4 ms·

With proper OO you could still implement that on the user object. boolean isAdult() { return this.age >= this.location.ageOfAdulthood(); /

• Terr_ 2y ago
  Just having some fun with bikeshedding here: Yeah, that could work but IMO in a big/international system the responsibility should ideally live elsewhere, since: * You may need to determine adulthood for a different jurisdiction than where the person currently resides. Their citizenship may be elsewhere, or you may be running a report that expects "adulthood" to be by some other region's standards, etc. * Sometimes the underlying kind of adult-need wanted is slightly different, like for consuming alcohol or voting. * There may be a weird country or province has laws that need additional factors, like some odd place where it's a different age-cutoff for men and women.
  • vips7L 2y ago
    Yes this is just extreme bike-shedding at this point. But none of this is impossible with more OO principles, like interfaces: class User { // Convenience function to check if the user is an adult in their current location boolean isAdult() { return this.location.isAdult(this); } boolean isOfDrinkingAge() { return this.location.isOfDrinkingAge(this); } } interface Location { boolean isAdult(User u); boolean isOfDrinkingAge(User u); } class WeirdLawsLocation implements Location { boolean isAdult(User u) { return switch (u.gender()) { case MALE -> u.age() >= 16; case FEMALE -> u.age() >= 18; } } boolean isOfDrinkingAge(User u) { return u.age() >= 21 } } In the hypothetical that you want to check somewhere the user is not currently: class SwedenLocation implements Location { boolean isAdult(User u) { return u.age() >= 18; } boolean isOfDrinkinAge(User u) { return u.age() >= 18; } } var sweden = new SwedenLocation(); sweden.isOfDrinkingAge(user);
    • vips7L 2y ago
      On a side note, this discussion really made me realize how useful concise method bodies would be in Java: https://openjdk.org/jeps/8209434 https://openjdk.org/jeps/8209434
    • Terr_ 2y ago
      That feels like unnecessary levels of indirection to provide a method that shouldn't be on the User anyway. j = Jurisdiction.fromUserLocation(user); j.isOfDrinkingAge(user);
      • vips7L 2y ago
        > that shouldn't be on the User anyway. That’s just your opinion. It’s ok to provide convenience functions. I see no difference between the amount of indirection in our implementations, except mine is in the more natural place and you don’t have to know how to get a location or jurisdiction to answer the question: “is this user an adult?”. Knowing that it uses a location or jurisdiction is an implementation detail that you shouldn’t couple yourself to. Cheers mate, I think I’m done moving goal posts for this conversation :)
    • ahoka 2y ago
      Wow, thanks for proving that OOP was a mistake.
      • vips7L 2y ago
        I challenge you to do it better then. Also from the guidelines: > Please don't post shallow dismissals, especially of other people's work. A good critical comment teaches us something.