Find first non-repeating character from a String

import java.util.LinkedHashMap;
import java.util.Optional;
import java.util.stream.Collectors;

import static java.util.function.Function.identity;

public class Utils {

    private Optional<Character> findFirstNonRepeatingLetter(String s) {
        final Optional<Character> optionalCharacter = s.chars()
                .mapToObj(i -> (char) i)
                .collect(Collectors.groupingBy(identity(), LinkedHashMap::new, Collectors.counting()))
                .entrySet().stream()
                .filter(entry -> entry.getValue() == 1L)
                .map(entry -> entry.getKey())
                .findFirst();
        return optionalCharacter;
    }
}