reduce

package test;

import static java.time.temporal.ChronoUnit.MILLIS;

import java.time.LocalDateTime;
import java.util.List;
import java.util.Optional;

public class Test {
    public static void main(String[] args) {
        System.out.println(new Test().getClosest("123", LocalDateTime.now()
            .plusMinutes(0)));
    }

    private Optional<Dummy> getClosest(String id, LocalDateTime time) {
        List<Dummy> list = List.of(new Dummy(LocalDateTime.now(), "123", "1"),
                                   new Dummy(LocalDateTime.now()
                                       .plusMinutes(4), "123", "2"),
                                   new Dummy(LocalDateTime.now()
                                       .plusMinutes(42), "123", "22"));
        return list.stream()
            .filter(dummy -> dummy.id.equals(id))
            .reduce((result, current) -> Math.abs(MILLIS.between(time, current.getTime())) < Math.abs(MILLIS.between(time, result.getTime())) ? current : result);
    }

    public static class Dummy {
        final LocalDateTime time;
        final String id;
        final String title;

        public Dummy(LocalDateTime time, String id, String title) {
            this.time = time;
            this.id = id;
            this.title = title;
        }

        public LocalDateTime getTime() {
            return time;
        }

        public String getId() {
            return id;
        }

        @Override
        public String toString() {
            return time.toString() + " " + title;
        }
    }

}