Comment by hdpe

2 days ago

Great list, even if I disagree with many of the ratings!

But astonished that Optional isn't mentioned either there or in the comments. A second way to represent no-value, with unclear and holy-war-ushering guidance on when to use, and the not exactly terse syntax I see everywhere:

Optional<Ick> ickOpt = Optional.ofNullable(ickGiver.newIck()); ickOpt.flatMap(IckWtfer::wtf).ifPresentOrElse((Wtf wtf) -> unreadable(wtf)), () -> { log.warn("in what universe is this clearer than a simple if == null statement?!"); });

2 comments

hdpe

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skribanto  2 days ago

Well, it can make some chained function composition easier.

  Ick1 result1 = potentiallyNull1();
  Ick2 result2 = (result1 == null) ? null : potentiallyNull2(result1);
  Ick3 result3 = (result2 == null) ? null : potentiallyNull3(result2);

vs

  Ick3 result3 = potentiallyNone1()
    .flatMap(potentiallyNone2)
    .flatMap(potentiallyNone3);

You could maybe move the null check inside the method in the former and it cleans it up a bit, but in the latter you can have methods that are explicitly marked as taking NonNull in their type signature which is nice.

munksbeer  1 day ago

I don't grumble about Java much, I make my living with it and enjoy it. But Optional is a bane.

We use NullAway and I just never use Optional unless it really, really makes sense.