The method java.time.Clock.system(ZoneId zone) a clock that uses the best available system clock in the specified zone – never null.

The signature of the java.time.Clock.system(ZoneId zone) method is as follows:

public static Clock system(ZoneId zone)

The method is available since Java 8.

• ZoneId zone: the time-zone that will be used to convert the instant to date-time, not null.

Returns a clock that uses the best available system clock in the specified zone, never null.

The method throws no exceptions.

In the following code we use java.time.Clock.system(ZoneId zone):

package com.farenda.java.time;

import java.time.Clock;
import java.time.ZoneId;
import java.util.Date;
import java.util.concurrent.TimeUnit;

public class ClockExample {

    public static void main(String[] args) {
        Date now = new Date();
        System.out.println("Current date: " + now);

        ZoneId centralEurope = ZoneId.of("Europe/Warsaw");
        Clock clock = Clock.system(centralEurope);
        System.out.println("From clock: "
                + new Date(clock.millis()));

        try {
            // wait for a while:
            TimeUnit.SECONDS.sleep(1);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }

        System.out.println("Second later: "
                + new Date(clock.millis()));
    }
}

The above code produces the following output:

Current date: Sat May 21 10:41:26 CEST 2016
From clock: Sat May 21 10:41:26 CEST 2016
Second later: Sat May 21 10:41:27 CEST 2016

• Compare with Fixed Clock behavior