var someOptional = Optional.ofNullable("Something");
if (someOptional.isPresent()) { // same structure as without Optinal API, actually only a bit more verbose
    System.out.println(someOptional.get().toUpperCase());
} else {
    System.out.println("");
}

var text = Optional.ofNullable("Something") //
.map(String::toUpperCase) // this line is only executed if the optional value is present
.orElse("");
System.out.println(text);