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jkscm | 10 years ago

Using get() is just bad style and so is returning null where you could return Collections.emptyList().

Previous discussion on reddit: https://www.reddit.com/r/programming/comments/3pl7o0/java_8s...

tl;dr: use map, orElseGet, orElse

discuss

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nrinaudo|10 years ago

I feel get is acceptable style if you actually want to fail when there is no data to be had.

If you don't have a default value to provide, nor an alternate code path other than "sod this, I'm bailing", get is ok. Not quite as good as using a more specific exception through orElseGet, but not bad, exactly.

Also, if you have just called isPresent (and assume your data to be immutable), then get is ok - the alternative being to manually throw something like new IllegalStateException("the impossible has happened!"), which is not that much more useful, and is a pain to have to write all the time when you know it will not get called.

krisdol|10 years ago

>Using get() is just bad style and so is returning null where you could return Collections.emptyList().

I agree that you should never return null, but if get() is bad style I think you should send out that memo because I haven't yet seen codebases that agreed.

vbezhenar|10 years ago

Why it's bad? If I'm sure that this optional contains value, I don't see why it's bad. May be I checked this value presence few lines above.

serpix|10 years ago

If you are certain optional has a value, don't use optional.

Checking presence of value of an optional is an anti-pattern, the same as doing != null checks.

You should treat Optional the same as a List type with size 1. You never check if a list is size 1 before doing map or filter.