Java Enum.valueOf() efficiency when value does not exist

Question

Which would you consider more efficient?

The use of \'WeekDay\' is just an example:

public enum WeekDay {
    MONDAY, TUESDAY, WEDNESDAY, THURSDAY, FRIDA         


        

Answer 1

The loop doesn't do anything that calling valueof doesn't, they have the same functionality : checking whether your string is valid enum. What do you think you gain from the first option ?

The second option is best:

 try {
     WeekDay weekDay = WeekDay.valueOf(day); // might throw exception
        ...
    } catch (IllegalArgumentException e) {
        throw new InvalidWeekDayException(day);
    }