Refactoring method with Optional to one line [closed]

I have a method in my Service for updating existing organisations.

public Optional<Organisation> update(Organisation org) {
    Optional<Organisation> optionalOrganisation = organisationRepository.findById(org.getId());
    if (optionalOrganisation.isPresent()) {
        Organisation organisationToUpdate = optionalOrganisation.get();
        organisationRepository.save(organisationToUpdate);
    }
    return Optional.empty();
}

How to refactor this method to one line?

It should be something like this:

public Optional<Organisation> update(Organisation org) {
    return organisationRepository.findById(org.getId()) // what should be here?

Answer

This is what I was looking for:

public Optional<Organisation> update(Organisation org) {
    return organisationRepository.findById(org.getId())
            .map(organisationRepository::save);
}