import java.time.Instant;
import java.time.ZoneId;
import java.time.zone.ZoneOffsetTransition;

public class Main {
	public static void main(String[] args) {
		ZoneId zoneId = ZoneId.of("Europe/London");
		ZoneOffsetTransition nextTransition = zoneId.getRules().previousTransition(Instant.now());
		System.out.println("Local date-time before the transition: " + nextTransition.getDateTimeBefore());
		System.out.println("Zone offset before the transition: " + nextTransition.getOffsetBefore());
	}
}