Clock.php

<?php

declare (strict_types=1);
namespace OpenTelemetry\API\Common\Time;

final class Clock {
    private static ?ClockInterface $clock = null;
    public static function getDefault() : ClockInterface {
        return self::$clock ??= new SystemClock();
    }
    public static function setDefault(ClockInterface $clock) : void {
        self::$clock = $clock;
    }
    public static function reset() : void {
        self::$clock = null;
    }

}