zonedDT2            = zonedDT.withZoneSameInstant(                ZoneId.of("Pacific/Fiji"));Â
        // Now printing ZonedDateTime of Fuji        // after withZoneSameInstant()        System.out.println("ZonedDateTime of Fuji: "                           + zonedDT2);    }} |
Output:Â
ZonedDateTime of Calcutta: 2018-12-06T19:21:12.123+05:30[Asia/Calcutta] ZonedDateTime of Fuji: 2018-12-07T02:51:12.123+13:00[Pacific/Fiji]
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Example 2:
Java
// Java program to Demonstrate// ZonedDateTime.withZoneSameInstant() methodÂ
// Importing required classesimport java.time.*;Â
// Main classpublic class GFG {Â
    // Main driver method    public static void main(String[] args)    {        // Creating a ZonedDateTime object and        // passing date and time of Europe/Paris        ZonedDateTime zonedDT = ZonedDateTime.parse(            "2018-10-25T23:12:31.123+02:00[Europe/Paris]");Â
        // Printing ZonedDateTime of Paris on console        // before applying withZoneSameInstant() method        System.out.println("ZonedDateTime of Paris: "                           + zonedDT);Â
        // Now applying withZoneSameInstant() method        ZonedDateTime zonedDT2            = zonedDT.withZoneSameInstant(                ZoneId.of("Canada/Yukon"));Â
        // Printing ZonedDateTime        // after applying withZoneSameInstant()        System.out.println("ZonedDateTime of Yukon: "                           + zonedDT2);    }} |
Output
ZonedDateTime of Paris: 2018-10-25T23:12:31.123+02:00[Europe/Paris] ZonedDateTime of Yukon: 2018-10-25T14:12:31.123-07:00[Canada/Yukon]
