Java <Optional> Object is null or object's property is null?

Question

I would like to migrate this legacy Java example code to Java 8.

public String getUserSex(Person person) {
    if(person != null) {
        if(person.getSex() != null) {
            return person.getSex();
        }
    }

    return null;
}  

How to migrate this to Java 8 using Optional?

Answer 1

Use Optional.ofNullable and Optional.flatMap

public Optional<String> getUserSex(Person person)
{
    return Optional.ofNullable(person).flatMap(
        p -> Optional.ofNullable(p.getSex())
    );
}